Android 8.1 相容性定義

一、簡介

本文檔列舉了裝置與 Android 8.1 相容必須滿足的要求。

「MUST」、「MUST NOT」、「REQUIRED」、「SHALL」、「SHALL NOT」、「SHOULD」、「SHOULD NOT」、「RECOMMENDED」、「MAY」和「OPTIONAL」的使用符合 IETF 標準RFC2119中定義的標準。

在本文檔中,「裝置實現者」或「實施者」是指開發運行 Android 8.1 的硬體/軟體解決方案的個人或組織。 “設備實現”或“實現是這樣開發的硬體/軟體解決方案。

若要被視為與 Android 8.1 相容,裝置實作必須滿足此相容性定義中提出的要求,包括透過引用納入的任何文件。

如果第 10 節中所述的此定義或軟體測試是沉默的、不明確的或不完整的,則設備實現者有責任確保與現有實現的兼容性。

因此, Android 開源專案既是 Android 的參考實現,也是首選實現。強烈建議設備實現者最大程度地基於 Android 開源專案提供的「上游」原始程式碼來實現其實現。雖然假設某些組件可以替換為替代實現,但強烈建議不要遵循這種做法,因為通過軟體測試將變得更加困難。實作者有責任確保與標準 Android 實作完全行為相容,包括相容性測試套件。最後,請注意,本文檔明確禁止某些組件替換和修改。

本文檔中連結的許多資源直接或間接源自 Android SDK,並且在功能上與該 SDK 文件中的資訊相同。在任何情況下,如果本相容性定義或相容性測試套件與 SDK 文件不一致,則 SDK 文件被視為具有權威性。本文檔中連結資源中提供的任何技術細節均被視為本相容性定義的一部分。

1.1 文檔結構

1.1.1.設備類型的要求

第 2 部分包含適用於特定設備類型的所有必須和強烈建議的要求。第 2 節的每個小節專用於特定的設備類型。

第 2 節之後的部分列出了所有普遍適用於任何 Android 裝置實現的其他要求。這些要求在本文檔中被稱為「核心要求」。

1.1.2.需求ID

需求 ID 是為 MUST 需求分配的。

  • 僅針對必須要求分配 ID。
  • 強烈建議的要求標記為 [SR],但未分配 ID。
  • ID 包括:設備類型 ID - 條件 ID - 要求 ID(例如 C-0-1)。

每個ID的定義如下:

  • 設備類型 ID(更多資訊請參閱2. 設備類型
    • C:核心(適用於任何 Android 裝置實現的要求)
    • H:Android手持設備
    • T:Android 電視設備
    • 答:Android 汽車實施
  • 條件ID
    • 當要求是無條件時,該ID設定為0。
    • 當要求是有條件的時,為第一個條件分配1,並且在相同部分和相同設備類型內數字加1。
  • 需求ID
    • ID從1開始,在相同的部分和相同的條件下加1。

2. 設備類型

雖然 Android 開源專案提供了可用於各種裝置類型和外形規格的軟體堆疊,但也有少數裝置類型擁有相對完善的應用程式分發生態系統。

本節介紹這些設備類型以及適用於每種設備類型的附加要求和建議。

所有不適合任何所描述的裝置類型的 Android 裝置實作仍然必須滿足本相容性定義其他部分中的所有要求。

2.1 設備配置

有關不同設備類型的硬體配置的主要差異,請參閱本節中隨後的特定於設備的要求。

2.2.手持設備要求

Android 手持裝置是指通常手持使用的 Android 裝置實現,例如 MP3 播放器、手機或平板電腦。

如果 Android 裝置實現滿足以下所有條件,則將其歸類為手持裝置:

  • 擁有提供行動性的電源,例如電池。
  • 螢幕物理對角線尺寸在 2.5 至 8 吋範圍內。

本節其餘部分的附加要求特定於 Android 手持裝置實作。

注意:不適用於 Android 平板電腦裝置的要求標示 *。

2.2.1.硬體

螢幕尺寸(第 7.1.1.1 節)

手持設備實現:

  • [H-0-1] 螢幕的實體對角線尺寸必須至少為 2.5 吋。 *

螢幕密度(第 7.1.1.3 節)

手持設備實現:

  • [H-SR] 強烈建議為使用者提供更改顯示尺寸的能力。

舊版應用程式相容模式(第 7.1.5 節)

手持設備實現:

  • [H-0-1] 必須支援由上游 Android 開源程式碼實現的舊版應用程式相容模式。也就是說,設備實作不得更改啟動相容模式的觸發器或閾值,且不得更改相容模式本身的行為。

鍵盤(第 7.2.1 節)

手持設備實現:

  • [H-0-1] 必須支援第三方輸入法編輯器 (IME) 應用程式。

導航鍵(第 7.2.3 節)

手持設備實現:

  • [H-0-1] 必須提供主頁、最近存取和返回功能。

  • [H-0-2] 必須將後退功能 ( KEYCODE_BACK ) 的正常按下事件和長按事件傳送至前台應用程式。

觸控螢幕輸入(第 7.2.4 節)

手持設備實現:

  • [H-0-1] 必須支援觸控螢幕輸入。

加速度計(第 7.3.1 節)

手持設備實現:

  • [H-SR] 強烈建議包含 3 軸加速度計。

如果手持設備實現包括 3 軸加速計,則:

  • [H-1-1] 必須能夠以至少 100 Hz 的頻率報告事件。

陀螺儀(第 7.3.4 節)

如果手持設備實作包括陀螺儀,它們:

  • [H-1-1] 必須能夠以至少 100 Hz 的頻率報告事件。

接近感測器(第 7.3.8 節)

可進行語音通話並在getPhoneType中指示除PHONE_TYPE_NONE以外的任何值的手持裝置實現:

  • 應包括接近感測器。

姿態感知器(第 7.3.12 節)

手持設備實現:

  • 建議支援 6 自由度的姿態感測器。

藍牙(第 7.4.3 節)

手持設備實現:

  • 應包括對藍牙和藍牙 LE 的支援。

資料保護程序(第 7.4.7 節)

如果手持設備實施包括按流量計費的連接,則:

  • [H-1-1] 必須提供資料保護模式。

最小內存和存儲(第 7.6.1 節)

如果手持裝置實作聲明僅支援 32 位元 ABI:

  • [H-1-1] 如果預設顯示器使用高達 qHD 的幀緩衝區解析度(例如 FWVGA),則核心和使用者空間可用的記憶體必須至少為 416MB。

  • [H-2-1] 如果預設顯示器使用高達 HD+ 的幀緩衝區解析度(例如 HD、WSVGA),則核心和使用者空間可用的記憶體必須至少為 592MB。

  • [H-3-1] 如果預設顯示器使用高達 FHD 的幀緩衝區解析度(例如 WSXGA+),則核心和使用者空間可用的記憶體必須至少為 896MB。

  • [H-4-1] 如果預設顯示器使用高達 QHD(例如 QWXGA)的幀緩衝區分辨率,則內核和用戶空間可用的記憶體必須至少為 1344MB。

如果手持裝置實作聲明支援 32 位元和 64 位元 ABI:

  • [H-5-1] 如果預設顯示器使用高達 qHD 的幀緩衝區解析度(例如 FWVGA),則核心和使用者空間可用的記憶體必須至少為 816MB。

  • [H-6-1] 如果預設顯示器使用高達 HD+ 的幀緩衝區解析度(例如 HD、WSVGA),則核心和使用者空間可用的記憶體必須至少為 944MB。

  • [H-7-1] 如果預設顯示器使用高達 FHD 的幀緩衝區解析度(例如 WSXGA+),則核心和使用者空間可用的記憶體必須至少為 1280MB。

  • [H-8-1] 如果預設顯示器使用高達 QHD(例如 QWXGA)的幀緩衝區分辨率,則內核和用戶空間可用的記憶體必須至少為 1824MB。

請注意,上面的「核心和用戶空間可用的記憶體」是指除了已經專用於硬體組件(例如無線電、視訊等)的任何記憶體之外提供的記憶體空間,這些硬體元件在裝置實作上不受核心控制。

如果手持裝置實作包含小於或等於 1GB 可供核心和使用者空間使用的內存,則:

  • [H-9-1] 必須聲明功能標誌android.hardware.ram.low
  • [H-9-2] 必須具有至少 1.1 GB 的非揮發性儲存空間來儲存應用程式私有資料(也稱為「/data」分割區)。

如果手持裝置實作包括可供核心和使用者空間使用的超過 1GB 的內存,則:

  • [H-10-1] 必須有至少 4GB 的非揮發性儲存可用於應用程式私有資料(也稱為「/data」分割區)。
  • 應聲明功能標誌android.hardware.ram.normal

應用程式共用儲存(第 7.6.2 節)

手持設備實現:

  • [H-0-1] 不得提供小於 1 GiB 的應用程式共用儲存。

USB 週邊模式(第 7.7.1 節)

手持設備實現:

  • 應包括一個支援週邊模式的 USB 連接埠。

如果手持設備實作包括支援週邊模式的 USB 端口,則:

  • [H-1-1] 必須實作 Android 開放附件 (AOA) API。 *

麥克風(第 7.8.1 節)

手持設備實現:

  • [H-0-1] 必須包含麥克風。

音訊輸出(第 7.8.2 節)

手持設備實現:

  • [H-0-1] 必須有音訊輸出並聲明android.hardware.audio.output

虛擬實境模式(第 7.9.1 節)

如果手持設備實現包括對 VR 模式的支持,則它們:

  • [H-1-1] 必須聲明android.software.vr.mode功能。 *

如果裝置實作聲明android.software.vr.mode功能,則:

  • [H-2-1] 必須包含一個實作android.service.vr.VrListenerService應用程序,VR 應用程式可以透過android.app.Activity#setVrModeEnabled啟用該服務。 *

虛擬實境高效能(第 7.9.2 節)

如果手持裝置實現能夠滿足聲明android.hardware.vr.high_performance功能標誌的所有要求,則:

  • [H-1-1] 必須聲明android.hardware.vr.high_performance功能標誌。 *

2.2.2.多媒體

音訊編碼(第 5.1.1 節)

手持設備實作必須支援以下音訊編碼:

  • [H-0-1] AMR-NB
  • [H-0-2] AMR-WB
  • [H-0-3] MPEG-4 AAC 設定檔 (AAC LC)
  • [H-0-4] MPEG-4 HE AAC 設定檔 (AAC+)
  • [H-0-5] AAC ELD(增強型低延遲AAC)

音訊解碼(第 5.1.2 節)

手持設備實作必須支援以下音訊解碼:

  • [H-0-1] AMR-NB
  • [H-0-2] AMR-WB

視訊編碼(第 5.2 節)

手持設備實作必須支援以下視訊編碼並使其可供第三方應用程式使用:

  • [H-0-1] H.264 AVC
  • [H-0-2] VP8

視訊解碼(第 5.3 節)

手持設備實作必須支援以下視訊解碼:

  • [H-0-1] H.264 AVC。
  • [H-0-2] H.265 HEVC。
  • [H-0-3] MPEG-4 SP。
  • [H-0-4] VP8。
  • [H-0-5] VP9。

2.2.3.軟體

WebView 相容性(第 3.4.1 節)

手持設備實現:

  • [H-0-1] 必須提供android.webkit.Webview API 的完整實作。

瀏覽器相容性(第 3.4.2 節)

手持設備實現:

  • [H-0-1] 必須包含用於一般使用者 Web 瀏覽的獨立瀏覽器應用程式。

啟動器(第 3.8.1 節)

手持設備實現:

  • [H-SR] 強烈建議實作支援應用程式內固定快捷方式和小部件的預設啟動器。

  • [H-SR] 強烈建議實作預設啟動器,以便透過ShortcutManager API 快速存取第三方應用程式提供的其他捷徑。

  • [H-SR] 強烈建議包含一個顯示應用程式圖示徽章的預設啟動器應用程式。

小部件(第 3.8.2 節)

手持設備實現:

  • [H-SR] 強烈建議支援第三方應用程式小工具。

通知(第 3.8.3 節)

手持設備實現:

  • [H-0-1] 必須允許第三方應用透過NotificationNotificationManager API 類別向使用者通知值得注意的事件。
  • [H-0-2] 必須支援豐富的通知。
  • [H-0-3] 必須支援平視通知。
  • [H-0-4] 必須包含通知欄,使用戶能夠透過使用者功能(例如 AOSP 中實現的操作按鈕或控制面板)直接控制(例如回覆、暫停、關閉、封鎖)通知。

搜尋(第 3.8.4 節)

手持設備實現:

  • [H-SR] 強烈建議在設備上實現助手來處理輔助操作

鎖定螢幕媒體控制(第 3.8.10 節)

如果 Android 手持裝置實現支援鎖定螢幕,則:

  • [H-1-1] 必須顯示鎖定畫面通知,包括媒體通知範本。

設備管理(第 3.9 節)

如果手持裝置實現支援安全鎖定螢幕,則它們:

  • [H-1-1] 必須實施 Android SDK 文件中定義的全部裝置管理策略。

輔助功能(第 3.10 節)

手持設備實現:

  • [H-SR] 必須支援第三方無障礙服務。

  • [H-SR] 強烈建議在裝置上預先載入與TalkBack 開源專案中提供的 Switch Access 和 TalkBack(針對預先載入的文字轉語音引擎支援的語言)無障礙服務功能相當或超過的無障礙服務。

文字轉語音(第 3.11 節)

手持設備實現:

  • [H-0-1] 必須支援安裝第三方 TTS 引擎。

  • [H-SR] 強烈建議包含支援裝置上可用語言的 TTS 引擎。

快速設定(第 3.13 節)

手持設備實現:

  • [H-SR] 強烈建議包含快速設定 UI 元件。

配套設備配對(第 3.15 節)

如果 Android 手持裝置實現聲明FEATURE_BLUETOOTHFEATURE_WIFI支持,則:

  • [H-1-1] 必須支援配套設備配對功能。

2.2.4.性能和功率

使用者體驗一致性(第 8.1 節)

對於手持設備實現:

  • [H-0-1]一致的幀延遲。不一致的幀延遲或渲染幀延遲的發生頻率不得超過每秒 5 幀,且應低於每秒 1 幀。
  • [H-0-2]使用者介面延遲。裝置實作必須透過在 36 秒內捲動 Android 相容性測試套件 (CTS) 定義的 10K 清單條目清單來確保低延遲使用者體驗。
  • [H-0-3]任務切換。當多個應用程式已啟動時,啟動後重新啟動已執行的應用程式所用時間必須少於 1 秒。

文件 I/O 存取效能(第 8.2 節)

手持設備實現:

  • [H-0-1] 必須確保至少 5 MB/s 的順序寫入效能。
  • [H-0-2] 必須確保至少 0.5 MB/s 的隨機寫入效能。
  • [H-0-3] 必須確保至少 15 MB/s 的順序讀取效能。
  • [H-0-4] 必須確保至少 3.5 MB/s 的隨機讀取效能。

省電模式(第 8.3 節)

對於手持設備實現:

  • [H-0-1] 所有免於應用程式待機和打盹節能模式的應用程式必須對最終用戶可見。
  • [H-0-2] App Standby 和 Doze 省電模式的觸發、維護、喚醒演算法以及全域系統設定的使用不得偏離 Android 開源專案。

功耗會計(第 8.4 節)

手持設備實現:

  • [H-0-1] 必須提供每個組件的電源配置文件,該配置文件定義每個硬體組件的電流消耗值以及組件隨時間推移造成的大致電池消耗(如 Android 開源專案網站中所述)。
  • [H-0-2] 必須以毫安培小時 (mAh) 為單位報告所有功耗值。
  • [H-0-3] 必須報告每個進程 UID 的 CPU 功耗。 Android開源專案透過uid_cputime核心模組實作來滿足要求。
  • [H-0-4] 必須透過adb shell dumpsys batterystats shell 指令向應用程式開發人員提供此電量使用情況。
  • 如果無法將硬體組件的電源使用歸因於應用程序,則應歸因於硬體組件本身。

如果手持裝置實作包括螢幕或視訊輸出,則它們:

2.2.5。安全模型

權限(第 9.1 節)

手持設備實現:

  • [H-0-1] 必須允許第三方應用透過android.permission.PACKAGE_USAGE_STATS權限存取使用情況統計信息,並提供用戶可訪問的機制來授予或撤銷對此類應用的訪問權限,以響應android.settings.ACTION_USAGE_ACCESS_SETTINGS意圖。

2.3.電視需求

An Android Television device refers to an Android device implementation that is an entertainment interface for consuming digital media, movies, games, apps, and/or live TV for users sitting about ten feet away (a “lean back” or “10-foot user介面").

如果 Android 裝置實現滿足以下所有條件,則將其歸類為電視:

  • 提供了一種機制來遠端控制可能距離使用者十英尺遠的顯示器上呈現的使用者介面。
  • 擁有對角線長度大於 24 吋的嵌入式螢幕顯示器或包含視訊輸出端口,例如 VGA、HDMI、DisplayPort 或用於顯示的無線端口。

本節其餘部分的附加要求特定於 Android Television 裝置實作。

2.3.1.硬體

非觸控式導航(第 7.2.2 節)

電視設備實現:

導航鍵(第 7.2.3 節)

電視設備實現:

  • [T-0-1] 必須提供主頁和返回功能。
  • [T-0-2] 必須將後退功能 ( KEYCODE_BACK ) 的正常按下事件和長按事件傳送至前台應用程式。

按鈕映射(第 7.2.6.1 節)

電視設備實現:

  • [T-0-1] 必須包含對遊戲控制器的支援並聲明android.hardware.gamepad功能標誌。

遠端控制(第 7.2.7 節)

電視設備實現:

陀螺儀(第 7.3.4 節)

如果電視設備實作包含陀螺儀,則它們:

  • [T-1-1] 必須能夠以至少 100 Hz 的頻率報告事件。

藍牙(第 7.4.3 節)

電視設備實現:

  • [T-0-1] 必須支援藍牙和藍牙 LE。

最小內存和存儲(第 7.6.1 節)

電視設備實現:

  • [T-0-1] 必須有至少 4GB 的非揮發性儲存可用於應用程式私有資料(也稱為「/data」分割區)
  • [T-0-2] 當核心和使用者空間可用記憶體少於 1GB 時,必須為ActivityManager.isLowRamDevice()傳回「true」。

麥克風(第 7.8.1 節)

電視設備實現:

  • 應包括麥克風。

音訊輸出(第 7.8.2 節)

電視設備實現:

  • [T-0-1] 必須有音訊輸出並聲明android.hardware.audio.output

2.3.2.多媒體

音訊編碼(第 5.1 節)

電視設備實作必須支援以下音訊編碼:

  • [T-0-1] MPEG-4 AAC 設定檔 (AAC LC)
  • [T-0-2] MPEG-4 HE AAC 設定檔 (AAC+)
  • [T-0-3] AAC ELD(增強型低延遲AAC)

視訊編碼(第 5.2 節)

電視設備實作必須支援以下視訊編碼:

  • [T-0-1] H.264 AVC
  • [T-0-2] VP8

H-264(第 5.2.2 節)

電視設備實現是:

  • [T-SR] 強烈建議支援 720p 和 1080p 解析度影片的 H.264 編碼。
  • [T-SR] 強烈建議支援每秒 30 幀 (fps) 的 1080p 解析度影片的 H.264 編碼。

視訊解碼(第 5.3 節)

電視設備實作必須支援以下視訊解碼:

  • [T-0-1] H.264 AVC
  • [T-0-2] H.265 HEVC
  • [T-0-3] MPEG-4 SP
  • [T-0-4] VP8
  • [T-0-5] VP9

強烈建議電視設備實現支援以下視訊解碼:

  • [T-SR] MPEG-2

H.264(第 5.3.4 節)

如果電視設備實現支援 H.264 解碼器,則它們:

  • [T-1-1] 必須支援 High Profile Level 4.2 和 HD 1080p(60 fps)解碼設定檔。
  • [T-1-2] 必須能夠使用下表所示的兩種 HD 設定檔進行解碼,並使用 Baseline Profile、Main Profile 或 High Profile Level 4.2 進行編碼

H.265 (HEVC)(第 5.3.5 節)

如果電視設備實現支援 H.265 編解碼器和 HD 1080p 解碼配置文件,則:

  • [T-1-1] 必須支援 Main Profile Level 4.1 主層。
  • [T-SR] 強烈建議支援 HD 1080p 的 60 fps 視訊幀率。

如果電視設備實現支援 H.265 編解碼器和 UHD 解碼配置文件,則:

  • [T-2-1] 編解碼器必須支援 Main10 5 級主層設定檔。

VP8(第 5.3.6 節)

如果電視設備實作支援 VP8 編解碼器,則它們:

  • [T-1-1] 必須支援 HD 1080p60 解碼設定檔。

如果電視設備實作支援 VP8 編解碼器並支援 720p,則:

  • [T-2-1] 必須支援 HD 720p60 解碼設定檔。

VP9(第 5.3.7 節)

如果電視設備實現支援 VP9 編解碼器和 UHD 視訊解碼,則:

  • [T-1-1] 必須支援 8 位元顏色深度,並且應該支援 VP9 設定檔 2(10 位元)。

如果電視設備實作支援 VP9 編解碼器、1080p 設定檔和 VP9 硬體解碼,則:

  • [T-2-1] 必須支援 1080p 的 60 fps。

安全媒體(第 5.8 節)

如果設備實現是 Android Television 設備並支援 4K 分辨率,則:

  • [T-1-1] 所有有線外部顯示器必須支援 HDCP 2.2。

如果電視設備實現不支援 4K 分辨率,則:

  • [T-2-1] 所有有線外部顯示器必須支援 HDCP 1.4。

電視設備實現:

  • [T-SR] 強烈建議支援安全流的同步解碼。至少,強烈建議同時解碼兩個串流。

音訊輸出音量(第 5.5.3 節)

電視設備實現:

  • [T-0-1] 必須支援系統主音量和受支援輸出上的數位音訊輸出音量衰減,壓縮音訊直通輸出(裝置上未進行音訊解碼)除外。

2.3.3.軟體

電視設備實現:

WebView 相容性(第 3.4.1 節)

電視設備實現:

  • [T-0-1] 必須提供android.webkit.Webview API 的完整實作。

鎖定螢幕媒體控制(第 3.8.10 節)

如果 Android Television 裝置實作支援鎖定螢幕,則:

  • [T-1-1] 必須顯示鎖定畫面通知,包括媒體通知範本。

多窗口(第 3.8.14 節)

電視設備實現:

  • [T-SR] 強烈建議支持畫中畫 (PIP) 模式多視窗。

輔助功能(第 3.10 節)

電視設備實現:

  • [T-SR] 必須支援第三方無障礙服務。

  • [T-SR] 強烈建議Android Television 裝置實現在裝置上預先載入可存取性服務,其功能相當於或超過Switch Access 和TalkBack(適用於預先載入的文字轉語音引擎支援的語言)可存取性服務的功能,如對講開源專案

文字轉語音(第 3.11 節)

如果裝置實作報告了 android.hardware.audio.output 功能,則:

  • [T-SR] 強烈建議包含支援裝置上可用語言的 TTS 引擎。

  • [T-0-1] 必須支援安裝第三方 TTS 引擎。

電視輸入框架(第 3.12 節)

電視設備實現:

  • [T-0-1] 必須支援 TV 輸入框架。

2.2.4.性能和功率

使用者體驗一致性(第 8.1 節)

對於電視設備實現:

  • [T-0-1]一致的幀延遲。不一致的幀延遲或渲染幀延遲的發生頻率不得超過每秒 5 幀,且應低於每秒 1 幀。

文件 I/O 存取效能(第 8.2 節)

電視設備實現:

  • [T-0-1] 必須確保至少 5MB/s 的順序寫入效能。
  • [T-0-2] 必須確保至少 0.5MB/s 的隨機寫入效能。
  • [T-0-3] 必須確保至少 15MB/s 的順序讀取效能。
  • [T-0-4] 必須確保至少 3.5MB/s 的隨機讀取效能。

省電模式(第 8.3 節)

對於電視設備實現:

  • [T-0-1] 所有免於應用程式待機和打盹節能模式的應用程式必須對最終用戶可見。
  • [T-0-2] App Standby 和 Doze 省電模式的觸發、維護、喚醒演算法以及全域系統設定的使用不得偏離 Android 開源專案。

功耗會計(第 8.4 節)

電視設備實現:

  • [T-0-1] 必須提供每個組件的電源配置文件,該配置文件定義每個硬體組件的電流消耗值以及組件隨時間推移造成的大致電池消耗(如 Android 開源專案網站中所述)。
  • [T-0-2] 必須以毫安培小時 (mAh) 為單位報告所有功耗值。
  • [T-0-3] 必須報告每個進程 UID 的 CPU 功耗。 Android開源專案透過uid_cputime核心模組實作來滿足要求。
  • 如果無法將硬體組件的電源使用歸因於應用程序,則應歸因於硬體組件本身。
  • [T-0-4] 必須透過adb shell dumpsys batterystats shell 指令向應用程式開發人員提供此電量使用情況。

2.4.手錶要求

Android Watch 裝置是指設計用於配戴在身體上(可能戴在手腕上)的 Android 裝置實現。

如果 Android 裝置實作符合以下所有條件,則被歸類為 Watch:

  • 螢幕的物理對角線長度在 1.1 到 2.5 吋之間。
  • 提供可佩戴在身上的機構。

本節其餘部分的附加要求特定於 Android Watch 裝置實作。

2.4.1.硬體

螢幕尺寸(第 7.1.1.1 節)

觀看設備實現:

  • [W-0-1] 螢幕的實體對角線尺寸必須在 1.1 到 2.5 吋範圍內。

導航鍵(第 7.2.3 節)

觀看設備實現:

  • [W-0-1] 必須具備可供使用者使用的 Home 功能和 Back 功能(處於UI_MODE_TYPE_WATCH時除外)。

觸控螢幕輸入(第 7.2.4 節)

觀看設備實現:

  • [W-0-2] 必須支援觸控螢幕輸入。

加速度計(第 7.3.1 節)

觀看設備實現:

  • [W-SR] 強烈建議包含 3 軸加速度計。

藍牙(第 7.4.3 節)

觀看設備實現:

  • [W-0-1] 必須支援藍牙。

最小內存和存儲(第 7.6.1 節)

觀看設備實現:

  • [W-0-1] 必須有至少 1GB 的非揮發性儲存可用於應用程式私有資料(也稱為「/data」分割區)
  • [W-0-2] 必須至少有 416MB 記憶體可供核心和使用者空間使用。

麥克風(第 7.8.1 節)

觀看設備實現:

  • [W-0-1] 必須包含麥克風。

音訊輸出(第 7.8.1 節)

觀看設備實現:

  • 可以但不應該有音訊輸出。

2.4.2.多媒體

無額外要求。

2.4.3.軟體

觀看設備實現:

  • [W-0-1] 必須聲明 android.hardware.type.watch 功能。
  • [W-0-2] 必須支援 uiMode = UI_MODE_TYPE_WATCH

搜尋(第 3.8.4 節)

觀看設備實現:

  • [W-SR] 強烈建議在設備上實現助手來處理輔助操作

輔助功能(第 3.10 節)

觀看聲明android.hardware.audio.output功能標誌的裝置實作:

  • [W-1-1] 必須支援第三方無障礙服務。

  • [W-SR] 強烈建議在裝置上預先載入與Talkback 開源專案中提供的 Switch Access 和 TalkBack(針對預先載入的文字轉語音引擎支援的語言)無障礙服務功能相當或超過的無障礙服務。

文字轉語音(第 3.11 節)

如果 Watch 裝置實作報告了 android.hardware.audio.output 功能,則:

  • [W-SR] 強烈建議包含支援裝置上可用語言的 TTS 引擎。

  • [W-0-1] 必須支援安裝第三方 TTS 引擎。

2.5.汽車要求

Android Automotive 實作是指運行 Android 作為部分或全部系統和/或資訊娛樂功能的作業系統的車輛主機。

如果 Android 裝置實作聲明了android.hardware.type.automotive功能或滿足以下所有條件,則它們被歸類為汽車。

  • 作為汽車的一部分嵌入或可插入汽車。
  • 使用駕駛座排中的畫面作為主顯示幕。

本節其餘部分的附加要求是特定於 Android Automotive 裝置實作。

2.5.1.硬體

螢幕尺寸(第 7.1.1.1 節)

汽車設備實現:

  • [A-0-1] 螢幕的實體對角線尺寸必須至少為 6 吋。
  • [A-0-2] 螢幕尺寸佈局必須至少為 750 dp x 480 dp。

導航鍵(第 7.2.3 節)

汽車設備實現:

  • [A-0-1] 必須提供「首頁」功能,並且可以提供「返回」和「最近」功能。
  • [A-0-2] 必須將後退功能 ( KEYCODE_BACK ) 的正常按下事件和長按事件傳送至前台應用程式。

加速度計(第 7.3.1 節)

汽車設備實現:

  • [A-SR] 強烈建議包含 3 軸加速度計。

如果汽車設備實現包括 3 軸加速度計,則:

GPS(第 7.3.3 節)

如果汽車設備實作包括 GPS/GNSS 接收器並透過android.hardware.location.gps功能標誌向應用程式報告該功能:

  • [A-1-1] GNSS 技術世代必須是「2017 年」或更新的年份。

陀螺儀(第 7.3.4 節)

如果汽車設備實作包括陀螺儀,則它們:

  • [A-1-1] 必須能夠以至少 100 Hz 的頻率報告事件。

Android 汽車專用感知器(第 7.3.11 節)目前檔位(第 7.3.11.1 節)

汽車設備實現:

  • 應提供當前齒輪作為SENSOR_TYPE_GEAR

日夜模式(第 7.3.11.2 節)

汽車設備實現:

  • [A-0-1] 必須支援定義為SENSOR_TYPE_NIGHT日間/夜間模式。
  • [A-0-2] SENSOR_TYPE_NIGHT標誌的值必須與儀表板日/夜模式一致,並且應基於環境光感測器輸入。
  • 底層環境光感測器可能與光度計相同。

駕駛狀態(第 7.3.11.3 節)

汽車設備實現:

  • [A-0-1] 必須支援定義為SENSOR_TYPE_DRIVING_STATUS駕駛狀態,當車輛完全停止並停放時,預設值為DRIVE_STATUS_UNRESTRICTED 。設備製造商有責任根據適用於產品出貨市場的所有法律和法規來配置SENSOR_TYPE_DRIVING_STATUS

輪速(第 7.3.11.4 節)

汽車設備實現:

  • [A-0-1] 必須提供定義為SENSOR_TYPE_CAR_SPEED車輛速度。

藍牙(第 7.4.3 節)

汽車設備實現:

  • [A-0-1] 必須支援藍牙並且應該支援藍牙 LE。

  • [A-0-2] Android Automotive 實作必須支援以下藍牙設定檔:

    • 透過免持模式 (HFP) 撥打電話。
    • 透過音訊分發設定檔 (A2DP) 進行媒體播放。
    • 透過遠端控製設定檔 (AVRCP) 進行媒體播放控制。
    • 使用電話簿存取設定檔 (PBAP) 共用聯絡人。
  • 應支援訊息存取設定檔(MAP)。

最低網路能力(第 7.4.5 節)

汽車設備實現:

  • 應包括對基於蜂窩網路的數據連接的支援。

最小內存和存儲(第 7.6.1 節)

汽車設備實現:

  • [A-0-1] 必須有至少 4GB 的非揮發性儲存可用於應用程式私有資料(也稱為「/data」分割區)

USB 週邊模式(第 7.7.1 節)

汽車設備實現:

  • 應包括一個支援週邊模式的 USB 連接埠。

麥克風(第 7.8.1 節)

汽車設備實現:

  • [A-0-1] 必須包含麥克風。

音訊輸出(第 7.8.2 節)

汽車設備實現:

  • [A-0-1] 必須有音訊輸出並聲明android.hardware.audio.output

2.5.2.多媒體

音訊編碼(第 5.1 節)

汽車設備實作必須支援以下音訊編碼:

  • [A-1-1] MPEG-4 AAC 設定檔 (AAC LC)
  • [A-1-2] MPEG-4 HE AAC 設定檔 (AAC+)
  • [A-1-3] AAC ELD(增強型低延遲 AAC)

視訊編碼(第 5.2 節)

汽車設備實作必須支援以下視訊編碼:

  • [A-0-1] H.264 AVC
  • [A-0-2] VP8

視訊解碼(第 5.3 節)

汽車設備實作必須支援以下視訊解碼:

  • [A-0-1] H.264 AVC
  • [A-0-2] MPEG-4 SP
  • [A-0-3] VP8
  • [A-0-4] VP9

強烈建議汽車設備實現支援以下視訊解碼:

  • [A-SR] H.265 HEVC

2.5.3.軟體

汽車設備實現:

  • [A-0-1] 必須聲明 android.hardware.type.automotive 功能。
  • [A-0-2] 必須支援 uiMode = UI_MODE_TYPE_CAR
  • [A-0-3] Android Automotive 實作必須支援android.car.*命名空間中的所有公用 API。

WebView 相容性(第 3.4.1 節)

汽車設備實現:

  • [A-0-1] 必須提供android.webkit.Webview API的完整實作。

通知(第 3.8.3 節)

Android 汽車裝置實現:

搜尋(第 3.8.4 節)

汽車設備實現:

  • [A-0-1] 必須在設備上實現助手來處理輔助操作

媒體 UI(第 3.14 節)

汽車設備實現:

  • [A-0-1] 必須包含一個 UI 框架,以支援使用媒體 API 的第三方應用,如第 3.14 節所述。

2.2.4.性能和功率

省電模式(第 8.3 節)

對於汽車設備實施:

  • [A-0-1] 所有免於應用程式待機和打盹節能模式的應用程式必須對最終用戶可見。
  • [A-0-2] App Standby 和 Doze 省電模式的觸發、維護、喚醒演算法以及全域系統設定的使用不得偏離 Android 開源專案。

功耗會計(第 8.4 節)

汽車設備實現:

  • [A-0-1] 必須提供每個組件的電源配置文件,該配置文件定義每個硬體組件的電流消耗值以及組件隨時間推移造成的大致電池消耗量(如Android 開源專案網站中所述) 。
  • [A-0-2] 必須以毫安培小時 (mAh) 為單位報告所有功耗值。
  • [A-0-3] 必須報告每個進程 UID 的 CPU 功耗。 Android開源專案透過uid_cputime核心模組實作來滿足要求。
  • 如果無法將硬體組件的電源使用歸因於應用程序,則應歸因於硬體組件本身。
  • [A-0-4] 必須透過adb shell dumpsys batterystats shell 指令向應用程式開發者提供此電量使用情況。

2.2.5。安全模型

多用戶支援(第 9.5 節)

如果汽車設備實施包括多個用戶,他們:

  • [A-1-1] 必須包含一個訪客帳戶,該帳戶允許車輛系統提供所有功能,而無需使用者登入。

汽車系統隔離(第 9.14 節)

汽車設備實現:

  • [A-0-1] 必須把關來自 Android 框架車輛子系統的訊息,例如,將允許的訊息類型和訊息源列入白名單。
  • [A-0-2] 必須監視來自 Android 框架或第三方應用程式的拒絕服務攻擊。這可以防止惡意軟體充斥車輛網絡,從而導致車輛子系統故障。

2.6。平板電腦要求

Android 平板電腦裝置是指通常透過雙手握持而不是翻蓋形式使用的 Android 裝置來實現。

如果 Android 裝置實現滿足以下所有條件,則將其歸類為平板電腦:

  • 擁有提供行動性的電源,例如電池。
  • 螢幕物理對角線尺寸在 7 至 18 吋範圍內。

平板電腦設備實現與手持設備實現具有類似的要求。例外情況在該部分中以 和 * 表示,並在本部分中註明以供參考。

2.4.1.硬體

螢幕尺寸(第 7.1.1.1 節)

平板電腦設備實現:

  • [Ta-0-1] 螢幕尺寸必須在 7 到 18 吋之間。

最小內存和存儲(第 7.6.1 節)

手持裝置要求中所列的小/普通螢幕的螢幕密度不適用於平板電腦。

USB 週邊模式(第 7.7.1 節)

如果手持設備實作包括支援週邊模式的 USB 端口,則:

  • 可以實作 Android 開放附件 (AOA) API。

虛擬實境模式(第 7.9.1 節)

虛擬實境高效能(第 7.9.2 節)

虛擬實境要求不適用於平板電腦。

3、軟體

3.1.託管 API 相容性

託管的 Dalvik 字節碼執行環境是 Android 應用程式的主要工具。 Android 應用程式介面 (API) 是向在託管執行時間環境中運行的應用程式公開的一組 Android 平台介面。

  • [C-0-1] 裝置實作必須提供Android SDK公開的任何記錄的 API 或上游 Android 原始碼中用「@SystemApi」標記修飾的任何 API 的完整實現,包括所有記錄的行為。

  • [C-0-2] 裝置實作必須支援/保留 TestApi 註解 (@TestApi) 標記的所有類別、方法和關聯元素。

  • [C-0-3] 裝置實作不得省略任何託管 API、更改 API 介面或簽章、偏離記錄的行為或包含無操作,除非本相容性定義明確允許。

  • [C-0-4] 裝置實作必須仍然保持 API 存在並以合理的方式運行,即使 Android 包含的 API 的某些硬體功能被省略也是如此。有關此場景的具體要求,請參閱第 7 節

3.1.1.安卓擴充

Android 支援擴充託管 API,同時保持相同的 API 等級版本。

  • [C-0-1] Android 裝置實作必須預先載入共用程式庫ExtShared和服務ExtServices的 AOSP 實現,且版本高於或等於每個 API 等級允許的最低版本。例如,執行 API 等級 24 的 Android 7.0 裝置實作必須至少包含版本 1。

3.2.軟 API 相容性

除了第 3.1 節中的託管 API 之外,Android 還包括一個重要的僅運行時「軟」API,其形式為意圖、權限和 Android 應用程式的類似方面,這些方面無法在應用程式編譯時強制執行。

3.2.1.權限

  • [C-0-1] 設備實現者必須支援並強制執行權限參考頁中記錄的所有權限常數。請注意,第 9 節列出了與 Android 安全模型相關的其他要求。

3.2.2.建構參數

Android API 在android.os.Build 類別中包含許多常數,用於描述目前裝置。

  • [C-0-1] 為了跨裝置實作提供一致、有意義的值,下表包含對裝置實作必須遵守的這些值的格式的附加限制。
範圍細節
版本.發布目前執行的 Android 系統的版本,採用人類可讀的格式。此欄位必須具有8.1中定義的字串值之一。
版本.SDK目前執行的 Android 系統的版本,採用第三方應用程式程式碼可存取的格式。對於 Android 8.1,此欄位必須具有整數值 8.1_INT。
版本.SDK_INT目前執行的 Android 系統的版本,採用第三方應用程式程式碼可存取的格式。對於 Android 8.1,此欄位必須具有整數值 8.1_INT。
版本.增量裝置實現者選擇的值,以人類可讀的格式指定目前正在執行的 Android 系統的特定版本。該值不得重複用於提供給最終用戶的不同建置。此欄位的典型用途是指示使用哪個版本號或原始碼控制變更標識符來產生版本。該欄位的具體格式沒有要求,但不能為 null 或空字串 ("")。
木板設備實現者選擇的值,以人類可讀的格式標識設備使用的特定內部硬體。此欄位的一個可能用途是指示為設備供電的板的特定版本。此欄位的值必須可編碼為 7 位元 ASCII 並符合正規表示式「^[a-zA-Z0-9_-]+$」。
品牌反映最終用戶所知的與設備相關的品牌名稱的值。必須採用人類可讀的格式,並且應該代表設備的製造商或設備銷售的公司品牌。此欄位的值必須可編碼為 7 位元 ASCII 並符合正規表示式「^[a-zA-Z0-9_-]+$」。
支援_ABIS本機程式碼的指令集名稱(CPU 類型 + ABI 約定)。請參閱第 3.3 節。本機 API 相容性
SUPPORTED_32_BIT_ABIS本機程式碼的指令集名稱(CPU 類型 + ABI 約定)。請參閱第 3.3 節。本機 API 相容性
SUPPORTED_64_BIT_ABIS本機程式碼的第二指令集(CPU 類型 + ABI 約定)的名稱。請參閱第 3.3 節。本機 API 相容性
CPU_ABI本機程式碼的指令集名稱(CPU 類型 + ABI 約定)。請參閱第 3.3 節。本機 API 相容性
CPU_ABI2本機程式碼的第二指令集(CPU 類型 + ABI 約定)的名稱。請參閱第 3.3 節。本機 API 相容性
裝置設備實現者選擇的值,包含標識硬體功能配置和設備工業設計的開發名稱或代號。此欄位的值必須可編碼為 7 位元 ASCII 並符合正規表示式「^[a-zA-Z0-9_-]+$」。該設備名稱在產品的生命週期內不得更改。
指紋唯一標識此建置的字串。它應該是合理的人類可讀的。它必須遵循以下模板:

$(品牌)/$(產品)/
$(設備):$(版本.發佈)/$(ID)/$(版本.增量):$(類型)/$(標籤)

例如:

acme/我的產品/
mydevice:8.1/LMYXX/3359:userdebug/test-keys

指紋不得包含空白字元。如果上述模板中包含的其他字段具有空白字符,則必須在構建指紋中將它們替換為另一個字符,例如下劃線(“_”)字符。此欄位的值必須可編碼為 7 位元 ASCII。

硬體硬體的名稱(來自核心命令列或/proc)。它應該是合理的人類可讀的。此欄位的值必須可編碼為 7 位元 ASCII 並符合正規表示式「^[a-zA-Z0-9_-]+$」。
主持人一個字串,以人類可讀的格式唯一標識建構建構的主機。該欄位的具體格式沒有要求,但不能為 null 或空字串 ("")。
ID設備實現者選擇的標識符,用於引用特定版本,採用人類可讀的格式。該欄位可以與 android.os.Build.VERSION.INCRMENTAL 相同,但應該是一個對於最終用戶區分軟體版本足夠有意義的值。此欄位的值必須可編碼為 7 位元 ASCII 並符合正規表示式「^[a-zA-Z0-9._-]+$」。
製造商產品原始設備製造商 (OEM) 的商品名稱。該欄位的具體格式沒有要求,但不能為 null 或空字串 ("")。此欄位在產品的生命週期內不得更改。
模型設備實現者選擇的值,包含最終使用者已知的設備名稱。此名稱應與設備行銷和銷售給最終用戶時使用的名稱相同。該欄位的具體格式沒有要求,但不能為 null 或空字串 ("")。此欄位在產品的生命週期內不得更改。
產品設備實施者選擇的值,包含特定產品 (SKU) 的開發名稱或程式碼名稱,該產品在同一品牌中必須是唯一的。必須是人類可讀的,但不一定供最終用戶查看。此欄位的值必須可編碼為 7 位元 ASCII 並符合正規表示式「^[a-zA-Z0-9_-]+$」。該產品名稱在產品的生命週期內不得更改。
串口硬體序號,在具有相同型號和製造商的設備之間必須可用且唯一。此欄位的值必須可編碼為 7 位元 ASCII 並符合正規表示式「^([a-zA-Z0-9]{6,20})$」。
標籤由設備實現者選擇的以逗號分隔的標籤列表,可進一步區分建置。此欄位必須具有與三種典型 Android 平台簽章配置相對應的值之一:release-keys、dev-keys、test-keys。
時間表示建構發生時間的時間戳記的值。
類型由設備實現者選擇的值,指定建置的運行時配置。此欄位必須具有與三種典型 Android 運行時配置相對應的值之一:user、userdebug 或 eng。
使用者產生建置的使用者(或自動使用者)的名稱或使用者 ID。該欄位的具體格式沒有要求,但不能為 null 或空字串 ("")。
安全補丁指示建置的安全性修補程式等級的值。它必須表明該構建不會以任何方式受到指定 Android 公共安全公告中描述的任何問題的影響。它必須採用 [YYYY-MM-DD] 格式,與Android 公共安全公告Android 安全通報中記錄的定義字串相符,例如「2015-11-01」。
基本作業系統表示建置的 FINGERPRINT 參數的值,除 Android 公共安全公告中提供的補丁外,該值與此建置相同。它必須報告正確的值,如果這樣的建置不存在,則報告空字串(“”)。
引導程式裝置實現者選擇的值,以人類可讀的格式標識裝置中使用的特定內部引導程式版本。此欄位的值必須可編碼為 7 位元 ASCII 並符合正規表示式「^[a-zA-Z0-9._-]+$」。
取得無線電版本()必須(是或返回)由設備實現者選擇的值,以人類可讀的格式標識設備中使用的特定內部無線電/調製解調器版本。如果裝置沒有任何內部無線電/數據機,則它必須傳回 NULL。此欄位的值必須可編碼為 7 位元 ASCII,並符合正規表示式「^[a-zA-Z0-9._-,]+$」。

3.2.3.意圖相容性

3.2.3.1.核心應用意圖

Android 意圖允許應用程式元件向其他 Android 元件請求功能。 Android 上游項目包括被視為核心 Android 應用程式的應用程式列表,這些應用程式實現了多種意圖模式來執行常見操作。

  • [C-0-1] 對於 AOSP 中以下核心 Android 應用定義的所有公共 Intent 過濾器模式,裝置實作必須使用 Intent 處理程序預先載入一個或多個應用程式或服務元件:

    • 英式鐘
    • 瀏覽器
    • 日曆
    • 聯絡方式
    • 畫廊
    • 全球搜尋
    • 啟動器
    • 音樂
    • 設定
3.2.3.2.意圖解析
  • [C-0-1] 由於 Android 是可擴展平台,裝置實作必須允許第三方應用程式覆蓋第 3.2.3.1 節中引用的每個意圖模式。上游 Android 開源實作預設允許這樣做。
  • [C-0-2] 設備實現者不得為系統應用程式對這些意圖模式的使用賦予特殊權限,也不得阻止第三方應用程式綁定到這些模式並承擔對這些模式的控制。該禁止具體包括但不限於停用「選擇器」使用者介面,該介面允許使用者在全部處理相同意圖模式的多個應用程式之間進行選擇。

  • [C-0-3] 設備實作必須提供一個使用者介面,供使用者修改意圖的預設活動。

  • 但是,當預設活動為資料 URI 提供更具體的屬性時,裝置實作可以為特定 URI 模式(例如 http://play.google.com)提供預設活動。例如,指定資料 URI「http://www.android.com」的意圖過濾器模式比瀏覽器的「http://」核心意圖模式更具體。

Android 還包含一種機制,供第三方應用程式為某些類型的 Web URI 意圖聲明權威的預設應用程式連結行為。當在應用程式的意圖過濾器模式中定義此類權威聲明時,設備實作:

  • [C-0-4] 必須嘗試透過執行數位資產連結規範中定義的驗證步驟(由上游 Android 開源專案中的套件管理器實作)來嘗試驗證任何意圖過濾器。
  • [C-0-5] 必須在應用安裝期間嘗試驗證意圖過濾器,並將所有成功驗證的 UIR 意圖過濾器設定為其 UIR 的預設應用處理程序。
  • 如果成功驗證但其他候選 URI 過濾器驗證失敗,則可以將特定 URI 意圖過濾器設定為其 URI 的預設應用程式處理程序。如果裝置實作這樣做,它必須在設定選單中為使用者提供適當的每 URI 模式覆蓋。
  • 必須在設定中為使用者提供每個應用程式的應用程式連結控件,如下所示:
    • [C-0-6] 使用者必須能夠將應用程式的預設應用程式連結行為整體覆蓋為:始終開啟、始終詢問或從不打開,並且必須同等地應用於所有候選 URI 意圖過濾器。
    • [C-0-7] 使用者必須能夠查看候選 URI 意圖過濾器的清單。
    • 設備實作可以為使用者提供基於每個意圖過濾器覆蓋已成功驗證的特定候選 URI 意圖過濾器的能力。
    • [C-0-8] 如果裝置實作允許某些候選 URI 意圖過濾器成功驗證,而其他一些可能失敗,則裝置實作必須為使用者提供檢視和覆寫特定候選 URI 意圖過濾器的功能。
3.2.3.3.意圖命名空間
  • [C-0-1] 裝置實作不得包含任何使用 ACTION、CATEGORY 或 android.conf 檔案中的其他關鍵字串來支援任何新意圖或廣播意圖模式的 Android 元件。或com.android。命名空間。
  • [C-0-2] 裝置實現者不得包含任何使用 ACTION、CATEGORY 或屬於其他組織的套件空間中的其他關鍵字串來遵循任何新意圖或廣播意圖模式的 Android 元件。
  • [C-0-3] 設備實現者不得更改或擴展第 3.2.3.1 節中列出的核心應用使用的任何意圖模式。
  • 設備實作可以包括使用與其自己的組織明確相關的命名空間的意圖模式。該禁止類似於3.6 節中針對 Java 語言類別指定的禁止。
3.2.3.4.廣播意圖

第三方應用程式依靠平台廣播某些意圖,以通知它們硬體或軟體環境的變化。

設備實現:

  • [C-0-1] 必須廣播公共廣播意圖,以回應 SDK 文件中所述的適當系統事件。請注意,此要求與第 3.5 節並不衝突,因為 SDK 文件中也描述了後台應用程式的限制。
3.2.3.5.預設應用程式設定

Android 包含的設定可讓用戶輕鬆選擇預設應用程序,例如主螢幕或簡訊。

在有意義的情況下,設備實作必須提供類似的設定選單,並與 SDK 文件中所述的意圖過濾器模式和 API 方法相容,如下所示。

如果裝置實作報表android.software.home_screen ,則:

如果裝置實作報表android.hardware.telephony ,則:

如果裝置實作報表android.hardware.nfc.hce ,則:

如果裝置實作支援VoiceInteractionService ,並且使用該API一次安裝了多個應用程序,則它們:

3.2.4.輔助顯示的活動

如果設備實作允許在輔助顯示器上啟動正常的Android活動,則它們:

  • [C-1-1]必須設定android.software.activities_on_secondary_displays功能標誌。
  • [C-1-2] 必須確保 API 相容性,類似於在主顯示幕上執行的活動。
  • [C-1-3]必須將新活動與啟動其啟動的活動相同的顯示,而新活動是在不透過ActivityOptions.setLaunchDisplayId() API指定目標顯示的情況下啟動的。
  • [C-1-4]當有Display.FLAG_PRIVATE標誌的顯示時,必須銷毀所有活動。
  • [C-1-5]如果調整顯示本身,則必須相應地調整VirtualDisplay上的所有活動。
  • 當文字輸入欄位專注於輔助顯示時,可以在主顯示器上顯示IME(輸入方法編輯器,一個使用戶輸入文字的使用者控制項)。
  • 應在支援觸控或鍵輸入時獨立於主顯示器上的輸入重點。
  • 應具有與該顯示相對應的android.content.res.Configuration ,以便顯示,正確操作並保持相容性,如果在輔助顯示上啟動了活動。

如果裝置實作允許在輔助顯示上啟動正常的Android活動,並且主要和次要顯示具有不同的Android.util.displaymetrics

  • [C-2-1]不可避免的活動(在AndroidManifest.xml中具有resizeableActivity=false )和針對API等級23或更低的應用程式在輔助顯示時不得允許。

如果裝置實作允許在輔助顯示器上啟動正常的Android 活動,且輔助顯示器具有android.view.Display.FLAG_PRIVATE標誌:

  • [C-3-1] 只有該顯示、系統以及該顯示上已存在的活動的擁有者才能夠啟動該顯示。每個人都可以啟動具有android.view.Display.FLAG_PUBLIC標誌的顯示器。

3.3.本機 API 相容性

設備實現者是:

本機程式碼相容性具有挑戰性。因此,設備實現者是:

  • [SR]強烈建議使用下游Android開源專案中列出的程式庫的實作。

3.3.1.應用程式二進位接口

託管的dalvik位元組碼可以在應用程式.apk檔案中提供的本機程式碼,作為用於適當的裝置硬體體系結構的ELF .so檔案。由於本機程式碼高度依賴底層處理器技術,Android 在 Android NDK 中定義了許多應用程式二進位介面 (ABI)。

設備實現:

  • [C-0-1]必須與一個或多個定義的ABI相容,並與Android NDK實現相容性。
  • [C-0-2] 必須支援在託管環境中執行的程式碼,以使用標準 Java 本機介面 (JNI) 語意呼叫本機程式碼。
  • [C-0-3] 必須與下面列表中每個必需的庫來源相容(即標頭相容)和二進位相容(對於 ABI)。
  • [C-0-4]如果支援任何64位元ABI,則必須支援等效的32位元ABI。
  • [C-0-5] MUST accurately report the native Application Binary Interface (ABI) supported by android.os.Build.SUPPORTED_64_BIT_ABIS device, via the android.os.Build.SUPPORTED_ABIS , android.os.Build.SUPPORTED_32_BIT_ABIS para.P.A.S.S. ,每個逗號分開的ABIS列表從最多到最不受歡迎的列表。
  • [C-0-6]必須透過上述參數報告,只有在Android NDK ABI管理文件的最新版本中記錄和描述的ABI,並且必須包括對高級SIMD (AKA NEON)擴展的支援。
  • [C-0-7] 必須讓下列所有提供本機 API 的函式庫可供包含本機程式碼的應用程式使用:

    • libaaudio.so(AAudio 原生音訊支援)
    • libandroid.so(原生 Android 活動支援)
    • libc(C 庫)
    • libcamera2ndk.so
    • libdl(動態連結器)
    • libEGL.so(原生 OpenGL 表面管理)
    • libGLESv1_CM.so (OpenGL ES 1.x)
    • libGLESv2.so(OpenGL ES 2.0)
    • libGLESv3.so (OpenGL ES 3.x)
    • libicui18n.so
    • 庫克庫克
    • libjnigraphics.so
    • liblog(Android 日誌記錄)
    • libmediandk.so(原生媒體 API 支援)
    • libm(數學庫)
    • libOpenMAXAL.so(OpenMAX AL 1.0.1 支援)
    • libOpenSLES.so(OpenSL ES 1.0.1 音訊支援)
    • libRS.so
    • libstdc++(對 C++ 的最低支援)
    • libvulkan.so(Vulkan)
    • libz(Zlib 壓縮)
    • JNI介面
  • [C-0-8] 不得新增或刪除上面列出的本機庫的公共函數。

  • [C-0-9]必須列出其他直接暴露於/vendor/etc/public.libraries.txt中的第三方應用程式的非AOSP程式庫。
  • [C-0-10] 不得將在 AOSP 中作為系統函式庫實作和提供的任何其他本機函式庫暴露給面向 API 等級 24 或更高等級的第三方應用,因為它們是保留的。
  • [C-0-11]必須透過libGLESv3.so函式庫匯出所有OpenGL ES 3.1和Android擴充包函數符號。請注意,雖然所有符號都必須存在,但第 7.1.4.1 節更詳細地描述了預期每個相應功能的完整實現的要求。
  • [C-0-12] MUST export function symbols for the core Vulkan 1.0 function symobls, as well as the VK_KHR_surface , VK_KHR_android_surface , VK_KHR_swapchain , VK_KHR_maintenance1 , and VK_KHR_get_physical_device_properties2 extensions through the libvulkan.so library.請注意,雖然所有符號都必須存在,但第 7.1.4.2 節更詳細地描述了預期每個相應功能的完整實現的要求。
  • 應使用上游Android開源專案中可用的原始程式碼和標頭檔案來構建

請注意,Android NDK 的未來版本可能會引入對其他 ABI 的支援。

3.3.2. 32 位元 ARM 本機程式碼相容性

如果設備實作是64位元ARM設備,則:

  • [C-1-1]儘管ARMV8體系結構棄用了多個CPU操作,包括現有本機程式碼中使用的某些操作,但必須透過本機CPU支援或透過軟體模擬可用於32位元本機ARM程式碼的以下棄用操作:

    • SWP和SWPB說明
    • 設定指令
    • CP15ISB,CP15DSB和CP15DMB屏障操作

如果設備實作包括32位元ARM ABI,則它們:

  • [C-2-1]在32位元ARM應用程式讀取時,必須在/proc/cpuinfo中包含以下行,以確保與使用Android NDK的舊版建立的應用程式相容。

    • Features: ,然後是該裝置支援的任何選用ARMV7 CPU功能的清單。
    • CPU architecture:接著是描述設備最高支撐的ARM架構的整數(例如,對於ARMV8設備,「 8」)。
  • 透過64位元ARM或非ARM應用程式閱讀時,不應更改/proc/cpuinfo

3.4.網路相容性

3.4.1.網頁視圖相容性

如果裝置實作提供了android.webkit.Webview API的完整實現,則它們:

  • [C-1-1]必須報告android.software.webview
  • [C-1-2]必須使用Android 8.1分支的上游Android開源專案的Chromium Project Build,以實作android.webkit.WebView API。
  • [C-1-3] WebView 報表的使用者代理字串必須採用以下格式:

    Mozilla/5.0(Linux; Android $(版本); $(型號)build/$(build); wv)AppleWebkit/537.36(Khtml,像Gecko)版本/4.0 $(Chromium_ver)Mobile Safari/537.36

    • $(VERSION) 字串的值必須與 android.os.Build.VERSION.RELEASE 的值相同。
    • $(型號)字串的值必須與android.os.os.build.model的值相同。
    • $(build)字串的值必須與android.os.build.id的值相同。
    • $(CHROMIUM_VER) 字串的值必須是上游 Android 開源專案中 Chromium 的版本。
    • 設備實作可以在用戶代理字串中省略 Mobile。
  • WebView 元件應該包含對盡可能多的 HTML5 功能的支持,並且如果它支援該功能,則應該符合HTML5 規範

3.4.2.瀏覽器相容性

如果設備實作包括用於一般 Web 瀏覽的獨立瀏覽器應用程序,則它們:

  • [C-1-1] 必須支援與 HTML5 關聯的每個 API:
  • [C-1-2] 必須支援 HTML5/W3C Webstorage API並應支援 HTML5/W3C IndexedDB API 。請注意,隨著 Web 開發標準機構逐漸轉向支援 IndexedDB 而不是 Webstorage,IndexedDB 預計將成為 Android 未來版本中的必要組件。
  • 可以在獨立的瀏覽器應用程式中提供自訂使用者代理字串。
  • 應在獨立瀏覽器應用程式上實現對盡可能多的HTML5的支援(無論是基於上游 WebKit 瀏覽器應用程式還是第三方替代方案)。

但是,如果設備實作不包括獨立的瀏覽器應用程序,則它們:

3.5. API 行為相容性

每個 API 類型(託管、軟體、本機和 Web)的行為必須與上游Android 開源專案的首選實作一致。一些特定的兼容性領域是:

  • [C-0-1] 設備不得更改標準意圖的行為或語意。
  • [C-0-2] 設備不得更改特定類型的系統元件(例如服務、活動、ContentProvider 等)的生命週期或生命週期語意。
  • [C-0-3] 設備不得更改標準權限的語意。
  • 設備不得改變對背景應用程式實施的限制。更具體地說,對於後台應用程式:
    • [C-0-4]他們必須停止執行該應用程式註冊的回調,以從GnssMeasurementGnssNavigationMessage接收輸出。
    • [C-0-5]他們必須透過LocationManager API類別或WifiManager.startScan()方法對應用程式提供的更新頻率進行評分。
    • [C-0-6]如果該應用程式針對API等級25或更高,則它們不得允許在應用程式清單中為標準Android意圖的隱式廣播註冊廣播接收器,除非廣播意圖需要"signature""signatureOrSystem" protectionLevel許可或在豁免清單中。
    • [C-0-7]如果該應用程式針對API等級25或更高,則必須停止應用程式的背景服務,就像該應用程式稱為stopSelf()方法一樣,除非將應用程式放置在臨時允許清單上處理使用者可見的任務。
    • [C-0-8] 如果套用的目標 API 等級為 25 或更高,則它們必須釋放應用程式所持有的喚醒鎖定。

上面的列表並不全面。相容性測試套件 (CTS) 測試平台的重要部分(但不是全部)的行為相容性。實作者有責任確保與 Android 開源專案的行為相容性。因此,裝置實現者應該盡可能使用透過 Android 開源專案提供的原始程式碼,而不是重新實作系統的重要部分。

3.6. API命名空間

Android 遵循 Java 程式語言定義的套件和類別命名空間約定。為了確保與第三方應用程式的相容性,裝置實作者不得對這些套件命名空間進行任何禁止的修改(見下文):

  • java.*
  • javax.*
  • sun.*
  • android.*
  • com.android.*

也就是說,他們:

  • [C-0-1] 不得透過更改任何方法或類別簽名,或刪除類別或類別欄位來修改 Android 平台上公開公開的 API。
  • [C-0-2] 不得在上述命名空間中的 API 中新增任何公開的元素(例如類別或接口,或現有類別或接口的欄位或方法)或測試或系統 API。 「公開暴露的元素」是指未使用上游 Android 原始碼中使用的「@hide」標記修飾的任何構造。

設備實現者可以修改 API 的底層實現,但此類修改:

  • [C-0-3]不得影響任何公開暴露的API的既定行為和Java語言簽名。
  • [C-0-4]不得向開發人員做廣告或以其他方式接觸。

但是,裝置實作者可以在標準Android名稱空間之外新增自訂API,但自訂API:

  • [C-0-5]不得在另一個組織擁有或指涉另一個組織的命名空間中。例如,裝置實現者不得將API新增至com.google.*或類似的名稱空間:只有Google可以這樣做。同樣,Google 不得將 API 新增至其他公司的命名空間。
  • [C-0-6]必須在Android共享庫中打包,以便只有明確使用它們的應用程式(透過<susta-library>機制)受到此類API的記憶體使用的增加影響。

如果設備實現者建議改進上述包命名空間之一(例如透過向現有 API 添加有用的新功能,或添加新 API),則實現者應該訪問source.android.com並開始貢獻更改和的過程代碼,根據該網站上的信息。

請注意,上述限制對應於 Java 程式語言中命名 API 的標準約定;本節的目的只是為了加強這些約定,並透過將其納入此相容性定義來使其具有約束力。

3.7.運行時相容性

設備實現:

  • [C-0-1] 必須支援完整的 Dalvik 執行檔 (DEX) 格式以及Dalvik 字節碼規格和語意

  • [C-0-2] 必須將 Dalvik 運行時配置為根據上游 Android 平台並按下表的指定分配記憶體。 (有關螢幕尺寸和螢幕密度定義,請參閱第 7.1.1 節。)

  • 應使用 Android RunTime (ART)、Dalvik 可執行格式的參考上游實作以及參考實作的套件管理系統。

  • 應在各種執行模式和目標架構下執行模糊測試,以確保運行時的穩定性。請參閱 Android 開源專案網站中的JFuzzDexFuzz

請注意,下面指定的記憶體值被視為最小值,設備實作可以為每個應用程式分配更多記憶體。

螢幕佈局螢幕密度最小應用記憶體
安卓手錶120 dpi(LDPI) 32MB
160 dpi (mdpi)
213 dpi(電視dpi)
240 dpi(高清) 36MB
280dpi (280dpi)
320 dpi(xhdpi) 48MB
360dpi (360dpi)
400dpi (400dpi) 56MB
420 dpi (420dpi) 64MB
480 dpi (xxhdpi) 88MB
560dpi(560dpi) 112MB
640 dpi (xxxhdpi) 154MB
小/正常120 dpi(LDPI) 32MB
160 dpi (mdpi)
213 dpi(電視dpi) 48MB
240 dpi(高清)
280dpi (280dpi)
320 dpi(xhdpi) 80MB
360dpi (360dpi)
400dpi (400dpi) 96MB
420 dpi (420dpi) 112MB
480 dpi (xxhdpi) 128MB
560dpi(560dpi) 192MB
640 dpi (xxxhdpi) 256MB
大的120 dpi(LDPI) 32MB
160 dpi (mdpi) 48MB
213 dpi(電視dpi) 80MB
240 dpi(高清)
280dpi (280dpi) 96MB
320 dpi(xhdpi) 128MB
360dpi (360dpi) 160MB
400dpi (400dpi) 192MB
420 dpi (420dpi) 228MB
480 dpi (xxhdpi) 256MB
560dpi(560dpi) 384MB
640 dpi (xxxhdpi) 512MB
超大120 dpi(LDPI) 48MB
160 dpi (mdpi) 80MB
213 dpi(電視dpi) 96MB
240 dpi(高清)
280dpi (280dpi) 144MB
320 dpi(xhdpi) 192MB
360dpi (360dpi) 240MB
400dpi (400dpi) 288MB
420 dpi (420dpi) 336MB
480 dpi (xxhdpi) 384MB
560dpi(560dpi) 576MB
640 dpi (xxxhdpi) 768MB

3.8.使用者介面相容性

3.8.1.啟動器(主螢幕)

Android 包括啟動器應用程式(主畫面)並支援第三方應用程式來取代裝置啟動器(主畫面)。

如果設備實現允許第三方應用程式替換設備主螢幕,則它們:

  • [C-1-1]必須聲明平台功能android.software.home_screen
  • [C-1-2]當第三方應用程式使用<adaptive-icon>標籤提供其圖示時,必須返回AdaptiveIconDrawable對象,並且呼叫了檢索圖示的PackageManager方法。

如果裝置實作包含支援應用程式內固定快捷方式的預設啟動器,則它們:

相反,如果裝置實作不支援應用程式內固定快捷方式,則:

如果裝置實作實作了預設啟動器,可透過ShortcutManager API 快速存取第三方應用程式提供的其他捷徑,則:

  • [C-4-1]必須支援所有已記錄的快捷方式(例如靜態和動態快捷方式,固定快捷方式),並完全實現ShortcutManager API類的API。

如果裝置實作包括顯示應用程式圖示徽章的預設啟動器應用程序,則它們:

  • [C-5-1]必須尊重NotificationChannel.setShowBadge() API方法。換句話說,如果該值設為true ,則顯示與應用程式圖示相關的視覺負擔性,並且當所有應用程式的通知頻道都將值設為false時,請勿顯示任何應用圖示徽章方案。
  • 當第三方應用程式透過使用專有 API 表示支援專有徽章方案時,可以使用其專有徽章方案覆蓋應用程式圖示徽章,但應使用透過SDK中描述的通知徽章 API 提供的資源和值,例如Notification.Builder.setNumber()Notification.Builder.setBadgeIconType() API。

3.8.2.小部件

Android 透過定義元件類型以及對應的 API 和生命週期來支援第三方應用程式小工具,從而允許應用程式向最終用戶公開「AppWidget」

如果設備實作支援第三方應用程式小部件,則它們:

  • [C-1-1]必須聲明對平台功能android.software.app_widgets的支援。
  • [C-1-2]必須包括對AppWidgets的內建支持,並將使用者介面提供直接在啟動器中直接添加,配置,查看和刪除AppWidgets的服務。
  • [C-1-3] 必須能夠渲染標準網格大小為 4 x 4 的微件。有關詳細信息,請參閱 Android SDK 文件中的App Widget DesignGuidelines
  • 可以支援鎖定螢幕上的應用程式小工具。

如果裝置實作支援第三方應用程式小工具和應用程式內固定快捷方式,則它們:

3.8.3.通知

Android包括NotificationNotificationManager API,允許第三方應用程式開發人員使用硬體元件(例如聲音,振動和光線)和軟體功能(例如通知陰影,系統列)通知用戶著名事件,並吸引用戶的注意。

3.8.3.1.通知的呈現

如果設備實現允許第三方應用程式通知用戶著名事件,則他們:

  • [C-1-1] 必須支援使用硬體功能的通知(如 SDK 文件所述),並盡可能支援裝置實現硬體。例如,如果裝置實作包含振動器,則它必須正確實作振動 API。如果設備實作缺少硬件,則對應的 API 必須實作為無操作。此行為在第 7 節中有進一步詳細介紹。
  • [C-1-2]必須正確渲染API中提供的所有資源(圖標,動畫文件等),或在狀態/系統欄圖標樣式指南中,儘管它們可以為通知提供替代的用戶體驗通過參考Android開源實現。
  • [C-1-3] 必須遵守並正確實施API更新、刪除和分組通知所描述的行為。
  • [C-1-4] 必須提供 SDK 中記錄的NotificationChannel API 的完整行為。
  • [C-1-5] 必須讓使用者能夠依照每個管道和應用程式套件層級封鎖和修改特定第三方應用程式的通知。
  • [C-1-6] 也必須讓使用者顯示已刪除的通知管道。
  • 應支援豐富的通知。
  • 應將一些較高優先順序的通知作為抬頭通知呈現。
  • 用戶應該能夠暫停通知。
  • 只能管理第三方應用程式何時能夠通知用戶著名事件的可見性和時機,以減輕諸如駕駛員分心之類的安全問題。

如果設備實現支援豐富的通知,則它們:

  • [C-2-1]必須使用Notification.Style類別提供的確切資源及其用於提出的資源元素的子類別。
  • 應介紹通知中定義的每個資源元素(例如圖標,標題和摘要文字)。 Notification.Style API類別及其子類別。

如果設備實現支援主題通知:它們:

  • [C-3-1]必須按照通知中所述的主題通知視圖和資源。 Notification.Builder API類別何時提出通知。
3.8.3.2.通知監聽服務

Android包括允許應用程式(一旦用戶明確啟用了)的NotificationListenerService API,可以在發布或更新時接收所有通知的副本。

如果裝置實作報表功能flag android.hardware.ram.normal ,則它們:

  • [C-1-1]必須正確且迅速地將通知完整地更新為所有此類安裝和啟用使用者的偵聽器服務,包括附加到通知對象的所有元資料。
  • [C-1-2]必須尊重snoozeNotification() API呼叫,並駁回通知並在API呼叫中設定的貪睡持續時間後進行回調。

如果設備實作允許使用者暫停通知,那麼它們:

  • [C-2-1]必須透過標準API(例如NotificationListenerService.getSnoozedNotifications()正確地反映了通知狀態。
  • [C-2-2]必須使此使用者負擔能力可用於從每個安裝的第三方應用程式中的snooze通知,除非它們來自持久/前景服務。
3.8.3.3. DND(請勿打擾)

如果設備實現支援 DND 功能,則:

  • [C-1-1]必須實施一項將回應意圖action_notification_policy_access_settings的活動,該活動對於使用UI_MODE_TYPE_NORMAL實現,它必須是一項活動,使用者可以授予或拒絕應用程式存取DND策略配置的活動。
  • [C-1-2]必須,對於設備實施提供了一種手段,用戶可以授予或拒絕第三方應用程式訪問DND策略配置時,請顯示由應用程式與用戶創建的應用程式創建的自動DND規則-定義的規則。
  • [C-1-3]必須遵守沿著NotificationManager.Policy suppressedVisualEffects值,並且如果應用程式設定了任何dustresse_effect_screen_off或dustrese_effect_screen_on標誌,則應向使用者表明在DND設定選單中抑制視覺效果。

Android包含API,使開發人員可以將搜尋納入其應用程式中,並將其應用程式的資料曝光到全球系統搜尋。一般來說,此功能由單一系統範圍的使用者介面組成,允許使用者輸入查詢、在使用者鍵入時顯示建議並顯示結果。 Android API允許開發人員重複使用此介面以在自己的應用程式中提供搜索,並允許開發人員為常見的全域搜尋使用者介面提供結果。

  • Android設備實現應包括全局搜索,一個單一,共享的,系統範圍的搜索用戶界面,能夠響應用戶輸入來實時建議。

如果設備實現實現了全域搜尋接口,則它們:

  • [C-1-1]必須實作允許第三方應用程式以全域搜尋模式運行時將建議新增至搜尋框的API。

如果沒有安裝使用全域搜尋的第三方應用程式:

  • 預設行為應該是顯示Web搜尋引擎結果和建議。

Android還包括輔助API ,以允許應用程式選擇與裝置上的助理共享目前上下文的多少資訊。

如果設備實現支援協助操作,則它們:

  • [C-2-1] 必須透過以下任一方式向最終使用者明確指示何時分享情境:
    • 每次輔助應用程式存取上下文時,都會在螢幕邊緣周圍顯示白光,該白光滿足或超過 Android 開源專案實現的持續時間和亮度。
    • 對於預先安裝的輔助應用程序,為使用者提供離開預設語音輸入和輔助應用程式設定選單少於兩次導航的功能,並且僅在使用者透過熱詞或輔助導航鍵輸入明確呼叫輔助應用程式時共享上下文。
  • [C-2-2]依照第7.2.3節所述啟動輔助應用程式的指定互動必須啟動使用者選擇的輔助應用程序,換句話說,實作VoiceInteractionService的應用程式或處理ACTION_ASSIST意圖的活動。
  • [SR]強烈建議在HOME鍵上使用Long Press作為指定的交互作用。

3.8.5。警報和祝酒詞

應用程式可以使用Toast API向最終用戶顯示簡短的非模式字串,該字串在短時間後消失,並使用TYPE_APPLICATION_OVERLAY視窗類型API將警報Windows顯示為對其他應用程式的覆蓋。

如果設備實作包括螢幕或視訊輸出,則它們:

  • [C-1-1]必須提供一個使用者負擔,以阻止應用程式顯示使用TYPE_APPLICATION_OVERLAY警報視窗。 AOSP 實作透過在通知欄中設定控制項來滿足此要求。

  • [C-1-2] 必須遵守 Toast API,並以某種高度可見的方式從應用程式向最終用戶顯示 Toast。

3.8.6。主題

Android 提供「主題」作為應用程式在整個 Activity 或應用程式中應用樣式的機制。

Android 包含「Holo」和「Material」主題系列作為一組定義的樣式,供應用程式開發人員在想要匹配 Android SDK 定義的Holo 主題外觀和感覺時使用。

如果設備實作包括螢幕或視訊輸出,則它們:

  • [C-1-1] 不得更改向應用程式公開的任何Holo 主題屬性
  • [C-1-2] 必須支援「Material」主題系列,並且不得更改任何Material 主題屬性或其向應用程式公開的資產。

Android 還包含一個「裝置預設」主題系列,作為一組定義的樣式,供應用程式開發人員在想要匹配裝置實現者定義的裝置主題的外觀和風格時使用。

Android 支援具有半透明系統列的變體主題,允許應用程式開發人員使用其應用程式內容填充狀態列和導覽列後面的區域。為了在此配置中實現一致的開發人員體驗,在不同的裝置實作中保持狀態列圖示樣式非常重要。

如果設備實作包含系統狀態欄,則:

  • [C-2-1]必須將白色用於系統狀態圖示(例如訊號強度和電池電量等級)和系統發出的通知,除非圖示表示有問題的狀態或應用程式要求使用Sytem_UI_FLAG_FLAG_STATUS_BAR FLAG 。
  • [C-2-2] 當應用程式請求淺色狀態列時,Android 裝置實作必須將系統狀態圖示的顏色變更為黑色(有關詳細信息,請參閱R.style )。

3.8.7.動態壁紙

Android 定義了一種元件類型以及相應的 API 和生命週期,允許應用程式向最終用戶公開一個或多個「動態桌布」 。動態壁紙是動畫、圖案或具有有限輸入功能的類似圖像,在其他應用程式後面顯示為壁紙。

如果硬體能夠以合理的幀速率運行所有動態壁紙,且沒有功能限制,並且不會對其他應用程式產生不利影響,則該硬體被認為能夠可靠地運行動態壁紙。如果硬體限制導致壁紙和/或應用程式崩潰、故障、消耗過多的 CPU 或電池電量,或以不可接受的低幀速率運行,則該硬體被視為無法運行動態壁紙。例如,某些動態桌布可能使用 OpenGL 2.0 或 3.x 上下文來渲染其內容。動態桌布將無法在不支援多個 OpenGL 上下文的硬體上可靠地運行,因為使用 OpenGL 上下文的動態桌布可能會與也使用 OpenGL 上下文的其他應用程式發生衝突。

  • 如上所述,能夠可靠地運行動態壁紙的設備實現應該實現動態壁紙。

如果設備實現實現了動態壁紙,那麼它們:

  • [C-1-1] 必須報告平台功能標誌 android.software.live_wallpaper。

3.8.8.活動切換

上游 Android 原始程式碼包括概覽畫面、系統級使用者介面,用於任務切換以及使用使用者上次離開應用程式時應用程式圖形狀態的縮圖顯示最近造訪的活動和任務。

裝置實作(包括第 7.2.3 節中詳述的最近功能導航鍵)可能會變更介面。

如果裝置實作(包括第 7.2.3 節中詳述的最近功能導航鍵)改變了介面,則:

  • [C-1-1] 必須支援至少 7 個顯示的活動。
  • 應至少一次顯示 4 個活動的標題。
  • [C-1-2] 必須實現螢幕固定行為,並提供使用者用於切換該功能的設定選單。
  • 應顯示最近的突出顯示顏色、圖示、螢幕標題。
  • 應顯示關閉可供性(“x”),但可以延遲顯示,直到使用者與螢幕互動。
  • 應該實現快捷方式以輕鬆切換到先前的活動
  • 當最近使用的功能鍵被點擊兩次時,應該會觸發兩個最近使用的應用程式之間的快速切換操作。
  • 當長按最近使用的功能鍵時,如果支持,應該觸發分割畫面多視窗模式。
  • 可以將關聯的最近內容顯示為一起移動的群組。

  • 強烈建議[SR]用於概述螢幕上游Android使用者介面(或類似的基於縮圖的介面)。

3.8.9。輸入管理

Android 包括對輸入管理的支援以及對第三方輸入法編輯器的支援。

如果設備實現允許用戶在設備上使用第三方輸入法,則他們:

  • [C-1-1] 必須聲明平台功能 android.software.input_methods 並支援 Android SDK 文件中定義的 IME API。
  • [C-1-2]必須提供可存取和配置第三方輸入方法的使用者存取機制,以回應android.settings.input_method_settings意圖。

如果裝置實作聲明android.software.autofill功能標誌,則它們:

3.8.10.鎖定螢幕媒體控制

從 Android 5.0 開始,遠端控制用戶端 API 已被棄用,取而代之的是媒體通知模板,該模板允許媒體應用程式與鎖定螢幕上顯示的播放控制項整合。

3.8.11.螢幕保護程式(以前的夢想)

Android包括對InteractivesCreensavers的支持,以前稱為夢。當連接到電源來源的裝置空閒或停靠在桌上碼頭時,螢幕保護程式允許使用者與應用程式互動。 Android Watch裝置可以實現螢幕保護程序,但其他類型的裝置實作應包括對螢幕保護程式的支持,並為使用者提供設定選項,以回應android.settings.DREAM_SETTINGS意圖。

3.8.12.地點

如果設備實作包括能夠提供位置座標的硬體感測器(例如GPS):

  • [C-1-1]必須在設定中的位置選單中顯示位置模式

3.8.13.統一碼和字體

Android 支援Unicode 10.0中定義的表情符號字元。

如果設備實作包括螢幕或視訊輸出,則它們:

  • [C-1-1] 必須能夠以彩色字形呈現這些表情符號字元。
  • [C-1-2] 必須支援:
  • Roboto 2 font with different weights—sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black, sans-serif-condensed, sans-serif-condensed-light for the languages available on the裝置.
  • Unicode 7.0 完全涵蓋拉丁文、希臘文和西里爾文,包括拉丁文擴展 A、B、C 和 D 範圍,以及 Unicode 7.0 貨幣符號區塊中的所有字形。
  • 應支持Unicode 技術報告 #51中指定的膚色和多樣化的家庭表情符號。

如果裝置實作包含 IME,則:

  • 應為使用者提供這些表情符號的輸入方法。

3.8.14.多視窗

如果設備實作能夠同時顯示多個活動,那麼它們:

  • [C-1-1] 必須根據 Android SDK多視窗模式支援文件中所述的應用行為和 API 實作此類多視窗模式,並滿足以下要求:
  • [C-1-2]應用程式可以指示它們是否能夠透過設定AndroidManifest.xml android:resizeableActivity屬於true或隱式屬性,或透過擁有目標Sdkversion> 24. 24. 24.明確將此屬性設為false在其清單中不得以多視窗模式啟動。具有targetsdkversion <24的較舊的應用程式可以在多視窗模式下啟動該android:resizeableActivity屬性,但是該系統必須警告該應用程式在多視窗模式下可能無法按預期工作。
  • [C-1-3]如果螢幕高度<440 dp且螢幕寬度<440 dp,則不得提供分割畫面或自由形式模式。
  • 具有螢幕尺寸xlarge裝置實作應支援自由形式模式。

如果設備實現支援多視窗模式和分割螢幕模式,則它們:

  • [C-2-1]必須將可重件的啟動器預先載入為預設值。
  • [C-2-2] 必須裁切分割畫面多視窗的停靠 Activity,但如果啟動器應用是焦點窗口,則應顯示其中的部分內容。
  • [C-2-3]必須尊重已聲明的AndroidManifestLayout_minWidth和第三方啟動器應用程式的AndroidManifestLayout_minHeight值,而不是在顯示對接活動的某些內容的過程中覆寫這些值。

如果設備實現支援多視窗模式和圖片中的多視窗模式,則它們:

  • [C-3-1]當應用程式為: *針對API級別26或更高並聲明android:supportsPictureInPicture *針對API級別25或更低級別,並聲明兩者android:resizeableActivityandroid:supportsPictureInPicture
  • [C-3-2]必須依照目前的PIP活動透過setActions() API來揭示其係統中的動作。
  • [C-3-3]必須支援大於或等於1:2.39且小於或等於2.39:1的寬高比,如PIP活動透過setAspectRatio() API所指定的。
  • [C-3-4]必須使用KeyEvent.KEYCODE_WINDOW來控制PIP視窗;如果未實現 PIP 模式,則該金鑰必須可供前台活動使用。
  • [C-3-5] 必須讓使用者能夠阻止應用程式以 PIP 模式顯示; AOSP 實作透過在通知欄中設定控制項來滿足此要求。
  • [C-3-6]必須為PIP視窗分配最小寬度UI_MODE_TYPE_TELEVISION 108 dp的最小寬度和高度為240 dp的最小寬度,並為Configuration.uiMode視窗分配135 dp的高度。

3.9.設備管理

Android包含允許安全感知應用程式在系統層級執行裝置管理功能的功能,例如透過Android裝置管理API執行密碼原則或執行遠端清除]。

如果裝置實作實現了 Android SDK 文件中定義的全部裝置管理策略,那麼它們:

  • [C-1-1]必須聲明android.software.device_admin
  • [C-1-2] 必須支援設備擁有者配置,如第 3.9.1 節第 3.9.1.1 節所述。
  • [C-1-3]必須透過android.software.managed_users功能標誌聲明對管理設定檔的支持,除非裝置設定何時將其報告為低RAM設備,否 - 可移動)儲存為共用儲存。

3.9.1 準備配置

3.9.1.1 設備所有者配置

如果裝置實作聲明android.software.device_admin ,則它們:

如果裝置實作聲明android.software.device_admin ,但也包括專有裝置擁有者管理解決方案,並提供了一種機制,以促進其解決方案中配置為標準「裝置擁有者」的應用程式的應用程序,並由標準Android DevicePolicyManager API,它們:

  • [C-2-1]必須制定一個流程來驗證被提升的特定應用程式是否屬於合法的企業設備管理解決方案,並且已經在專有解決方案中配置了它,以使權利等效為「設備所有者” 。
  • [C-2-2]必須顯示與android.app.action.PROVISION_MANAGED_DEVICE在註冊DPC應用程式之前作為「裝置擁有者」之前的Android.provision_managed_device發起的流量相同的AOSP裝置擁有者同意揭露。
  • 在將DPC應用程式註冊為「裝置擁有者」之前,可能在裝置上具有使用者資料。
3.9.1.2 託管設定檔配置

如果裝置實作聲明android.software.managed_users ,則它們:

  • [C-1-1] 必須實作允許裝置原則控制器 (DPC) 應用程式成為新託管設定檔的擁有者的API

  • [C-1-2]使用者經驗的託管設定檔設定流程(由Android.app.action.provision_managed_profile啟動的流程)必須與AOSP實作保持一致。

  • [C-1-3] 必須在設定中提供以下使用者功能,以便在裝置原則控制器 (DPC) 停用特定係統功能時向使用者指示:

    • 一致的圖示或其他使用者可供性(例如上游 AOSP 資訊圖示),用於表示特定設定何時受到設備管理員的限制。
    • 由設備管理員透過setShortSupportMessage提供的簡短說明訊息。
    • DPC 應用程式的圖示。

3.9.2 託管設定檔支持

如果裝置實作聲明android.software.managed_users ,則它們:

  • [C-1-1]必須透過android.app.admin.DevicePolicyManager API來支援託管設定檔。
  • [C-1-2] 必須允許建立一個且僅一個託管設定檔
  • [C-1-3] 必須使用圖標徽章(類似於 AOSP 上游工作徽章)來表示託管應用程式和微件以及其他帶有徽章的 UI 元素(例如「最近」和「通知」)。
  • [C-1-4] 必須顯示通知圖示(類似 AOSP 上游工作徽章)以指示使用者何時位於託管設定檔應用程式中。
  • [C-1-5] 如果裝置喚醒 (ACTION_USER_PRESENT) 且前台應用程式位於託管設定檔中,則必須顯示一個訊息框,指示使用者位於託管設定檔中。
  • [C-1-6] 如果存在託管設定文件,則必須在意圖「選擇器」中顯示視覺提示,以允許用戶將意圖從託管設定檔轉送到主用戶,反之亦然(如果裝置策略已啟用)控制器。
  • [C-1-7] 如果存在託管設定文件,則必須為主用戶和託管設定檔公開以下使用者功能:
    • 單獨核算主要使用者和託管設定檔的電池、位置、行動資料和儲存使用情況。
    • 獨立管理安裝在主要使用者或託管設定檔中的 VPN 應用程式。
    • 獨立管理安裝在主用戶或託管設定檔中的應用程式。
    • 對主要使用者或託管設定檔中的帳戶進行獨立管理。
  • [C-1-8] 必須確保預先安裝的撥號器、聯絡人和訊息應用程式可以從託管設定檔(如果存在)以及主設定檔中的資訊中搜尋並尋找呼叫者資訊(如果裝置原則控制器允許)。
  • [C-1-9] 必須確保它符合適用於啟用了多個使用者的裝置的所有安全要求(請參閱第 9.5 節),即使託管設定檔不被計為除主使用者之外的其他使用者。
  • [C-1-10]必須支援指定單獨的鎖定畫面滿足以下要求的能力,以授予對託管設定檔中執行的應用程式的存取。
  • 當託管設定檔中的聯絡人顯示在預先安裝的通話記錄、通話中UI、進行中和未接來電通知、聯絡人和訊息應用程式中時,他們應該使用與指示託管設定檔應用程式相同的徽章。

3.10.無障礙

Android提供了一個可訪問性層,可幫助殘疾用戶更輕鬆地導航其裝置。此外,Android還提供了平台API,使可訪問性服務實現能夠接收用於用戶和系統事件的回調,並產生替代的反饋機制,例如文字轉語音,觸覺反饋以及軌跡球/D-Pad導航。

如果設備實施支援第三方可訪問性服務,則它們:

  • [C-1-1]必須如訪問性API SDK文件中所述提供Android可訪問性框架的實作。
  • [C-1-2]必須產生可存取性事件,並為SDK中記錄的所有註冊AccessibilityService實作提供適當的AccessibilityEvent
  • [C-1-3]必須尊重android.settings.ACCESSIBILITY_SETTINGS目的是提供可存取使用者的機制,以啟用和停用第三方可存取性服務,並在預先載入的可存取性服務上。
  • [C-1-4]必須在系統的導覽列中新增一個按鈕,讓使用者在啟用存取性服務聲明存取性服務時控制可存取AccessibilityServiceInfo.FLAG_REQUEST_ACCESSIBILITY_BUTTON服務。請注意,對於沒有系統導覽列的設備實現,此要求不適用,但是設備實現應提供使用者負擔來控制這些可訪問性服務。

如果設備實作包括預先載入的可存取性服務,則它們:

  • [C-2-1]當資料儲存使用基於檔案的加密(FBE)加密時,必須將這些預先載入的可存取性服務作為直接啟動資訊應用程式。
  • 應在離式設定流中提供一種機制,以供使用者啟用相關的可訪問性服務,以及調整字體尺寸,顯示尺寸和放大倍率的選項。

3.11.文字轉語音

Android包括允許應用程式使用文字轉語音(TTS)服務的API,並允許服務提供者提供TTS服務的實現。

如果裝置實現報告功能android.hardware.audio.output,則它們:

如果設備實現支援安裝第三方TTS引擎,則它們:

  • [C-2-1] 必須提供使用者可供選擇的 TTS 引擎以在系統層級使用。

3.12.電視輸入框架

Android電視輸入框架(TIF)簡化了直播內容到Android電視裝置的交付。 TIF提供了一個標準API來建立控制Android電視裝置的輸入模組。

如果設備實現支援TIF,則它們:

  • [C-1-1]必須聲明平台功能android.software.live_tv
  • [C-1-2]必須預先載入電視應用程式(電視應用程式),並符合第3.12.1節所述的所有要求。

3.12.1.電視應用程式

如果設備實現支援TIF:

  • [C-1-1]電視應用必須提供安裝和使用電視頻道並符合以下要求的設施:

Android裝置實作所需的電視應用程式聲明android.software.live_tv功能標誌,必須滿足以下要求:

  • 設備實現應允許安裝和管理基於第三方TIF的輸入(第三方輸入)。
  • 設備實作可能會在基於TIF的預先安裝的輸入(安裝輸入)和第三方輸入之間提供視覺分離。
  • 裝置實現不應超過電視應用程式的單一導航操作的第三方輸入(即擴展電視應用程式中的第三方輸入清單)。

Android開源專案提供了滿足上述要求的電視應用程式的實作。

3.12.1.1.電子節目指南

如果設備實現支援TIF,則它們:

  • [C-1-1]必須顯示一個資訊和互動式覆蓋層,必須包括從TVContract.Programs欄位產生的電子程式指南(EPG)。
  • [C-1-2]關於頻道更改,裝置實作必須顯示目前播放程式的EPG資料。
  • [SR]強烈建議使用EPG以相等的突出顯示安裝的輸入和第三方輸入。 EPG不應顯示第三方輸入超過單一導覽操作,而不是EPG上的安裝輸入。
  • EPG應顯示所有已安裝的輸入和第三方輸入的資訊。
  • EPG可以在已安裝的輸入和第三方輸入之間提供視覺分離。
3.12.1.2.導航

如果設備實現支援TIF,則它們:

  • [C-1-1]必須允許透過Android Television裝置的輸入裝置(即遙控器,遠端控制應用程式或遊戲控制器)上的D-Pad,Back和Home Keys進行以下功能導航:

    • 變更電視頻道
    • 開放EPG
    • 配置和調諧到第三方基於TIF的輸入(如果支援這些輸入)
    • 開啟設定選單
  • 應將關鍵事件透過CEC傳遞給HDMI輸入。

3.12.1.3。電視輸入應用程式鏈接

Android電視設備實現應支援電視輸入應用程式鏈接,該鏈接允許所有輸入提供從當前活動到另一個活動的活動鏈接(即從實時編程到相關內容的鏈接)。電視應用程式應顯示電視輸入應用程式在提供時連結。

3.12.1.4。時移

如果設備實現支援TIF,則它們:

  • [SR]強烈建議支援時間變化,這使用戶可以暫停並恢復即時內容。
  • 如果時間轉移該程序,則應為使用者提供暫停並恢復目前播放程序的方法。
3.12.1.5。電視錄製

如果設備實現支援TIF,則它們:

  • [SR]強烈建議支持電視錄製。
  • 如果電視輸入支援錄製和程式記錄,則EPG可能會提供記錄程式的方法。

3.13.快速設定

Android提供了一個快速設定UI元件,可快速存取經常使用或緊急需要的操作。

如果設備實作包括快速設定UI元件,則它們:

  • [C-1-1]必須允許使用者從第三方應用程式中新增或刪除透過quicksettings API提供的圖塊。
  • [C-1-2]不得直接將第三方應用程式從第三方應用程式新增至快速設定。
  • [C-1-3]必須與系統提供的快速設定磁磚一起從第三方應用程式顯示所有使用者添加的磁磚。

3.14。媒體介面

如果裝置實作包括支援依賴MediaBrowserMediaSession的第三方應用程式的UI框架,則它們:

3.15。即時應用程式

設備實作必須滿足以下要求:

  • [C-0-1]即時應用程式只能授予具有android:protectionLevel設定為"ephemeral"權限。
  • [C-0-2]即時應用程式不得透過隱式意圖與已安裝的應用程式進行交互,除非以下一個是正確的:
    • 組件的意圖模式過濾器已公開並具有 CATEGORY_BROWSABLE
    • 操作是 ACTION_SEND、ACTION_SENDTO、ACTION_SEND_MULTIPLE 之一
    • 目標透過android:visibleToInstantApps明確公開
  • [C-0-3]即時應用程式不得與已安裝的應用程式明確交互,除非該元件透過Android:visibletoinstantapps暴露。
  • [C-0-4]除非Instant App明確連接到已安裝的應用程序,否則INSTALLED應用程式不得在裝置上看到有關即時應用程式的詳細資訊。

3.16。配套設備配對

Android包括對配對配對的支持,以更有效地管理與配套設備的關聯,並為應用程式提供了應用程式存取此功能的CompanionDeviceManager API。

如果設備實現支援配套設備配對功能,則:

4. 應用程式封裝相容性

設備實現:

  • [C-0-1] 必須能夠安裝和運行由官方 Android SDK中包含的「aapt」工具產生的 Android「.apk」檔案。
  • 由於上述要求可能具有挑戰性,因此建議使用設備實作來使用AOSP參考實現的軟體包管理SystemDevice實作。
  • [C-0-2]必須使用APK簽章方案V2JAR簽章支援驗證「 .APK」檔。
  • [C-0-3] 擴充功能.apkAndroid ManifestDalvik 字節碼或 RenderScript 字節碼格式時,不得以阻止這些檔案在其他相容裝置上正確安裝和運作的方式進行擴充。
  • [C-0-4]除了目前的「記錄的安裝程式」以外,該軟體包不得允許應用程式無需任何提示即可默默地卸載該應用程序,如SDK中的DELETE_PACKAGE權限所記錄的那樣。唯一的例外是處理PACKAGE_NEEDS_VERIFICATION意圖的系統套件驗證程式應用程式和處理ACTION_MANAGE_STORAGE意圖的儲存管理器應用程式。

設備實作不得從未知來源安裝應用程式包,除非要求安裝的應用程式符合以下所有要求:

  • 它必須宣告REQUEST_INSTALL_PACKAGES權限或將android:targetSdkVersion設定為24或更低。
  • 用戶必須已授予其安裝來自未知來源的應用程式的權限。

裝置實作必須具有處理android.settings.MANAGE_UNKNOWN_APP_SOURCES意圖的活動。他們應該提供一個用戶負擔能力,以授予/撤銷每個應用程式中未知來源安裝應用程式的許可,但可以選擇將其作為no-op實作並返回RESULT_CANCELED for startActivityForResult() ,如果裝置不希望使用者實作用戶有這個選擇。但是,即使在這種情況下,他們也應該向用戶表明為什麼沒有這樣的選擇。

5. 多媒體相容性

設備實現:

  • [C-0-1]必須支援媒體格式,編碼器,解碼器,檔案類型和容器格式在第5.1節中針對MediaCodecList聲明的每個編解碼器所定義的。
  • [C-0-2]必須聲明並報告編碼器的支持,並透過MediaCodecList向第三方應用程式提供的解碼器。
  • [C-0-3]必須能夠解碼並向第三方應用程式提供所有可以編碼的格式。這包括其編碼器產生的所有bitstreams和在其CamcorderProfile中報告的設定檔。

設備實現:

  • 應該以最小編解碼器延遲為目標,換句話說,它們
    • 不應消耗和儲存輸入緩衝區,並且僅在處理後返回輸入緩衝區。
    • 保留解碼緩衝區的時間不應超過標準(例如 SPS)指定的時間。
    • 保留編碼緩衝區的時間不應超過 GOP 結構所需的時間。

以下部分列出的所有編解碼器均作為 Android 開源專案的首選 Android 實作中的軟體實作提供。

請注意,Google 和開放手機聯盟均未聲明這些編解碼器不受第三方專利的影響。打算在硬體或軟體產品中使用此原始碼的人請注意,此程式碼的實現(包括在開源軟體或共享軟體中)可能需要相關專利持有者的專利許可。

5.1.媒體編解碼器

5.1.1.音訊編碼

請參閱5.1.3 中的更多詳細資訊。音訊編解碼器詳細資訊

如果裝置實作聲明android.hardware.microphone ,則必須支援以下音訊編碼:

  • [C-1-1] PCM/WAVE

5.1.2.音訊解碼

請參閱5.1.3 中的更多詳細資訊。音訊編解碼器詳細資訊

如果裝置實作聲明了對android.hardware.audio.output功能的支持,則它們:

  • [C-1-1] MPEG-4 AAC 設定檔 (AAC LC)
  • [C-1-2] MPEG-4 HE AAC 設定檔 (AAC+)
  • [C-1-3] MPEG-4 HE AACv2 設定檔(增強型 AAC+)
  • [C-1-4] AAC ELD(增強型低延遲 AAC)
  • [C-1-5] FLAC
  • [C-1-6] MP3
  • [C-1-7] MIDI
  • [C-1-8] 沃比斯
  • [C-1-9] PCM/WAVE
  • [C-1-10] 作品

如果裝置實作支援多通道流的AAC輸入緩衝區(即兩個以上的通道)透過android.media.MediaCodec API中的預設AAC音訊解碼器向PCM到PCM,則必須支援以下內容:

  • [C-2-1] 執行解碼時必須不進行縮混(例如,5.0 AAC 流必須解碼為 5 個 PCM 通道,5.1 AAC 流必須解碼為 6 個 PCM 通道)。
  • [C-2-2]動態範圍元資料必須在ISO/IEC 14496-3中的「動態範圍控制(DRC)」和android.media.MediaFormat DRC金鑰中定義,以配置與動態範圍相關的行為音訊解碼器。 AAC DRC鍵在API 21中引入,為:KEY_AAC_DRC_ATTENUATION_FACTOR,key_aac_drc_boost_factor,key_aac_drc_heavy_compression,key_aac_aac_drc_drc_trtarc_target_tararget_level_leac_aac_drc_drc_trtarc_target_tararget_level_lev

5.1.3.音頻編解碼器詳細信息

格式/編解碼器細節支援的文件類型/容器格式
MPEG-4 AAC設定文件
(AAC LC)
支援單聲道/立體聲/5.0/5.1 內容,標準取樣率為 8 至 48 kHz。
  • 3GPP (.3gp)
  • MPEG-4(.mp4、.m4a)
  • ADTS 原始 AAC(.aac,不支援 ADIF)
  • mpeg-ts(.ts,不可尋找)
MPEG-4 HE AAC 設定檔 (AAC+)支援單聲道/立體聲/5.0/5.1 內容,標準取樣率為 16 至 48 kHz。
MPEG-4 HE AACV2
Profile (enhanced AAC+)
支援單聲道/立體聲/5.0/5.1 內容,標準取樣率為 16 至 48 kHz。
AAC ELD (enhanced low delay AAC)支援單聲道/立體聲內容,標準取樣率為 16 至 48 kHz。
AMR-NB 8 kHz 時取樣率為 4.75 至 12.2 kbps 3GPP (.3gp)
AMR-WB 9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16 kHz
FLAC單聲道/立體聲(無多聲道)。 Sample rates up to 48 kHz (but up to 44.1 kHz is RECOMMENDED on devices with 44.1 kHz output, as the 48 to 44.1 kHz downsampler does not include a low-pass filter). 16-bit RECOMMENDED; 24 位元沒有套用抖動。限 FLAC (.flac)
MP3單聲道/立體聲 8-320Kbps 恆定 (CBR) 或可變位元速率 (VBR) MP3 (.mp3)
MIDI MIDI 類型 0 和 1。DLS 版本 1 和 2。XMF 和 Mobile XMF。支援鈴聲格式 RTTTL/RTX、OTA 和 iMelody
  • 類型 0 和 1(.mid、.xmf、.mxmf)
  • RTTTL/RTX(.rtttl、.rtx)
  • OTA (.ota)
  • iMelody (.imy)
沃爾比斯
  • 奧格 (.ogg)
  • Matroska (.mkv, Android 4.0+)
PCM/波16-bit linear PCM (rates up to limit of hardware). Devices MUST support sampling rates for raw PCM recording at 8000, 11025, 16000, and 44100 Hz frequencies.波形 (.wav)
作品Matroska (.mkv), Ogg(.ogg)

5.1.4. Image Encoding

See more details in 5.1.6. Image Codecs Details .

Device implementations MUST support encoding the following image encoding:

  • [C-0-1] JPEG
  • [C-0-2] PNG
  • [C-0-3] WebP

5.1.5。影像解碼

See more details in 5.1.6. Image Codecs Details .

Device implementations MUST support encoding the following image decoding:

  • [C-0-1] JPEG
  • [C-0-2] GIF
  • [C-0-3] PNG
  • [C-0-4] BMP
  • [C-0-5] WebP
  • [C-0-6] Raw

5.1.6。 Image Codecs Details

格式/編解碼器細節Supported File Types/Container Formats
JPEG基礎+漸進JPEG (.jpg)
動圖GIF (.gif)
巴布亞紐幾內亞PNG (.png)
骨形態發生蛋白點陣圖 (.bmp)
網路P WebP (.webp)
生的ARW (.arw)、CR2 (.cr2)、DNG (.dng)、NEF (.nef)、NRW (.nrw)、ORF (.orf)、PEF (.pef)、RAF (.raf)、RW2 ( .rw2)、SRW (.srw)

5.1.7.視訊編解碼器

  • For acceptable quality of web video streaming and video-conference services, device implementations SHOULD use a hardware VP8 codec that meets the requirements .

如果設備實作包括視訊解碼器或編碼器:

  • [C-1-1] Video codecs MUST support output and input bytebuffer sizes that accommodate the largest feasible compressed and uncompressed frame as dictated by the standard and configuration but also not overallocate.

  • [C-1-2] Video encoders and decoders MUST support YUV420 flexible color format (COLOR_FormatYUV420Flexible).

If device implementations advertise HDR profile support through Display.HdrCapabilities , they:

  • [C-2-1] 必須支援 HDR 靜態元資料解析和處理。

If device implementations advertise intra refresh support through FEATURE_IntraRefresh in the MediaCodecInfo.CodecCapabilities class, they:

  • [C-3-1]MUST support the refresh periods in the range of 10 - 60 frames and accurately operate within 20% of configured refresh period.

5.1.8.視訊編解碼器列表

格式/編解碼器細節Supported File Types/
容器格式
H.263
  • 3GPP (.3gp)
  • MPEG-4 (.mp4)
H.264AVC詳細資訊請參閱第 5.2 節第 5.3
  • 3GPP (.3gp)
  • MPEG-4 (.mp4)
  • MPEG-2 TS (.ts, AAC audio only, not seekable, Android 3.0+)
H.265 HEVC詳細資訊請參閱第 5.3 節MPEG-4 (.mp4)
MPEG-2主要簡介MPEG2-TS
MPEG-4 SP 3GPP (.3gp)
VP8詳細資訊請參閱第 5.2 節第 5.3
VP9詳細資訊請參閱第 5.3 節

5.2.視訊編碼

If device implementations support any video encoder and make it available to third-party apps, they:

  • SHOULD NOT be, over two sliding windows, more than ~15% over the bitrate between intraframe (I-frame) intervals.
  • SHOULD NOT be more than ~100% over the bitrate over a sliding window of 1 second.

If device implementations include an embedded screen display with the diagonal length of at least 2.5 inches or include a video output port or declare the support of a camera via the android.hardware.camera.any feature flag, they:

  • [C-1-1] MUST include the support of at least one of the VP8 or H.264 video encoders, and make it available for third-party applications.
  • SHOULD support both VP8 and H.264 video encoders, and make it available for third-party applications.

If device implementations support any of the H.264, VP8, VP9 or HEVC video encoders and make it available to third-party applications, they:

  • [C-2-1] MUST support dynamically configurable bitrates.
  • SHOULD support variable frame rates, where video encoder SHOULD determine instantaneous frame duration based on the timestamps of input buffers, and allocate its bit bucket based on that frame duration.

If device implementations support the MPEG-4 SP video encoder and make it available to third-party apps, they:

  • SHOULD support dynamically configurable bitrates for the supported encoder.

5.2.1. H.263

If device implementations support H.263 encoders and make it available to third-party apps, they:

  • [C-1-1] MUST support Baseline Profile Level 45.
  • SHOULD support dynamically configurable bitrates for the supported encoder.

5.2.2. H-264

If device implementations support H.264 codec, they:

  • [C-1-1] 必須支援基線設定檔層級 3。不過,對 ASO(任意切片排序)、FMO(彈性宏區塊排序)和 RS(冗餘切片)的支援是可選的。此外,為了保持與其他 Android 裝置的兼容性,建議編碼器不要將 ASO、FMO 和 RS 用於 Baseline Profile。
  • [C-1-2] 必須支援下表中的 SD(標清)視訊編碼設定檔。
  • 應支援主設定檔等級 4。
  • 應支援 HD(高清晰度)視訊編碼配置文件,如下表所示。

如果裝置實作報告透過媒體 API 支援 720p 或 1080p 解析度視訊的 H.264 編碼,則:

  • [C-2-1] 必須支援下表中的編碼設定檔。
標清(低品質)標清(高品質)高清720p高清1080p
視訊解析度320 x 240 像素720 x 480 像素1280 x 720 像素1920 x 1080 像素
視訊幀率20 幀/秒30 幀/秒30 幀/秒30 幀/秒
視訊比特率384Kbps 2Mbps 4Mbps 10Mbps

5.2.3. VP8

如果設備實作支援 VP8 編解碼器,則:

  • [C-1-1] MUST support the SD video encoding profiles.
  • 應支援以下 HD(高清晰度)視訊編碼設定檔。
  • SHOULD support writing Matroska WebM files.
  • SHOULD use a hardware VP8 codec that meets the WebM project RTC hardware coding requirements , to ensure acceptable quality of web video streaming and video-conference services.

如果設備實作報告透過媒體 API 支援 720p 或 1080p 解析度視訊的 VP8 編碼,則:

  • [C-2-1] 必須支援下表中的編碼設定檔。
標清(低品質)標清(高品質)高清720p高清1080p
視訊解析度320 x 180 像素640 x 360 像素1280 x 720 像素1920 x 1080 像素
視訊幀率30 幀/秒30 幀/秒30 幀/秒30 幀/秒
視訊比特率800Kbps 2Mbps 4Mbps 10Mbps

5.2.4. VP9

如果設備實作支援 VP9 編解碼器,則:

  • SHOULD support writing Matroska WebM files.

5.3.視訊解碼

如果設備實作支援 VP8、VP9、H.264 或 H.265 編解碼器,則:

  • [C-1-1] 必須支援透過同一流中的標準Android API 對所有VP8、VP9、H.264 和H.265 編解碼器進行即時動態視訊解析度和幀速率切換,且最高可達支援的最大解析度由設備上的每個編解碼器。

If device implementations declare support for the Dolby Vision decoder through HDR_TYPE_DOLBY_VISION , they:

  • [C-2-1] MUST provide a Dolby Vision-capable extractor.
  • [C-2-2] MUST properly display Dolby Vision content on the device screen or on a standard video output port (eg, HDMI).
  • [C-2-3] MUST set the track index of backward-compatible base-layer(s) (if present) to be the same as the combined Dolby Vision layer's track index.

5.3.1. MPEG-2

如果裝置實作支援 MPEG-2 解碼器,則它們:

  • [C-1-1] 必須支援主要設定檔高等級。

5.3.2. H.263

如果設備實作支援 H.263 解碼器,則:

  • [C-1-1] MUST support Baseline Profile Level 30 and Level 45.

5.3.3. MPEG-4

如果裝置實作具有 MPEG-4 解碼器,則:

  • [C-1-1] 必須支援簡單設定檔等級 3。

5.3.4. H.264

如果設備實作支援 H.264 解碼器,則:

  • [C-1-1] 必須支援主設定檔等級 3.1 和基線設定檔。對 ASO(任意切片排序)、FMO(靈活宏塊排序)和 RS(冗餘切片)的支援是可選的。
  • [C-1-2] 必須能夠解碼具有下表中列出的 SD(標清)設定檔並使用 Baseline Profile 和 Main Profile Level 3.1(包括 720p30)編碼的影片。
  • 應能夠解碼具有 HD(高清晰度)配置文件的視頻,如下表所示。

If the height that is reported by the Display.getSupportedModes() method is equal or greater than the video resolution, device implementations:

  • [C-2-1] MUST support the HD 720p video encoding profiles in the following table.
  • [C-2-2] MUST support the HD 1080p video encoding profiles in the following table.
標清(低品質)標清(高品質)高清720p高清1080p
視訊解析度320 x 240 像素720 x 480 像素1280 x 720 像素1920 x 1080 像素
視訊幀率30 幀/秒30 幀/秒60 幀/秒30 fps(60 fps電視
視訊比特率800Kbps 2Mbps 8Mbps 20Mbps

5.3.5。 H.265 (HEVC)

如果設備實作支援 H.265 編解碼器,則:

  • [C-1-1] 必須支援主設定檔第 3 級主層和 SD 視訊解碼設定文件,如下表所示。
  • 應支援下表所示的高清解碼設定檔。
  • [C-1-2] 如果有硬體解碼器,則必須支援下表所示的高清解碼設定檔。

If the height that is reported by the Display.getSupportedModes() method is equal to or greater than the video resolution, then:

  • [C-2-1] 設備實作必須至少支援 720、1080 和 UHD 設定檔的 H.265 或 VP9 解碼之一。
標清(低品質)標清(高品質)高清720p高清1080p超高畫質
視訊解析度352 x 288 像素720 x 480 像素1280 x 720 像素1920 x 1080 像素3840 x 2160 像素
視訊幀率30 幀/秒30 幀/秒30 幀/秒30/60 fps(60 fps電視,採用 H.265 硬體解碼 60 幀/秒
視訊比特率600Kbps 1.6Mbps 4Mbps 5Mbps 20Mbps

5.3.6。 VP8

如果設備實作支援 VP8 編解碼器,則:

  • [C-1-1] 必須支援下表中的 SD 解碼設定檔。
  • 應使用符合 要求的硬體 VP8 編解碼器。
  • 應支援下表中的高清解碼設定檔。

If the height as reported by the Display.getSupportedModes() method is equal or greater than the video resolution, then:

  • [C-2-1] 設備實作必須支援下表中的 720p 設定檔。
  • [C-2-2] 設備實作必須支援下表中的 1080p 設定檔。
標清(低品質)標清(高品質)高清720p高清1080p
視訊解析度320 x 180 像素640 x 360 像素1280 x 720 像素1920 x 1080 像素
視訊幀率30 幀/秒30 幀/秒30 fps(60 fps電視 30(60 fps電視
視訊比特率800Kbps 2Mbps 8Mbps 20Mbps

5.3.7. VP9

如果設備實作支援 VP9 編解碼器,則:

  • [C-1-1] 必須支援下表所示的標清視訊解碼設定檔。
  • 應支援下表所示的高清解碼設定檔。

如果設備實作支援 VP9 編解碼器和硬體解碼器:

  • [C-2-2] MUST support the HD decoding profiles as indicated in the following table.

If the height that is reported by the Display.getSupportedModes() method is equal to or greater than the video resolution, then:

  • [C-3-1] 設備實作必須至少支援 720、1080 和 UHD 設定檔的 VP9 或 H.265 解碼之一。
標清(低品質)標清(高品質)高清720p高清1080p超高畫質
視訊解析度320 x 180 像素640 x 360 像素1280 x 720 像素1920 x 1080 像素3840 x 2160 像素
視訊幀率30 幀/秒30 幀/秒30 幀/秒30 fps(60 fps電視,附 VP9 硬體解碼 60 幀/秒
視訊比特率600Kbps 1.6Mbps 4Mbps 5Mbps 20Mbps

5.4.聲音錄製

雖然本節概述的一些要求自 Android 4.3 起被列為“應該”,但未來版本的兼容性定義計劃將這些要求更改為“必須”。 Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements that are listed as SHOULD, or they will not be able to attain Android compatibility when upgraded to the future version.

5.4.1. Raw Audio Capture

If device implementations declare android.hardware.microphone , they:

  • [C-1-1] MUST allow capture of raw audio content with the following characteristics:

  • Format : Linear PCM, 16-bit

  • Sampling rates : 8000, 11025, 16000, 44100 Hz
  • Channels : Mono

  • [C-1-2] MUST capture at above sample rates without up-sampling.

  • [C-1-3] MUST include an appropriate anti-aliasing filter when the sample rates given above are captured with down-sampling.
  • SHOULD allow AM radio and DVD quality capture of raw audio content, which means the following characteristics:

  • Format : Linear PCM, 16-bit

  • Sampling rates : 22050, 48000 Hz
  • Channels : Stereo

If device implementations allow AM radio and DVD quality capture of raw audio content, they:

  • [C-2-1] MUST capture without up-sampling at any ratio higher than 16000:22050 or 44100:48000.
  • [C-2-2] 必須為任何上取樣或下取樣包含適當的抗混疊濾波器。

5.4.2. Capture for Voice Recognition

If device implementations declare android.hardware.microphone , they:

  • [C-1-1] MUST capture android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION audio source at one of the sampling rates, 44100 and 48000.
  • [C-1-2] MUST, by default, disable any noise reduction audio processing when recording an audio stream from the AudioSource.VOICE_RECOGNITION audio source.
  • [C-1-3] MUST, by default, disable any automatic gain control when recording an audio stream from the AudioSource.VOICE_RECOGNITION audio source.
  • SHOULD record the voice recognition audio stream with approximately flat amplitude versus frequency characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
  • SHOULD record the voice recognition audio stream with input sensitivity set such that a 90 dB sound power level (SPL) source at 1000 Hz yields RMS of 2500 for 16-bit samples.
  • 應記錄語音辨識音訊串流,以便 PCM 幅度水平線性追蹤輸入 SPL 在 -18 dB 至 +12 dB(麥克風處的 90 dB SPL)至少 30 dB 範圍內的變化。
  • SHOULD record the voice recognition audio stream with total harmonic distortion (THD) less than 1% for 1 kHz at 90 dB SPL input level at the microphone.

If device implementations declare android.hardware.microphone and noise suppression (reduction) technologies tuned for speech recognition, they:

  • [C-2-1] MUST allow this audio affect to be controllable with the android.media.audiofx.NoiseSuppressor API.
  • [C-2-2] MUST uniquely identfiy each noise suppression technology implementation via the AudioEffect.Descriptor.uuid field.

5.4.3. Capture for Rerouting of Playback

The android.media.MediaRecorder.AudioSource class includes the REMOTE_SUBMIX audio source.

If device implementations declare both android.hardware.audio.output and android.hardware.microphone , they:

  • [C-1-1] MUST properly implement the REMOTE_SUBMIX audio source so that when an application uses the android.media.AudioRecord API to record from this audio source, it captures a mix of all audio streams except for the following:

    • AudioManager.STREAM_RING
    • AudioManager.STREAM_ALARM
    • AudioManager.STREAM_NOTIFICATION

5.5.音訊播放

Android includes the support to allow apps to playback audio through the audio output peripheral as defined in section 7.8.2.

5.5.1. Raw Audio Playback

If device implementations declare android.hardware.audio.output , they:

  • [C-1-1] MUST allow playback of raw audio content with the following characteristics:

    • Format : Linear PCM, 16-bit
    • Sampling rates : 8000, 11025, 16000, 22050, 32000, 44100
    • Channels : Mono, Stereo
  • SHOULD allow playback of raw audio content with the following characteristics:

    • Sampling rates : 24000, 48000

5.5.2.音訊效果

Android provides an API for audio effects for device implementations.

If device implementations declare the feature android.hardware.audio.output , they:

  • [C-1-1] MUST support the EFFECT_TYPE_EQUALIZER and EFFECT_TYPE_LOUDNESS_ENHANCER implementations controllable through the AudioEffect subclasses Equalizer , LoudnessEnhancer .
  • [C-1-2] MUST support the visualizer API implementation, controllable through the Visualizer class.
  • SHOULD support the EFFECT_TYPE_BASS_BOOST , EFFECT_TYPE_ENV_REVERB , EFFECT_TYPE_PRESET_REVERB , and EFFECT_TYPE_VIRTUALIZER implementations controllable through the AudioEffect sub-classes BassBoost , EnvironmentalReverb , PresetReverb , and Virtualizer .

5.5.3.音訊輸出音量

汽車設備實現:

  • SHOULD allow adjusting audio volume separately per each audio stream using the content type or usage as defined by AudioAttributes and car audio usage as publicly defined in android.car.CarAudioManager .

5.6.音訊延遲

Audio latency is the time delay as an audio signal passes through a system. Many classes of applications rely on short latencies, to achieve real-time sound effects.

就本節而言,使用以下定義:

  • output latency . The interval between when an application writes a frame of PCM-coded data and when the corresponding sound is presented to environment at an on-device transducer or signal leaves the device via a port and can be observed externally.
  • cold output latency . The output latency for the first frame, when the audio output system has been idle and powered down prior to the request.
  • continuous output latency . The output latency for subsequent frames, after the device is playing audio.
  • input latency . The interval between when a sound is presented by environment to device at an on-device transducer or signal enters the device via a port and when an application reads the corresponding frame of PCM-coded data.
  • lost input . The initial portion of an input signal that is unusable or unavailable.
  • cold input latency . The sum of lost input time and the input latency for the first frame, when the audio input system has been idle and powered down prior to the request.
  • continuous input latency . The input latency for subsequent frames, while the device is capturing audio.
  • cold output jitter . The variability among separate measurements of cold output latency values.
  • cold input jitter . The variability among separate measurements of cold input latency values.
  • continuous round-trip latency . The sum of continuous input latency plus continuous output latency plus one buffer period. The buffer period allows time for the app to process the signal and time for the app to mitigate phase difference between input and output streams.
  • OpenSL ES PCM buffer queue API . The set of PCM-related OpenSL ES APIs within Android NDK .
  • AAudio native audio API . The set of AAudio APIs within Android NDK .

If device implementations declare android.hardware.audio.output they are STRONGLY RECOMMENDED to meet or exceed the following requirements:

  • [SR] Cold output latency of 100 milliseconds or less
  • [SR] Continuous output latency of 45 milliseconds or less
  • [SR] Minimize the cold output jitter

If device implementations meet the above requirements after any initial calibration when using the OpenSL ES PCM buffer queue API, for continuous output latency and cold output latency over at least one supported audio output device, they are:

  • [SR] STRONGLY RECOMMENDED to report low latency audio by declaring android.hardware.audio.low_latency feature flag.
  • [SR] STRONGLY RECOMMENDED to also meet the requirements for low-latency audio via the AAudio API.

If device implementations do not meet the requirements for low-latency audio via the OpenSL ES PCM buffer queue API, they:

  • [C-1-1] MUST NOT report support for low-latency audio.

If device implementations include android.hardware.microphone , they are STRONGLY RECOMMENDED to meet these input audio requirements:

  • [SR] Cold input latency of 100 milliseconds or less
  • [SR] Continuous input latency of 30 milliseconds or less
  • [SR] Continuous round-trip latency of 50 milliseconds or less
  • [SR] Minimize the cold input jitter

5.7.網路協定

Device implementations MUST support the media network protocols for audio and video playback as specified in the Android SDK documentation.

If device implementations include an audio or a video decoder, they:

  • [C-1-1] MUST support all required codecs and container formats in section 5.1 over HTTP(S).

  • [C-1-2] MUST support the media segment formats shown in the Media Segmant Formats table below over HTTP Live Streaming draft protocol, Version 7 .

  • [C-1-3] MUST support the following RTP audio video profile and related codecs in the RTSP table below. For exceptions please see the table footnotes in section 5.1 .

Media Segment Formats

Segment formats參考)所需的編解碼器支持
MPEG-2 Transport Stream ISO 13818 Video codecs:
  • H264 AVC
  • MPEG-4 SP
  • MPEG-2
See section 5.1.3 for details on H264 AVC, MPEG2-4 SP,
and MPEG-2.

Audio codecs:

  • 亞克力
See section 5.1.1 for details on AAC and its variants.
AAC with ADTS framing and ID3 tags ISO 13818-7 See section 5.1.1 for details on AAC and its variants
網路VTT網路VTT

RTSP(RTP、SDP)

個人資料名稱參考)所需的編解碼器支持
H264 AVC RFC 6184 See section 5.1.3 for details on H264 AVC
MP4A-LATM RFC 6416 See section 5.1.1 for details on AAC and its variants
H263-1998 RFC 3551
RFC 4629
RFC 2190
See section 5.1.3 for details on H263
H263-2000 RFC 4629 See section 5.1.3 for details on H263
抗微生物藥物抗藥性RFC 4867 See section 5.1.1 for details on AMR-NB
AMR-WB RFC 4867 See section 5.1.1 for details on AMR-WB
MP4V-ES RFC 6416 See section 5.1.3 for details on MPEG-4 SP
mpeg4-generic RFC 3640 See section 5.1.1 for details on AAC and its variants
MP2T RFC 2250 See MPEG-2 Transport Stream underneath HTTP Live Streaming for details

5.8.安全媒體

If device implementations support secure video output and are capable of supporting secure surfaces, they:

  • [C-1-1] MUST declare support for Display.FLAG_SECURE .

If device implementations declare support for Display.FLAG_SECURE and support wireless display protocol, they:

  • [C-2-1] 對於透過 Miracast 等無線協定連接的顯示器,必須使用 HDCP 2.x 或更高版本等加密機制來保護連結的安全。

If device implementations declare support for Display.FLAG_SECURE and support wired external display, they:

  • [C-3-1] MUST support HDCP 1.2 or higher for all wired external displays.

5.9.樂器數位介面 (MIDI)

If device implementations report support for feature android.software.midi via the android.content.pm.PackageManager class, they:

  • [C-1-1] MUST support MIDI over all MIDI-capable hardware transports for which they provide generic non-MIDI connectivity, where such transports are:

  • [C-1-2] 必須支援應用間 MIDI 軟體傳輸(虛擬 MIDI 裝置)

5.10.專業音響

If device implementations report support for feature android.hardware.audio.pro via the android.content.pm.PackageManager class, they:

  • [C-1-1] MUST report support for feature android.hardware.audio.low_latency .
  • [C-1-2] MUST have the continuous round-trip audio latency, as defined in section 5.6 Audio Latency , MUST be 20 milliseconds or less and SHOULD be 10 milliseconds or less over at least one supported path.
  • [C-1-3] MUST include a USB port(s) supporting USB host mode and USB peripheral mode.
  • [C-1-4] MUST report support for feature android.software.midi .
  • [C-1-5] MUST meet latencies and USB audio requirements using the OpenSL ES PCM buffer queue API.
  • [SR] Are STRONGLY RECOMMENDED to provide a consistent level of CPU performance while audio is active and CPU load is varying. This should be tested using SimpleSynth commit 1bd6391 . The SimpleSynth app needs to be run with below parameters and achieve zero underruns after 10 minutes:
    • Work cycles: 200,000
    • Variable load: ON (this will switch between 100% and 10% of the work cycles value every 2 seconds and is designed to test CPU governor behavior)
    • Stabilized load: OFF
  • SHOULD minimize audio clock inaccuracy and drift relative to standard time.
  • SHOULD minimize audio clock drift relative to the CPU CLOCK_MONOTONIC when both are active.
  • SHOULD minimize audio latency over on-device transducers.
  • SHOULD minimize audio latency over USB digital audio.
  • 應記錄所有路徑上的音訊延遲測量結果。
  • SHOULD minimize jitter in audio buffer completion callback entry times, as this affects usable percentage of full CPU bandwidth by the callback.
  • SHOULD provide zero audio underruns (output) or overruns (input) under normal use at reported latency.
  • 應提供零通道間延遲差異。
  • SHOULD minimize MIDI mean latency over all transports.
  • SHOULD minimize MIDI latency variability under load (jitter) over all transports.
  • 應在所有傳輸上提供準確的 MIDI 時間戳。
  • 應盡量減少設備上感測器上的音頻訊號噪聲,包括冷啟動後的一段時間。
  • SHOULD provide zero audio clock difference between the input and output sides of corresponding end-points, when both are active. Examples of corresponding end-points include the on-device microphone and speaker, or the audio jack input and output.
  • SHOULD handle audio buffer completion callbacks for the input and output sides of corresponding end-points on the same thread when both are active, and enter the output callback immediately after the return from the input callback. Or if it is not feasible to handle the callbacks on the same thread, then enter the output callback shortly after entering the input callback to permit the application to have a consistent timing of the input and output sides.
  • SHOULD minimize the phase difference between HAL audio buffering for the input and output sides of corresponding end-points.
  • SHOULD minimize touch latency.
  • SHOULD minimize touch latency variability under load (jitter).

If device implementations meet all of the above requirements, they:

If device implementations meet the requirements via the OpenSL ES PCM buffer queue API, they:

  • [SR] STRONGLY RECOMMENDED to also meet the same requirements via the AAudio API.

If device implementations include a 4 conductor 3.5mm audio jack, they:

如果裝置實現省略 4 導體 3.5mm 音訊插孔並包含支援 USB 主機模式的 USB 端口,則:

  • [C-3-1] MUST implement the USB audio class.
  • [C-3-2] MUST have a continuous round-trip audio latency of 20 milliseconds or less over the USB host mode port using USB audio class.
  • The continuous round-trip audio latency SHOULD be 10 milliseconds or less over the USB host mode port using USB audio class.

如果設備實現包含 HDMI 端口,則:

  • [C-4-1] MUST support output in stereo and eight channels at 20-bit or 24-bit depth and 192 kHz without bit-depth loss or resampling.

5.11.捕獲未處理的

Android includes support for recording of unprocessed audio via the android.media.MediaRecorder.AudioSource.UNPROCESSED audio source. In OpenSL ES, it can be accessed with the record preset SL_ANDROID_RECORDING_PRESET_UNPROCESSED .

If device implementations intent to support unprocessed audio source and make it available to third-party apps, they:

  • [C-1-1] MUST report the support through the android.media.AudioManager property PROPERTY_SUPPORT_AUDIO_SOURCE_UNPROCESSED .

  • [C-1-2] MUST exhibit approximately flat amplitude-versus-frequency characteristics in the mid-frequency range: specifically ±10dB from 100 Hz to 7000 Hz for each and every microphone used to record the unprocessed audio source.

  • [C-1-3] MUST exhibit amplitude levels in the low frequency range: specifically from ±20 dB from 5 Hz to 100 Hz compared to the mid-frequency range for each and every microphone used to record the unprocessed audio source.

  • [C-1-4] MUST exhibit amplitude levels in the high frequency range: specifically from ±30 dB from 7000 Hz to 22 KHz compared to the mid-frequency range for each and every microphone used to record the unprocessed audio source.

  • [C-1-5] MUST set audio input sensitivity such that a 1000 Hz sinusoidal tone source played at 94 dB Sound Pressure Level (SPL) yields a response with RMS of 520 for 16 bit-samples (or -36 dB Full Scale for floating point/double precision samples) for each and every microphone used to record the unprocessed audio source.

  • [C-1-6] MUST have a signal-to-noise ratio (SNR) at 60 dB or higher for each and every microphone used to record the unprocessed audio source. (whereas the SNR is measured as the difference between 94 dB SPL and equivalent SPL of self noise, A-weighted).

  • [C-1-7] 對於用於錄製未處理音訊來源的每個麥克風,在 90 dB SPL 輸入電平、1 kHZ 時,總諧波失真 (THD) 必須小於 1%。

  • MUST not have any other signal processing (eg Automatic Gain Control, High Pass Filter, or Echo cancellation) in the path other than a level multiplier to bring the level to desired range.換句話說:

  • [C-1-8] If any signal processing is present in the architecture for any reason, it MUST be disabled and effectively introduce zero delay or extra latency to the signal path.
  • [C-1-9] The level multiplier, while allowed to be on the path, MUST NOT introduce delay or latency to the signal path.

All SPL measurements are made directly next to the microphone under test. For multiple microphone configurations, these requirements apply to each microphone.

If device implementations declare android.hardware.microphone but do not support unprocessed audio source, they:

  • [C-2-1] MUST return null for the AudioManager.getProperty(PROPERTY_SUPPORT_AUDIO_SOURCE_UNPROCESSED) API method, to properly indicate the lack of support.
  • [SR] are still STRONGLY RECOMMENDED to satisfy as many of the requirements for the signal path for the unprocessed recording source.

6. 開發者工具和選項相容性

6.1.開發者工具

設備實現:

  • [C-0-1] MUST support the Android Developer Tools provided in the Android SDK.
  • Android Debug Bridge (adb)

    • [C-0-2] MUST support all adb functions as documented in the Android SDK including dumpsys .
    • [C-0-3] MUST NOT alter the format or the contents of device system events (batterystats , diskstats, fingerprint, graphicsstats, netstats, notification, procstats) logged via dumpsys.
    • [C-0-4] MUST have the device-side adb daemon be inactive by default and there MUST be a user-accessible mechanism to turn on the Android Debug Bridge.
    • [C-0-5] MUST support secure adb. Android includes support for secure adb. Secure adb enables adb on known authenticated hosts.
    • [C-0-6] MUST provide a mechanism allowing adb to be connected from a host machine.例如:

      • Device implementations without a USB port supporting peripheral mode MUST implement adb via local-area network (such as Ethernet or Wi-Fi).
      • MUST provide drivers for Windows 7, 9 and 10, allowing developers to connect to the device using the adb protocol.
  • Dalvik Debug Monitor Service (ddms)

    • [C-0-7] MUST support all ddms features as documented in the Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default, but MUST be supported whenever the user has activated the Android Debug Bridge, as above.
    • [C-0-8] MUST include the Monkey framework and make it available for applications to use.
  • SysTrace
    • [C-0-9] MUST support systrace tool as documented in the Android SDK. Systrace must be inactive by default and there MUST be a user-accessible mechanism to turn on Systrace.

6.2.開發者選項

Android 支援開發人員配置應用程式開發相關的設定。

設備實現必須為開發者選項提供一致的體驗,它們:

  • [C-0-1] MUST honor the android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application development-related settings. The upstream Android implementation hides the Developer Options menu by default and enables users to launch Developer Options after pressing seven (7) times on the Settings > About Device > Build Number menu item.
  • [C-0-2] MUST hide Developer Options by default and MUST provide a mechanism to enable Developer Options without the need for any special allowlisting.
  • MAY temporarily limit access to the Developer Options menu, by visually hiding or disabling the menu, to prevent distraction for scenarios where the safety of the user is of concern.

7. 硬體相容性

如果設備包含特定硬體元件,且該元件具有供第三方開發人員使用的對應 API:

  • [C-0-1] The device implementation MUST implement that API as described in the Android SDK documentation.

如果 SDK 中的 API 與指定為可選的硬體元件交互,且裝置實作不擁有該元件:

  • [C-0-2] Complete class definitions (as documented by the SDK) for the component APIs MUST still be presented.
  • [C-0-3] The API's behaviors MUST be implemented as no-ops in some reasonable fashion.
  • [C-0-4] API methods MUST return null values where permitted by the SDK documentation.
  • [C-0-5] API methods MUST return no-op implementations of classes where null values are not permitted by the SDK documentation.
  • [C-0-6] API methods MUST NOT throw exceptions not documented by the SDK documentation.
  • [C-0-7] Device implementations MUST consistently report accurate hardware configuration information via the getSystemAvailableFeatures() and hasSystemFeature(String) methods on the android.content.pm.PackageManager class for the same build fingerprint.

A typical example of a scenario where these requirements apply is the telephony API: Even on non-phone devices, these APIs must be implemented as reasonable no-ops.

7.1.顯示和圖形

Android includes facilities that automatically adjust application assets and UI layouts appropriately for the device to ensure that third-party applications run well on a variety of hardware configurations .設備必須正確實作這些 API 和行為,如本節所述。

本節要求引用的單位定義如下:

  • physical diagonal size .顯示器照明部分的兩個相對角落之間的距離(以英吋為單位)。
  • dots per inch (dpi) . The number of pixels encompassed by a linear horizontal or vertical span of 1”. Where dpi values are listed, both horizontal and vertical dpi must fall within the range.
  • 長寬比。螢幕較長尺寸與較短尺寸的像素之比。 For example, a display of 480x854 pixels would be 854/480 = 1.779, or roughly “16:9”.
  • 與密度無關的像素 (dp) 。 The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels = dps * (density/160).

7.1.1.螢幕配置

7.1.1.1.螢幕尺寸

The Android UI framework supports a variety of different logical screen layout sizes, and allows applications to query the current configuration's screen layout size via Configuration.screenLayout with the SCREENLAYOUT_SIZE_MASK and Configuration.smallestScreenWidthDp .

  • [C-0-1] Device implementations MUST report the correct layout size for the Configuration.screenLayout as defined in the Android SDK documentation. Specifically, device implementations MUST report the correct logical density-independent pixel (dp) screen dimensions as below:

    • Devices with the Configuration.uiMode set as any value other than UI_MODE_TYPE_WATCH, and reporting a small size for the Configuration.screenLayout , MUST have at least 426 dp x 320 dp.
    • Devices reporting a normal size for the Configuration.screenLayout , MUST have at least 480 dp x 320 dp.
    • Devices reporting a large size for the Configuration.screenLayout , MUST have at least 640 dp x 480 dp.
    • Devices reporting a xlarge size for the Configuration.screenLayout , MUST have at least 960 dp x 720 dp.
  • [C-0-2] Device implementations MUST correctly honor applications' stated support for screen sizes through the < supports-screens > attribute in the AndroidManifest.xml, as described in the Android SDK documentation.

7.1.1.2.螢幕縱橫比

While there is no restriction to the screen aspect ratio value of the physical screen display, the screen aspect ratio of the logical display that third-party apps are rendered within, as can be derived from the height and width values reported through the view.Display APIs and Configuration API, MUST meet the following requirements:

  • [C-0-1] Device implementations with the Configuration.uiMode set as UI_MODE_TYPE_NORMAL MUST have an aspect ratio value between 1.3333 (4:3) and 1.86 (roughly 16:9), unless the app can be deemed as ready to be stretched longer by meeting one of the following conditions:

    • The app has declared that it supports a larger screen aspect ratio through the android.max_aspect metadata value.
    • The app declares it is resizeable via the android:resizeableActivity attribute.
    • The app is targeting API level 26 or higher and does not declare a android:MaxAspectRatio that would restrict the allowed aspect ratio.
  • [C-0-2] Device implementations with the Configuration.uiMode set as UI_MODE_TYPE_WATCH MUST have an aspect ratio value set as 1.0 (1:1).

7.1.1.3。螢幕密度

Android UI 框架定義了一組標準邏輯密度來幫助應用程式開發人員定位應用程式資源。

  • [C-0-1] By default, device implementations MUST report only one of the following logical Android framework densities through the DENSITY_DEVICE_STABLE API and this value MUST NOT change at any time; however, the device MAY report a different arbitrary density according to the display configuration changes made by the user (for example, display size) set after initial boot.

    • 120 dpi(LDPI)
    • 160 dpi (mdpi)
    • 213 dpi(電視dpi)
    • 240 dpi(高清)
    • 260 dpi (260dpi)
    • 280dpi (280dpi)
    • 300 dpi (300dpi)
    • 320 dpi(xhdpi)
    • 340 dpi (340dpi)
    • 360dpi (360dpi)
    • 400dpi (400dpi)
    • 420 dpi (420dpi)
    • 480 dpi (xxhdpi)
    • 560dpi(560dpi)
    • 640 dpi (xxxhdpi)
  • 裝置實現應該定義在數值上最接近螢幕物理密度的標準 Android 框架密度,除非該邏輯密度將報告的螢幕尺寸推至支援的最小值以下。如果在數字上最接近物理密度的標準 Android 框架密度導致螢幕尺寸小於支援的最小相容螢幕尺寸(320 dp 寬度),則裝置實現應該報告下一個最低的標準 Android 框架密度。

If there is an affordance to change the display size of the device:

  • [C-1-1] The display size MUST NOT be scaled any larger than 1.5 times the native density or produce an effective minimum screen dimension smaller than 320dp (equivalent to resource qualifier sw320dp), whichever comes first.
  • [C-1-2] Display size MUST NOT be scaled any smaller than 0.85 times the native density.
  • 為了確保良好的可用性和一致的字體大小,建議提供以下本機顯示選項縮放(同時遵守上述指定的限制)
  • 小:0.85x
  • 預設值:1x(本機顯示比例)
  • 大:1.15x
  • 更大:1.3x
  • 最大1.45倍

7.1.2.顯示指標

如果設備實作包括螢幕或視訊輸出,則它們:

如果裝置實作不包括嵌入式螢幕或視訊輸出,則:

  • [C-2-1] MUST report reasonable values for all display metrics defined in the android.util.DisplayMetrics API for the emulated default view.Display .

7.1.3.螢幕方向

設備實現:

  • [C-0-1] MUST report which screen orientations they support ( android.hardware.screen.portrait and/or android.hardware.screen.landscape ) and MUST report at least one supported orientation. For example, a device with a fixed orientation landscape screen, such as a television or laptop, SHOULD only report android.hardware.screen.landscape .
  • [C-0-2] MUST report the correct value for the device's current orientation, whenever queried via the android.content.res.Configuration.orientation , android.view.Display.getOrientation() , or other APIs.

如果設備實現支援兩種螢幕方向,則:

  • [C-1-1] 必須支援應用程式動態定向為縱向或橫向螢幕方向。也就是說,設備必須尊重應用程式對特定螢幕方向的請求。
  • [C-1-2] 更改方向時不得更改報告的螢幕尺寸或密度。
  • 可以選擇縱向或橫向作為預設方向。

7.1.4. 2D 和 3D 圖形加速

7.1.4.1 OpenGL ES

設備實現:

  • [C-0-1] MUST correctly identify the supported OpenGL ES versions (1.1, 2.0, 3.0, 3.1, 3.2) through the managed APIs (such as via the GLES10.getString() method) and the native APIs.
  • [C-0-2] 必須支援他們確定要支援的每個 OpenGL ES 版本的所有對應託管 API 和本機 API。

如果設備實作包括螢幕或視訊輸出,則它們:

  • [C-1-1] MUST support both OpenGL ES 1.0 and 2.0, as embodied and detailed in the Android SDK documentation .
  • [SR] are STRONGLY RECOMMENDED to support OpenGL ES 3.0.
  • SHOULD support OpenGL ES 3.1 or 3.2.

如果裝置實作支援任何 OpenGL ES 版本,則它們:

  • [C-2-1] 必須透過 OpenGL ES 託管 API 和本機 API 報告它們已實現的任何其他 OpenGL ES 擴展,反之不得報告它們不支援的擴展字串。
  • [C-2-2] MUST support the EGL_KHR_image , EGL_KHR_image_base , EGL_ANDROID_image_native_buffer , EGL_ANDROID_get_native_client_buffer , EGL_KHR_wait_sync , EGL_KHR_get_all_proc_addresses , EGL_ANDROID_presentation_time , EGL_KHR_swap_buffers_with_damage and EGL_ANDROID_recordable extensions.
  • [SR] are STRONGLY RECOMMENDED to support EGL_KHR_partial_update.
  • SHOULD accurately report via the getString() method, any texture compression format that they support, which is typically vendor-specific.

如果裝置實作聲明支援 OpenGL ES 3.0、3.1 或 3.2,則:

  • [C-3-1] 除了 libGLESv2.so 函式庫中的 OpenGL ES 2.0 函數符號之外,還必須匯出這些版本的對應函數符號。

如果裝置實作支援 OpenGL ES 3.2,則:

  • [C-4-1] 必須完整支援 OpenGL ES Android 擴充包。

如果裝置實作完全支援 OpenGL ES Android 擴充包,則:

  • [C-5-1] MUST identify the support through the android.hardware.opengles.aep feature flag.

If device implementations expose support for the EGL_KHR_mutable_render_buffer extension, they:

  • [C-6-1] MUST also support the EGL_ANDROID_front_buffer_auto_refresh extension.
7.1.4.2 伏爾甘

Android 支援Vulkan ,這是一種用於高效能 3D 圖形的低開銷、跨平台 API。

If device implementations support OpenGL ES 3.0 or 3.1, they:

  • [SR] Are STRONGLY RECOMMENDED to include support for Vulkan 1.0 .

如果設備實作包括螢幕或視訊輸出,則它們:

  • SHOULD include support for Vulkan 1.0.

Device implementations, if including support for Vulkan 1.0:

  • [C-1-1] MUST report the correct integer value with the android.hardware.vulkan.level and android.hardware.vulkan.version feature flags.
  • [C-1-2] MUST enumerate, at least one VkPhysicalDevice for the Vulkan native API vkEnumeratePhysicalDevices() .
  • [C-1-3] MUST fully implement the Vulkan 1.0 APIs for each enumerated VkPhysicalDevice .
  • [C-1-4] MUST enumerate layers, contained in native libraries named as libVkLayer*.so in the application package's native library directory, through the Vulkan native APIs vkEnumerateInstanceLayerProperties() and vkEnumerateDeviceLayerProperties() .
  • [C-1-5] MUST NOT enumerate layers provided by libraries outside of the application package, or provide other ways of tracing or intercepting the Vulkan API, unless the application has the android:debuggable attribute set as true .
  • [C-1-6] 必須報告它們透過 Vulkan 本機 API 支援的所有擴充字串,反之不得報告它們不正確支援的擴充字串。

Device implementations, if not including support for Vulkan 1.0:

  • [C-2-1] MUST NOT declare any of the Vulkan feature flags (eg android.hardware.vulkan.level , android.hardware.vulkan.version ).
  • [C-2-2] MUST NOT enumerate any VkPhysicalDevice for the Vulkan native API vkEnumeratePhysicalDevices() .
7.1.4.3 渲染腳本
7.1.4.4 2D 圖形加速

Android 包含一種機制,供應用程式透過使用清單標記android:hardwareAccelerated或直接 API 呼叫來聲明它們希望在應用程式、活動、視窗或視圖層級啟用 2D 圖形的硬體加速。

設備實現:

  • [C-0-1] 必須預設啟用硬體加速,如果開發者提出請求,則必須透過設定 android:hardwareAccelerated="false" 或直接透過 Android View API 停用硬體加速來停用硬體加速。
  • [C-0-2] 必須表現出與硬體加速的 Android SDK 文件一致的行為。

Android 包含一個 TextureView 對象,可讓開發人員直接將硬體加速的 OpenGL ES 紋理集成為 UI 層次結構中的渲染目標。

  • [C-0-3] 必須支援 TextureView API,並且必須表現出與上游 Android 實作一致的行為。
7.1.4.5 廣色域顯示器

If device implementations claim support for wide-gamut displays through Display.isWideColorGamut() , they:

  • [C-1-1] 必須具有經過顏色校準的顯示器。
  • [C-1-2] 顯示器的色域必須完全覆蓋 CIE 1931 xyY 空間中的 sRGB 色域。
  • [C-1-3] MUST have a display whose gamut has an area of at least 90% of NTSC 1953 in CIE 1931 xyY space.
  • [C-1-4] MUST support OpenGL ES 3.0, 3.1, or 3.2 and report it properly.
  • [C-1-5] MUST advertise support for the EGL_KHR_no_config_context , EGL_EXT_pixel_format_float , EGL_KHR_gl_colorspace , EGL_EXT_colorspace_scrgb_linear , and EGL_GL_colorspace_display_p3 extensions.
  • [SR] Are STRONGLY RECOMMENDED to support GL_EXT_sRGB .

相反,如果設備實作不支援廣色域顯示,則:

  • [C-2-1] 儘管螢幕色域未定義,但應覆蓋 CIE 1931 xyY 空間中 100% 或更多的 sRGB。

7.1.5。舊版應用程式相容模式

Android 指定了一種“相容模式”,在該模式下,框架以“正常”螢幕尺寸等效(320dp 寬度)模式運行,以便為未針對螢幕尺寸獨立之前的舊版Android 開發的遺留應用程式帶來好處。

7.1.6。螢幕技術

Android 平台包含允許應用程式向顯示器呈現豐富圖形的 API。除非本文檔特別允許,否則裝置必須支援 Android SDK 定義的所有這些 API。

設備實現:

  • [C-0-1] MUST support displays capable of rendering 16-bit color graphics.
  • 應支援能夠顯示 24 位元彩色圖形的顯示器。
  • [C-0-2] MUST support displays capable of rendering animations.
  • [C-0-3] MUST use the display technology that have a pixel aspect ratio (PAR) between 0.9 and 1.15.也就是說,像素長寬比必須接近正方形 (1.0),容差為 10 ~ 15%。

7.1.7。輔助顯示器

Android includes support for secondary display to enable media sharing capabilities and developer APIs for accessing external displays.

如果裝置實現透過有線、無線或嵌入式附加顯示器連接支援外部顯示器,則:

  • [C-1-1] MUST implement the DisplayManager system service and API as described in the Android SDK documentation.

7.2.輸入裝置

設備實現:

7.2.1.鍵盤

如果裝置實作包括對第三方輸入法編輯器 (IME) 應用程式的支持,則它們:

Device implementations: [C-0-1] MUST NOT include a hardware keyboard that does not match one of the formats specified in android.content.res.Configuration.keyboard (QWERTY or 12-key). SHOULD include additional soft keyboard implementations. * 可能包括硬體鍵盤。

7.2.2.非觸控式導航

Android 支援方向鍵、軌跡球和滾輪作為非觸控導航機制。

設備實現:

如果設備實現缺乏非觸控導航,它們:

  • [C-1-1] 必須提供合理的替代使用者介面機制來選擇和編輯文本,且與輸入管理引擎相容。上游 Android 開源實作包括適合與缺乏非觸控導航輸入的裝置一起使用的選擇機制。

7.2.3.導航鍵

HomeRecentsBack功能通常透過與專用實體按鈕或觸控螢幕的不同部分進行互動來提供,對於 Android 導航範例至關重要,因此,裝置實現:

  • [C-0-1] MUST provide a user affordance to launch installed applications that have an activity with the <intent-filter> set with ACTION=MAIN and CATEGORY=LAUNCHER or CATEGORY=LEANBACK_LAUNCHER for Television device implementations. The Home function SHOULD be the mechanism for this user affordance.
  • SHOULD provide buttons for the Recents and Back function.

If the Home, Recents, or Back functions are provided, they:

  • [C-1-1] MUST be accessible with a single action (eg tap, double-click or gesture) when any of them are accessible.
  • [C-1-2] MUST provide a clear indication of which single action would trigger each function. Having a visible icon imprinted on the button, showing a software icon on the navigation bar portion of the screen, or walking the user through a guided step-by-step demo flow during the out- thr- through a guided step-by-step demo flow during the out- thr- through a guided step-by-step demo flow during the out-”指示。

設備實現:

  • [SR] are STRONGLY RECOMMENDED to not provide the input mechanism for the Menu function as it is deprecated in favor of action bar since Android 4.0.

如果設備實作提供選單功能,則它們:

  • [C-2-1] MUST display the action overflow button whenever the action overflow menu popup is not empty and the action bar is visible.
  • [C-2-2] MUST NOT modify the position of the action overflow popup displayed by selecting the overflow button in the action bar, but MAY render the action overflow popup at a mod position on the ifiedscreen render the action overflow popup at a mod position on the ifieden playen it playen playupby功能。

If device implementations do not provide the Menu function, for backwards compatibility, they:

  • [C-3-1] MUST make the Menu function available to applications when targetSdkVersion is less than 10, either by a physical button, a software key, or gestures. This Menu function should be accessible unless hidden together with other navigation functions.

If device implementations provide the Assist function , they:

  • [C-4-1] MUST make the Assist function accessible with a single action (eg tap, double-click or gesture) when other navigation keys are accessible.
  • [SR] STRONGLY RECOMMENDED to use long press on HOME function as this designated interaction.

If device implementations use a distinct portion of the screen to display the navigation keys, they:

  • [C-5-1] Navigation keys MUST use a distinct portion of the screen, not available to applications, and MUST NOT obscure or otherwise interfere with the portion of the screen available to applications.
  • [C-5-2] MUST make available a portion of the display to applications that meets the requirements defined in section 7.1.1 .
  • [C-5-3] MUST honor the flags set by the app through the View.setSystemUiVisibility() API method, so that this distinct portion of the screen (aka the navigation bar) is properly hidden away as documented in the SDK.

7.2.4. Touchscreen Input

Android 支援各種指針輸入系統,例如觸控螢幕、觸控板和假觸控輸入裝置。 Touchscreen-based device implementations are associated with a display such that the user has the impression of directly manipulating items on screen.由於使用者直接觸摸螢幕,系統不需要任何額外的功能來指示正在操作的物件。

設備實現:

  • SHOULD have a pointer input system of some kind (either mouse-like or touch).
  • SHOULD support fully independently tracked pointers.

If device implementations include a touchscreen (single-touch or better), they:

  • [C-1-1] MUST report TOUCHSCREEN_FINGER for the Configuration.touchscreen API field.
  • [C-1-2] MUST report the android.hardware.touchscreen and android.hardware.faketouch feature flags

If device implementations include a touchscreen that can track more than a single touch, they:

  • [C-2-1] MUST report the appropriate feature flags android.hardware.touchscreen.multitouch , android.hardware.touchscreen.multitouch.distinct , android.hardware.touchscreen.multitouch.jazzhand corresponding to the type of the specific touchscreen on the裝置.

If device implementations do not include a touchscreen (and rely on a pointer device only) and meet the fake touch requirements in section 7.2.5 , they:

  • [C-3-1] MUST NOT report any feature flag starting with android.hardware.touchscreen and MUST report only android.hardware.faketouch .

7.2.5. Fake Touch Input

Fake touch interface provides a user input system that approximates a subset of touchscreen capabilities.例如,驅動螢幕上遊標的滑鼠或遙控器類似於觸摸,但需要使用者先指向或聚焦,然後按一下。許多輸入裝置(例​​如滑鼠、觸控板、基於陀螺儀的空中滑鼠、陀螺儀指標、操縱桿和多點觸控觸控板)都可以支援假觸控互動。 Android includes the feature constant android.hardware.faketouch, which corresponds to a high-fidelity non-touch (pointer-based) input device such as a mouse or trackpad that can adequately emulate touch-based input (including basic gesture support), and indicates that the device supports an emulated subset of touchscreen functionality.

If device implementations do not include a touchscreen but include another pointer input system which they want to make available, they:

  • SHOULD declare support for the android.hardware.faketouch feature flag.

If device implementations declare support for android.hardware.faketouch , they:

  • [C-1-1] MUST report the absolute X and Y screen positions of the pointer location and display a visual pointer on the screen.
  • [C-1-2] MUST report touch event with the action code that specifies the state change that occurs on the pointer going down or up on the screen .
  • [C-1-3] MUST support pointer down and up on an object on the screen, which allows users to emulate tap on an object on the screen.
  • [C-1-4] MUST support pointer down, pointer up, pointer down then pointer up in the same place on an object on the screen within a time threshold, which allows users to emulate double tap on an object on the screen.
  • [C-1-5] MUST support pointer down on an arbitrary point on the screen, pointer move to any other arbitrary point on the screen, followed by a pointer up, which allows users to emulate a touch drag.
  • [C-1-6] 必須支援指針向下,然後允許使用者快速將物件移動到螢幕上的不同位置,然後在螢幕上向上指針,這樣使用者就可以在螢幕上拋出物件。
  • [C-1-7] MUST report TOUCHSCREEN_NOTOUCH for the Configuration.touchscreen API field.

If device implementations declare support for android.hardware.faketouch.multitouch.distinct , they:

  • [C-2-1] MUST declare support for android.hardware.faketouch .
  • [C-2-2] MUST support distinct tracking of two or more independent pointer inputs.

If device implementations declare support for android.hardware.faketouch.multitouch.jazzhand , they:

  • [C-3-1] MUST declare support for android.hardware.faketouch .
  • [C-3-2] MUST support distinct tracking of 5 (tracking a hand of fingers) or more pointer inputs fully independently.

7.2.6。 Game Controller Support

7.2.6.1. Button Mappings

If device implementations declare the android.hardware.gamepad feature flag, they:

  • [C-1-1] MUST have embed a controller or ship with a separate controller in the box, that would provide means to input all the events listed in the below tables.
  • [C-1-2] MUST be capable to map HID events to it's associated Android view.InputEvent constants as listed in the below tables. The upstream Android implementation includes implementation for game controllers that satisfies this requirement.
按鈕HID 用法2安卓按鈕
1 0x09 0x0001 KEYCODE_BUTTON_A (96)
1 0x09 0x0002 KEYCODE_BUTTON_B (97)
X 1 0x09 0x0004 KEYCODE_BUTTON_X (99)
Y 1 0x09 0x0005 KEYCODE_BUTTON_Y (100)
D-pad up 1
D-pad down 1
0x01 0x0039 3 AXIS_HAT_Y 4
D-pad left 1
D-pad right 1
0x01 0x0039 3 AXIS_HAT_X 4
左肩按鈕1 0x09 0x0007 KEYCODE_BUTTON_L1 (102)
Right shoulder button 1 0x09 0x0008 KEYCODE_BUTTON_R1 (103)
Left stick click 1 0x09 0x000E KEYCODE_BUTTON_THUMBL (106)
右搖桿點選1 0x09 0x000F KEYCODE_BUTTON_THUMBR (107)
首頁1 0x0c 0x0223 KEYCODE_HOME (3)
返回1 0x0c 0x0224 KEYCODE_BACK (4)

1關鍵事件

2 上述 HID 用法必須在遊戲手把 CA (0x01 0x0005) 內聲明。

3 此用法必須具有邏輯最小值 0、邏輯最大值 7、物理最小值 0、物理最大值 315、單位為度和報告大小 4。邏輯值定義為順時針旋轉遠離垂直軸;例如,邏輯值0表示不旋轉且按下向上按鈕,而邏輯值1表示旋轉45度並且按下向上和向左鍵。

4運動事件

模擬控制1 HID 使用安卓按鈕
左扳機0x02 0x00C5 AXIS_LTRIGGER
右邊扳機0x02 0x00C4 AXIS_RTRIGGER
左搖桿0x01 0x0030
0x01 0x0031
軸_X
Y軸
右搖桿0x01 0x0032
0x01 0x0035
軸_Z
軸_RZ

1 個運動事件

7.2.7.遙控

有關設備特定要求,請參閱第 2.3.1 節

7.3.感應器

如果裝置實作包含特定的感測器類型,且該感測器類型具有供第三方開發人員使用的相應 API,則裝置實作必須實作該 API,如 Android SDK 文件和有關感測器的 Android 開源文件中所述。

設備實現:

  • [C-0-1] MUST accurately report the presence or absence of sensors per the android.content.pm.PackageManager class.
  • [C-0-2] MUST return an accurate list of supported sensors via the SensorManager.getSensorList() and similar methods.
  • [C-0-3] MUST behave reasonably for all other sensor APIs (for example, by returning true or false as appropriate when applications attempt to register listeners, not calling sensor listeners when the corresponding sensors are not present; etc.).

如果裝置實作包含特定感測器類型,且該感測器類型具有供第三方開發人員使用的對應 API,則它們:

  • [C-1-1] 必須使用 Android SDK 文件中定義的每種感測器類型的相關國際單位制(公制)值來報告所有感測器測量值
  • [C-1-2] MUST report sensor data with a maximum latency of 100 milliseconds
  • 2 * sample_time for the case of a sensor streamed with a minimum required latency of 5 ms + 2 * sample_time when the application processor is active.此延遲不包括任何過濾延遲。
  • [C-1-3] 必須在啟動感測器的 400 毫秒 + 2 * 樣本時間內報告第一個感測器樣本。此樣本的準確度為 0 是可以接受的。
  • [SR] SHOULD report the event time in nanoseconds as defined in the Android SDK documentation, representing the time the event happened and synchronized with the SystemClock.elapsedRealtimeNano() clock. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to the future platform releases where this might become a REQUIRED component. The synchronization error SHOULD be below 100 milliseconds.

  • [C-1-7] For any API indicated by the Android SDK documentation to be a continuous sensor , device implementations MUST continuously provide periodic data samples that SHOULD have a jitter below 3%, where jitter is defined連續事件之間報告的時間戳記值的數量。

  • [C-1-8] MUST ensure that the sensor event stream MUST NOT prevent the device CPU from entering a suspend state or waking up from a suspend state.

  • 當多個感測器被啟動時,功耗不應超過各個感測器報告的功耗總和。

上面的列表並不全面; Android SDK 和 Android 開源文件在感測器上記錄的行為被視為具有權威性。

某些感測器類型是複合的,這意味著它們可以從一個或多個其他感測器提供的數據中導出。 (例如方向感測器和線性加速度感測器。)

設備實現:

  • 當這些感測器類型包含感測器類型中所述的必備實體感測器時,應實現這些感測器類型。

如果設備實現包括複合感測器,則它們:

  • [C-2-1] 必須按照有關複合感測器的 Android 開源文件中的說明實現感測器。

7.3.1.加速度計

  • 設備實現應包括3軸加速度計。

如果設備實現包括 3 軸加速計,則:

  • [C-1-1] 必須能夠以至少 50 Hz 的頻率報告事件。
  • [C-1-2] MUST implement and report TYPE_ACCELEROMETER sensor.
  • [C-1-3] 必須符合 Android API 中詳述的Android 感測器座標系
  • [C-1-4] 必須能夠在任何軸上從自由落體到四倍重力 (4g) 或以上的情況下進行測量。
  • [C-1-5] 解析度必須至少為 12 位元。
  • [C-1-6] 標準差不得大於 0.05 m/s^,其中標準差應根據在至少 3 秒的時間內以最快採樣率收集的樣本按軸計算。
  • [SR] are STRONGLY RECOMMENDED to implement the TYPE_SIGNIFICANT_MOTION composite sensor.
  • [SR] are STRONGLY RECOMMENDED to implement the TYPE_ACCELEROMETER_UNCALIBRATED sensor if online accelerometer calibration is available.
  • SHOULD implement the TYPE_SIGNIFICANT_MOTION , TYPE_TILT_DETECTOR , TYPE_STEP_DETECTOR , TYPE_STEP_COUNTER composite sensors as described in the Android SDK document.
  • 應報告至少 200 Hz 的事件。
  • 分辨率應至少為 16 位元。
  • 如果特性在生命週期內發生變化,則應在使用時進行校準並進行補償,並在設備重新啟動之間保留補償參數。
  • 應進行溫度補償。
  • SHOULD also implement TYPE_ACCELEROMETER_UNCALIBRATED sensor.

If device implementations include a 3-axis accelerometer and any of the TYPE_SIGNIFICANT_MOTION , TYPE_TILT_DETECTOR , TYPE_STEP_DETECTOR , TYPE_STEP_COUNTER composite sensors are implemented:

  • [C-2-1] The sum of their power consumption MUST always be less than 4 mW.
  • 當設備處於動態或靜態條件時,每個功率應低於 2 mW 和 0.5 mW。

If device implementations include a 3-axis accelerometer and a gyroscope sensor, they:

  • [C-3-1] MUST implement the TYPE_GRAVITY and TYPE_LINEAR_ACCELERATION composite sensors.
  • SHOULD implement the TYPE_GAME_ROTATION_VECTOR composite sensor.
  • [SR] Existing and new Android devices are STRONGLY RECOMMENDED to implement the TYPE_GAME_ROTATION_VECTOR sensor.

If device implementations include a 3-axis accelerometer, a gyroscope sensor and a magnetometer sensor, they:

  • [C-4-1] MUST implement a TYPE_ROTATION_VECTOR composite sensor.

7.3.2.磁力計

  • Device implementations SHOULD include a 3-axis magnetometer (compass).

If device implementations include a 3-axis magnetometer, they:

  • [C-1-1] MUST implement the TYPE_MAGNETIC_FIELD sensor.
  • [C-1-2] MUST be able to report events up to a frequency of at least 10 Hz and SHOULD report events up to at least 50 Hz.
  • [C-1-3] 必須符合 Android API 中詳述的Android 感測器座標系
  • [C-1-4] MUST be capable of measuring between -900 µT and +900 µT on each axis before saturating.
  • [C-1-5] MUST have a hard iron offset value less than 700 µT and SHOULD have a value below 200 µT, by placing the magnetometer far from dynamic (current-induced) and static (magnet-induced) magnetic fields.
  • [C-1-6] MUST have a resolution equal or denser than 0.6 µT.
  • [C-1-7] MUST support online calibration and compensation of the hard iron bias, and preserve the compensation parameters between device reboots.
  • [C-1-8] MUST have the soft iron compensation applied—the calibration can be done either while in use or during the production of the device.
  • [C-1-9] MUST have a standard deviation, calculated on a per axis basis on samples collected over a period of at least 3 seconds at the fastest sampling rate, no greater than 1.5 µT; SHOULD have a standard deviation no greater than 0.5 µT.
  • SHOULD implement TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.
  • [SR] Existing and new Android devices are STRONGLY RECOMMENDED to implement the TYPE_MAGNETIC_FIELD_UNCALIBRATED sensor.

If device implementations include a 3-axis magnetometer, an accelerometer sensor and a gyroscope sensor, they:

  • [C-2-1] MUST implement a TYPE_ROTATION_VECTOR composite sensor.

If device implementations include a 3-axis magnetometer, an accelerometer, they:

  • MAY implement the TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor.

If device implementations include a 3-axis magnetometer, an accelerometer and TYPE_GEOMAGNETIC_ROTATION_VECTOR sensor, they:

  • [C-3-1] MUST consume less than 10 mW.
  • SHOULD consume less than 3 mW when the sensor is registered for batch mode at 10 Hz.

7.3.3.全球定位系統

設備實現:

  • SHOULD include a GPS/GNSS receiver.

If device implementations include a GPS/GNSS receiver and report the capability to applications through the android.hardware.location.gps feature flag, they:

  • [C-1-1] MUST support location outputs at a rate of at least 1 Hz when requested via LocationManager#requestLocationUpdate .
  • [C-1-2] MUST be able to determine the location in open-sky conditions (strong signals, negligible multipath, HDOP < 2) within 10 seconds (fast time to first fix), when connected to a 0.5 Mbps or faster data speed internet connection. This requirement is typically met by the use of some form of Assisted or Predicted GPS/GNSS technique to minimize GPS/GNSS lock-on time (Assistance data includes Reference Time, Reference Location and Satellite Ephemeris/Clock).
    • [SR] After making such a location calculation, it is STRONGLY RECOMMENDED for the device to be able to determine its location, in open sky, within 10 seconds, when location requests are restarted, up to an hour after the initial location calculation, even when the subsequent request is made without a data connection, and/or after a power cycle.
  • In open sky conditions after determining the location, while stationary or moving with less than 1 meter per second squared of acceleration:

    • [C-1-3] MUST be able to determine location within 20 meters, and speed within 0.5 meters per second, at least 95% of the time.
    • [C-1-4] MUST simultaneously track and report via GnssStatus.Callback at least 8 satellites from one constellation.
    • SHOULD be able to simultaneously track at least 24 satellites, from multiple constellations (eg GPS + at least one of Glonass, Beidou, Galileo).
    • [C-1-5] MUST report the GNSS technology generation through the test API 'getGnssYearOfHardware'.
    • [SR] Continue to deliver normal GPS/GNSS location outputs during an emergency phone call.
    • [SR] Report GNSS measurements from all constellations tracked (as reported in GnssStatus messages), with the exception of SBAS.
    • [SR] Report AGC, and Frequency of GNSS measurement.
    • [SR] Report all accuracy estimates (including Bearing, Speed, and Vertical) as part of each GPS Location.
    • [SR] are STRONGLY RECOMMENDED to meet as many as possible from the additional mandatory requirements for devices reporting the year "2016" or "2017" through the Test API LocationManager.getGnssYearOfHardware() .

If device implementations include a GPS/GNSS receiver and report the capability to applications through the android.hardware.location.gps feature flag and the LocationManager.getGnssYearOfHardware() Test API reports the year "2016" or newer, they:

  • [C-2-1] MUST report GPS measurements, as soon as they are found, even if a location calculated from GPS/GNSS is not yet reported.
  • [C-2-2] MUST report GPS pseudoranges and pseudorange rates, that, in open-sky conditions after determining the location, while stationary or moving with less than 0.2 meter per second squared of acceleration, are sufficient to calculate position within 20 meters, and speed within 0.2 meters per second, at least 95% of the time.

If device implementations include a GPS/GNSS receiver and report the capability to applications through the android.hardware.location.gps feature flag and the LocationManager.getGnssYearOfHardware() Test API reports the year "2017" or newer, they:

  • [C-3-1] MUST continue to deliver normal GPS/GNSS location outputs during an emergency phone call.
  • [C-3-2] MUST report GNSS measurements from all constellations tracked (as reported in GnssStatus messages), with the exception of SBAS.
  • [C-3-3] MUST report AGC, and Frequency of GNSS measurement.
  • [C-3-4] MUST report all accuracy estimates (including Bearing, Speed, and Vertical) as part of each GPS Location.

7.3.4.陀螺儀

設備實現:

  • SHOULD include a gyroscope (angular change sensor).
  • SHOULD NOT include a gyroscope sensor unless a 3-axis accelerometer is also included.

If device implementations include a gyroscope, they:

  • [C-1-1] 必須能夠以至少 50 Hz 的頻率報告事件。
  • [C-1-2] MUST implement the TYPE_GYROSCOPE sensor and SHOULD also implement TYPE_GYROSCOPE_UNCALIBRATED sensor.
  • [C-1-3] MUST be capable of measuring orientation changes up to 1,000 degrees per second.
  • [C-1-4] MUST have a resolution of 12-bits or more and SHOULD have a resolution of 16-bits or more.
  • [C-1-5] MUST be temperature compensated.
  • [C-1-6] MUST be calibrated and compensated while in use, and preserve the compensation parameters between device reboots.
  • [C-1-7] MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz, or rad^2 / s). The variance is allowed to vary with the sampling rate, but MUST be constrained by this value. In other words, if you measure the variance of the gyro at 1 Hz sampling rate it SHOULD be no greater than 1e-7 rad^2/s^2.
  • [SR] Existing and new Android devices are STRONGLY RECOMMENDED to implement the SENSOR_TYPE_GYROSCOPE_UNCALIBRATED sensor.
  • [SR] Calibration error is STRONGLY RECOMMENDED to be less than 0.01 rad/s when device is stationary at room temperature.
  • 應報告至少 200 Hz 的事件。

If device implementations include a gyroscope, an accelerometer sensor and a magnetometer sensor, they:

  • [C-2-1] MUST implement a TYPE_ROTATION_VECTOR composite sensor.

If device implementations include a gyroscope and a accelerometer sensor, they:

  • [C-3-1] MUST implement the TYPE_GRAVITY and TYPE_LINEAR_ACCELERATION composite sensors.
  • [SR] Existing and new Android devices are STRONGLY RECOMMENDED to implement the TYPE_GAME_ROTATION_VECTOR sensor.
  • SHOULD implement the TYPE_GAME_ROTATION_VECTOR composite sensor.

7.3.5。晴雨表

  • Device implementations SHOULD include a barometer (ambient air pressure sensor).

If device implementations include a barometer, they:

  • [C-1-1] MUST implement and report TYPE_PRESSURE sensor.
  • [C-1-2] MUST be able to deliver events at 5 Hz or greater.
  • [C-1-3] MUST be temperature compensated.
  • [SR] STRONGLY RECOMMENDED to be able to report pressure measurements in the range 300hPa to 1100hPa.
  • SHOULD have an absolute accuracy of 1hPa.
  • SHOULD have a relative accuracy of 0.12hPa over 20hPa range (equivalent to ~1m accuracy over ~200m change at sea level).

7.3.6。溫度計

Device implementations: MAY include an ambient thermometer (temperature sensor). MAY but SHOULD NOT include a CPU temperature sensor.

If device implementations include an ambient thermometer (temperature sensor), they:

  • [C-1-1] MUST be defined as SENSOR_TYPE_AMBIENT_TEMPERATURE and MUST measure the ambient (room/vehicle cabin) temperature from where the user is interacting with the device in degrees Celsius.
  • [C-1-2] MUST be defined as SENSOR_TYPE_TEMPERATURE .
  • [C-1-3] MUST measure the temperature of the device CPU.
  • [C-1-4] MUST NOT measure any other temperature.

Note the SENSOR_TYPE_TEMPERATURE sensor type was deprecated in Android 4.0.

7.3.7.光度計

  • Device implementations MAY include a photometer (ambient light sensor).

7.3.8.接近感測器

  • 設備實現可能包括接近感測器。

If device implementations include a proximity sensor, they:

  • [C-1-1] MUST measure the proximity of an object in the same direction as the screen.也就是說,必須將接近感測器定向以檢測靠近螢幕的對象,因為該感測器類型的主要目的是檢測使用者使用的手機。 If device implementations include a proximity sensor with any other orientation, it MUST NOT be accessible through this API.
  • [C-1-2] MUST have 1-bit of accuracy or more.

7.3.9. High Fidelity Sensors

If device implementations include a set of higher quality sensors as defined in this section, and make available them to third-party apps, they:

  • [C-1-1] MUST identify the capability through the android.hardware.sensor.hifi_sensors feature flag.

If device implementations declare android.hardware.sensor.hifi_sensors , they:

  • [C-2-1] MUST have a TYPE_ACCELEROMETER sensor which:

    • MUST have a measurement range between at least -8g and +8g.
    • MUST have a measurement resolution of at least 1024 LSB/G.
    • MUST have a minimum measurement frequency of 12.5 Hz or lower.
    • MUST have a maximum measurement frequency of 400 Hz or higher.
    • MUST have a measurement noise not above 400 uG/√Hz.
    • MUST implement a non-wake-up form of this sensor with a buffering capability of at least 3000 sensor events.
    • MUST have a batching power consumption not worse than 3 mW.
    • SHOULD have a stationary noise bias stability of \<15 μg √Hz from 24hr static dataset.
    • SHOULD have a bias change vs. temperature of ≤ +/- 1mg / °C.
    • SHOULD have a best-fit line non-linearity of ≤ 0.5%, and sensitivity change vs. temperature of ≤ 0.03%/C°.
    • SHOULD have white noise spectrum to ensure adequate qualification of sensor's noise integrity.
  • [C-2-2] MUST have a TYPE_ACCELEROMETER_UNCALIBRATED with the same quality requirements as TYPE_ACCELEROMETER .

  • [C-2-3] MUST have a TYPE_GYROSCOPE sensor which:

    • MUST have a measurement range between at least -1000 and +1000 dps.
    • MUST have a measurement resolution of at least 16 LSB/dps.
    • MUST have a minimum measurement frequency of 12.5 Hz or lower.
    • MUST have a maximum measurement frequency of 400 Hz or higher.
    • MUST have a measurement noise not above 0.014°/s/√Hz.
    • SHOULD have a stationary bias stability of < 0.0002 °/s √Hz from 24-hour static dataset.
    • SHOULD have a bias change vs. temperature of ≤ +/- 0.05 °/ s / °C.
    • SHOULD have a sensitivity change vs. temperature of ≤ 0.02% / °C.
    • SHOULD have a best-fit line non-linearity of ≤ 0.2%.
    • SHOULD have a noise density of ≤ 0.007 °/s/√Hz.
    • SHOULD have white noise spectrum to ensure adequate qualification of sensor's noise integrity.
    • SHOULD have calibration error less than 0.002 rad/s in temperature range 10 ~ 40 ℃ when device is stationary.
  • [C-2-4] MUST have a TYPE_GYROSCOPE_UNCALIBRATED with the same quality requirements as TYPE_GYROSCOPE .

  • [C-2-5] MUST have a TYPE_GEOMAGNETIC_FIELD sensor which:
    • MUST have a measurement range between at least -900 and +900 uT.
    • MUST have a measurement resolution of at least 5 LSB/uT.
    • MUST have a minimum measurement frequency of 5 Hz or lower.
    • MUST have a maximum measurement frequency of 50 Hz or higher.
    • 測量噪音必須不高於 0.5 uT。
  • [C-2-6] MUST have a TYPE_MAGNETIC_FIELD_UNCALIBRATED with the same quality requirements as TYPE_GEOMAGNETIC_FIELD and in addition:
    • 必須實現該感測器的非喚醒形式,並具有至少 600 個感測器事件的緩衝能力。
    • SHOULD have white noise spectrum to ensure adequate qualification of sensor's noise integrity.
  • [C-2-7] MUST have a TYPE_PRESSURE sensor which:
    • 測量範圍必須至少在 300 至 1100 hPa 之間。
    • 測量分辨率必須至少為 80 LSB/hPa。
    • 最小測量頻率必須為 1 Hz 或更低。
    • 最大測量頻率必須為 10 Hz 或更高。
    • 量測雜訊必須不高於 2 Pa/√Hz。
    • 必須實現該感測器的非喚醒形式,並具有至少 300 個感測器事件的緩衝能力。
    • 批次功耗必須不低於 2 mW。
  • [C-2-8] MUST have a TYPE_GAME_ROTATION_VECTOR sensor which:
    • 必須實現該感測器的非喚醒形式,並具有至少 300 個感測器事件的緩衝能力。
    • 批次功耗必須不低於 4 mW。
  • [C-2-9] MUST have a TYPE_SIGNIFICANT_MOTION sensor which:
    • 設備靜態時功耗不得低於 0.5 mW,設備移動時功耗不得低於 1.5 mW。
  • [C-2-10] MUST have a TYPE_STEP_DETECTOR sensor which:
    • 必須實現該感測器的非喚醒形式,並具有至少 100 個感測器事件的緩衝能力。
    • 設備靜態時功耗不得低於 0.5 mW,設備移動時功耗不得低於 1.5 mW。
    • 批次功耗必須不低於 4 mW。
  • [C-2-11] MUST have a TYPE_STEP_COUNTER sensor which:
    • 設備靜態時功耗不得低於 0.5 mW,設備移動時功耗不得低於 1.5 mW。
  • [C-2-12] MUST have a TILT_DETECTOR sensor which:
    • 設備靜態時功耗不得低於 0.5 mW,設備移動時功耗不得低於 1.5 mW。
  • [C-2-13] The event timestamp of the same physical event reported by the Accelerometer, Gyroscope sensor and Magnetometer MUST be within 2.5 milliseconds of each other.
  • [C-2-14] 陀螺儀感測器事件時間戳記必須與相機子系統處於同一時基,且誤差在 1 毫秒以內。
  • [C-2-15] 當上述任何實體感測器上的資料可用於應用程式時,必須在 5 毫秒內將樣本傳送到應用程式。
  • [C-2-16] MUST not have a power consumption higher than 0.5 mW when device is static and 2.0 mW when device is moving when any combination of the following sensors are enabled:
    • SENSOR_TYPE_SIGNIFICANT_MOTION
    • SENSOR_TYPE_STEP_DETECTOR
    • SENSOR_TYPE_STEP_COUNTER
    • SENSOR_TILT_DETECTORS
  • [C-2-17] MAY have a TYPE_PROXIMITY sensor, but if present MUST have a minimum buffer capability of 100 sensor events.

請注意,本節中的所有功耗要求不包括應用處理器的功耗。它包括整個感測器鏈(感測器、任何支援電路、任何專用感測器處理系統等)消耗的功率。

如果設備實現包括直接感測器支持,則它們:

  • [C-3-1] MUST correctly declare support of direct channel types and direct report rates level through the isDirectChannelTypeSupported and getHighestDirectReportRateLevel API.
  • [C-3-2] MUST support at least one of the two sensor direct channel types for all sensors that declare support for sensor direct channel
  • TYPE_HARDWARE_BUFFER
  • TYPE_MEMORY_FILE
  • 應支援透過感測器直接通道對以下類型的主感測器(非喚醒變體)進行事件報告:
  • TYPE_ACCELEROMETER
  • TYPE_ACCELEROMETER_UNCALIBRATED
  • TYPE_GYROSCOPE
  • TYPE_GYROSCOPE_UNCALIBRATED
  • TYPE_MAGNETIC_FIELD
  • TYPE_MAGNETIC_FIELD_UNCALIBRATED

7.3.10.指紋感應器

如果裝置實作包括安全鎖定螢幕,則:

  • SHOULD include a fingerprint sensor.

If device implementations include a fingerprint sensor and make the sensor available to third-party apps, they:

  • [C-1-1] MUST declare support for the android.hardware.fingerprint feature.
  • [C-1-2] MUST fully implement the corresponding API as described in the Android SDK documentation.
  • [C-1-3] MUST have a false acceptance rate not higher than 0.002%.
  • [SR] Are STRONGLY RECOMMENDED to have a spoof and imposter acceptance rate not higher than 7%.
  • [C-1-4] MUST disclose that this mode may be less secure than a strong PIN, pattern, or password and clearly enumerate the risks of enabling it, if the spoof and imposter acceptance rates are higher than 7%.
  • [C-1-5] MUST rate limit attempts for at least 30 seconds after five false trials for fingerprint verification.
  • [C-1-6] MUST have a hardware-backed keystore implementation, and perform the fingerprint matching in a Trusted Execution Environment (TEE) or on a chip with a secure channel to the TEE.
  • [C-1-7] MUST have all identifiable fingerprint data encrypted and cryptographically authenticated such that they cannot be acquired, read or altered outside of the Trusted Execution Environment (TEE) as documented in the implementation guidelines on the Android Open Source Project site.
  • [C-1-8] MUST prevent adding a fingerprint without first establishing a chain of trust by having the user confirm existing or add a new device credential (PIN/pattern/password) that's secured by TEE; the Android Open Source Project implementation provides the mechanism in the framework to do so.
  • [C-1-9] MUST NOT enable 3rd-party applications to distinguish between individual fingerprints.
  • [C-1-10] MUST honor the DevicePolicyManager.KEYGUARD_DISABLE_FINGERPRINT flag.
  • [C-1-11] MUST, when upgraded from a version earlier than Android 6.0, have the fingerprint data securely migrated to meet the above requirements or removed.
  • [SR] Are STRONGLY RECOMMENDED to have a false rejection rate of less than 10%, as measured on the device.
  • [SR] Are STRONGLY RECOMMENDED to have a latency below 1 second, measured from when the fingerprint sensor is touched until the screen is unlocked, for one enrolled finger.
  • SHOULD use the Android Fingerprint icon provided in the Android Open Source Project.

7.3.11. Android Automotive-only sensors

Automotive-specific sensors are defined in the android.car.CarSensorManager API .

7.3.11.1.目前檔位

See Section 2.5.1 for device-specific requirements.

7.3.11.2.日夜模式

See Section 2.5.1 for device-specific requirements.

7.3.11.3.駕駛狀態

See Section 2.5.1 for device-specific requirements.

7.3.11.4.輪速

See Section 2.5.1 for device-specific requirements.

7.3.12.姿勢感測器

設備實現:

  • 可支援 6 個自由度的姿態感測器。

如果設備實現支援具有 6 個自由度的姿態感測器,則它們:

  • [C-1-1] MUST implement and report TYPE_POSE_6DOF sensor.
  • [C-1-2] 必須比單獨的旋轉向量更準確。

7.4.數據連接

7.4.1.電話

“Telephony” as used by the Android APIs and this document refers specifically to hardware related to placing voice calls and sending SMS messages via a GSM or CDMA network. While these voice calls may or may not be packet-switched, they are for the purposes of Android considered independent of any data connectivity that may be implemented using the same network. In other words, the Android “telephony” functionality and APIs refer specifically to voice calls and SMS.例如,無法撥打電話或發送/接收 SMS 訊息的設備實作不被視為電話設備,無論它們是否使用蜂窩網路進行數據連接。

  • Android 可以在不包含電話硬體的裝置上使用。也就是說,Android 相容於手機以外的裝置。

如果設備實作包括 GSM 或 CDMA 電話,則:

  • [C-1-1] MUST declare the android.hardware.telephony feature flag and other sub-feature flags according to the technology.
  • [C-1-2] 必須為該技術的 API 提供全面支援。

如果設備實作不包括電話硬件,則:

  • [C-2-1] 必須將完整 API 實作為無操作。
7.4.1.1. Number Blocking Compatibility

If device implementations report the android.hardware.telephony feature , they:

  • [C-1-1] MUST include number blocking support
  • [C-1-2] MUST fully implement BlockedNumberContract and the corresponding API as described in the SDK documentation.
  • [C-1-3] MUST block all calls and messages from a phone number in 'BlockedNumberProvider' without any interaction with apps. The only exception is when number blocking is temporarily lifted as described in the SDK documentation.
  • [C-1-4] MUST NOT write to the platform call log provider for a blocked call.
  • [C-1-5] MUST NOT write to the Telephony provider for a blocked message.
  • [C-1-6] MUST implement a blocked numbers management UI, which is opened with the intent returned by TelecomManager.createManageBlockedNumbersIntent() method.
  • [C-1-7] MUST NOT allow secondary users to view or edit the blocked numbers on the device as the Android platform assumes the primary user to have full control of the telephony services, a single instance, on the device. All blocking related UI MUST be hidden for secondary users and the blocked list MUST still be respected.
  • SHOULD migrate the blocked numbers into the provider when a device updates to Android 7.0.
7.4.1.2。 Telecom API

If device implementations report android.hardware.telephony , they:

  • [C-SR] Are STRONGLY RECOMMENDED to handle the the audio headset's KEYCODE_MEDIA_PLAY_PAUSE and KEYCODE_HEADSETHOOK events for the android.telecom APIs as below:

7.4.2. IEEE 802.11(無線網路)

設備實現:

  • SHOULD include support for one or more forms of 802.11.

If device implementations include support for 802.11 and expose the functionality to a third-party application, they

  • [C-1-1] MUST implement the corresponding Android API.
  • [C-1-2] MUST report the hardware feature flag android.hardware.wifi .
  • [C-1-3] MUST implement the multicast API as described in the SDK documentation.
  • [C-1-4] MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets (224.0.0.251) at any time of operation including:
    • Even when the screen is not in an active state.
    • For Android Television device implementations, even when in standby power states.
  • SHOULD randomize the source MAC address and sequence number of probe request frames, once at the beginning of each scan, while STA is disconnected.
    • Each group of probe request frames comprising one scan should use one consistent MAC address (SHOULD NOT randomize MAC address halfway through a scan).
    • Probe request sequence number should iterate as normal (sequentially) between the probe requests in a scan
    • Probe request sequence number should randomize between the last probe request of a scan and the first probe request of the next scan
  • SHOULD only allow the following information elements in probe request frames, while STA is disconnected:
    • SSID Parameter Set (0)
    • DS Parameter Set (3)
7.4.2.1.無線直連

設備實現:

  • SHOULD include support for Wi-Fi Direct (Wi-Fi peer-to-peer).

If device implementations include support for Wi-Fi Direct, they:

  • [C-1-1] MUST implement the corresponding Android API as described in the SDK documentation.
  • [C-1-2] MUST report the hardware feature android.hardware.wifi.direct .
  • [C-1-3] MUST support regular Wi-Fi operation.
  • SHOULD support Wi-Fi and Wi-Fi Direct operations concurrently.

設備實現:

If device implementations include support for TDLS and TDLS is enabled by the WiFiManager API, they:

  • [C-1-1] MUST declare support for TDLS through WifiManager.isTdlsSupported .
  • SHOULD use TDLS only when it is possible AND beneficial.
  • SHOULD have some heuristic and NOT use TDLS when its performance might be worse than going through the Wi-Fi access point.
7.4.2.3。無線網路感知

設備實現:

If device implementations include support for Wi-Fi Aware and expose the functionality to third-party apps, then they:

  • [C-1-1] MUST implement the WifiAwareManager APIs as described in the SDK documentation .
  • [C-1-2] MUST declare the android.hardware.wifi.aware feature flag.
  • [C-1-3] MUST support Wi-Fi and Wi-Fi Aware operations concurrently.
  • [C-1-4] MUST randomize the Wi-Fi Aware management interface address at intervals no longer then 30 minutes and whenever Wi-Fi Aware is enabled.
7.4.2.4. Wi-Fi Passpoint

設備實現:

If device implementations include support for Wi-Fi Passpoint, they:

  • [C-1-1] MUST implement the Passpoint related WifiManager APIs as described in the SDK documentation .
  • [C-1-2] MUST support IEEE 802.11u standard, specifically related to Network Discovery and Selection, such as Generic Advertisement Service (GAS) and Access Network Query Protocol (ANQP).

Conversely if device implementations do not include support for Wi-Fi Passpoint:

  • [C-2-1] The implementation of the Passpoint related WifiManager APIs MUST throw an UnsupportedOperationException .

7.4.3.藍牙

If device implementations support Bluetooth Audio profile, they:

  • SHOULD support Advanced Audio Codecs and Bluetooth Audio Codecs (eg LDAC).

If device implementations declare android.hardware.vr.high_performance feature, they:

  • [C-1-1] MUST support Bluetooth 4.2 and Bluetooth LE Data Length Extension.

Android includes support for Bluetooth and Bluetooth Low Energy .

If device implementations include support for Bluetooth and Bluetooth Low Energy, they:

  • [C-2-1] MUST declare the relevant platform features ( android.hardware.bluetooth and android.hardware.bluetooth_le respectively) and implement the platform APIs.
  • SHOULD implement relevant Bluetooth profiles such as A2DP, AVCP, OBEX, etc. as appropriate for the device.

If device implementations include support for Bluetooth Low Energy, they:

  • [C-3-1] MUST declare the hardware feature android.hardware.bluetooth_le .
  • [C-3-2] MUST enable the GATT (generic attribute profile) based Bluetooth APIs as described in the SDK documentation and android.bluetooth .
  • [C-3-3] MUST report the correct value for BluetoothAdapter.isOffloadedFilteringSupported() to indicate whether the filtering logic for the ScanFilter API classes is implemented.
  • [C-3-4] MUST report the correct value for BluetoothAdapter.isMultipleAdvertisementSupported() to indicate whether Low Energy Advertising is supported.
  • SHOULD support offloading of the filtering logic to the bluetooth chipset when implementing the ScanFilter API .
  • SHOULD support offloading of the batched scanning to the bluetooth chipset.
  • SHOULD support multi advertisement with at least 4 slots.

  • [SR] STRONGLY RECOMMENDED to implement a Resolvable Private Address (RPA) timeout no longer than 15 minutes and rotate the address at timeout to protect user privacy.

7.4.4.近場通訊

設備實現:

  • SHOULD include a transceiver and related hardware for Near-Field Communications (NFC).
  • [C-0-1] MUST implement android.nfc.NdefMessage and android.nfc.NdefRecord APIs even if they do not include support for NFC or declare the android.hardware.nfc feature as the classes represent a declare the android.hardware.nfc feature as the classes represent a protocol-presmatent as the classs represent a protocol. 。

If device implementations include NFC hardware and plan to make it available to third-party apps, they:

  • [C-1-1] MUST report the android.hardware.nfc feature from the android.content.pm.PackageManager.hasSystemFeature() method .
  • MUST be capable of reading and writing NDEF messages via the following NFC standards as below:
  • [C-1-2] MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the following NFC standards:
  • NFCA(ISO14443-3A)
  • NFCB(ISO14443-3B)
  • NfcF (JIS X 6319-4)
  • ISODEP(ISO 14443-4)
  • NFC Forum Tag Types 1, 2, 3, 4, 5 (defined by the NFC Forum)
  • [SR] STRONGLY RECOMMENDED to be capable of reading and writing NDEF messages as well as raw data via the following NFC standards. Note that while the NFC standards are stated as STRONGLY RECOMMENDED, the Compatibility Definition for a future version is planned to change these to MUST. These standards are optional in this version but will be required in future versions. Existing and new devices that run this version of Android are very strongly encouraged to meet these requirements now so they will be able to upgrade to the future platform releases.

  • [C-1-3] MUST be capable of transmitting and receiving data via the following peer-to-peer standards and protocols:

  • ISO 18092
  • LLCP 1.2 (defined by the NFC Forum)
  • SDP 1.0(由NFC論壇定義)
  • NDEF Push Protocol
  • SNEP 1.0(由NFC論壇定義)
  • [C-1-4] MUST include support for Android Beam and SHOULD enable Android Beam by default.
  • [C-1-5] MUST be able to send and receive using Android Beam, when Android Beam is enabled or another proprietary NFC P2p mode is turned on.
  • [C-1-6] MUST implement the SNEP default server.預設SNEP伺服器接收到的有效NDEF訊息必須使用android.nfc.ACTION_NDEF_DISCOVERED意圖將其派往應用程式。在設定中停用Android Beam不得停用傳入的NDEF訊息。
  • [C-1-7] MUST honor the android.settings.NFCSHARING_SETTINGS intent to show NFC sharing settings .
  • [C-1-8] MUST implement the NPP server. NPP伺服器接收的訊息必須與SNEP預設伺服器相同。
  • [C-1-9] MUST implement a SNEP client and attempt to send outbound P2P NDEF to the default SNEP server when Android Beam is enabled.如果找不到預設的SNEP伺服器,則客戶端必須嘗試傳送到NPP伺服器。
  • [C-1-10] MUST allow foreground activities to set the outbound P2P NDEF message using android.nfc.NfcAdapter.setNdefPushMessage , and android.nfc.NfcAdapter.setNdefPushMessageCallback , and android.nfc.NfcAdapter.enableForegroundNdefPush .
  • 在發送出站P2P NDEF訊息之前,應使用手勢或螢幕上的確認,例如「觸控梁」。
  • [C-1-11] MUST support NFC Connection handover to Bluetooth when the device supports Bluetooth Object Push Profile.
  • [C-1-12] MUST support connection handover to Bluetooth when using android.nfc.NfcAdapter.setBeamPushUris , by implementing the “ Connection Handover version 1.2 ” and “ Bluetooth Secure Simple Pairing Using NFC version 1.0 ” specs from the NFC Forum. Such an implementation MUST implement the handover LLCP service with service name “urn:nfc:sn:handover” for exchanging the handover request/select records over NFC, and it MUST use the Bluetooth Object Push Profile for the actual Bluetooth data transfer. For legacy reasons (to remain compatible with Android 4.1 devices), the implementation SHOULD still accept SNEP GET requests for exchanging the handover request/select records over NFC. However an implementation itself SHOULD NOT send SNEP GET requests for performing connection handover.
  • [C-1-13] MUST poll for all supported technologies while in NFC discovery mode.
  • 當裝置醒著時,螢幕處於活動狀態並解鎖鎖定螢幕時,應處於NFC發現模式。
  • SHOULD be capable of reading the barcode and URL (if encoded) of Thinfilm NFC Barcode products.

(請注意,上述引用的JIS,ISO和NFC論壇規格不可公開可用的連結。)

Android includes support for NFC Host Card Emulation (HCE) mode.

If device implementations include an NFC controller chipset capable of HCE (for NfcA and/or NfcB) and support Application ID (AID) routing, they:

  • [C-2-1] MUST report the android.hardware.nfc.hce feature constant.
  • [C-2-2] MUST support NFC HCE APIs as defined in the Android SDK.

If device implementations include an NFC controller chipset capable of HCE for NfcF, and implement the feature for third-party applications, they:

  • [C-3-1] MUST report the android.hardware.nfc.hcef feature constant.
  • [C-3-2] MUST implement the NfcF Card Emulation APIs as defined in the Android SDK.

If device implementations include general NFC support as described in this section and support MIFARE technologies (MIFARE Classic, MIFARE Ultralight, NDEF on MIFARE Classic) in the reader/writer role, they:

  • [C-4-1] MUST implement the corresponding Android APIs as documented by the Android SDK.
  • [C-4-2] MUST report the feature com.nxp.mifare from the android.content.pm.PackageManager.hasSystemFeature () method. Note that this is not a standard Android feature and as such does not appear as a constant in the android.content.pm.PackageManager class.

7.4.5。最低網路能力

設備實現:

  • [C-0-1] MUST include support for one or more forms of data networking.具體而言,設備實作必須包括至少一個能夠為200kbit/sec或更高的資料標準的支援。 Examples of technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g, Ethernet, Bluetooth PAN, etc.
  • [C-0-2] MUST include an IPv6 networking stack and support IPv6 communication using the managed APIs, such as java.net.Socket and java.net.URLConnection , as well as the native APIs, such as AF_INET6 sockets.
  • [C-0-3] MUST enable IPv6 by default.
  • MUST ensure that IPv6 communication is as reliable as IPv4, for example.
  • [C-0-4] MUST maintain IPv6 connectivity in doze mode.
  • [C-0-5] Rate-limiting MUST NOT cause the device to lose IPv6 connectivity on any IPv6-compliant network that uses RA lifetimes of at least 180 seconds.
  • SHOULD also include support for at least one common wireless data standard, such as 802.11 (Wi-Fi) when a physical networking standard (such as Ethernet) is the primary data connection
  • MAY implement more than one form of data connectivity.

The required level of IPv6 support depends on the network type, as follows:

If devices implementations support Wi-Fi networks, they:

  • [C-1-1] MUST support dual-stack and IPv6-only operation on Wi-Fi.

If device implementations support Ethernet networks, they:

  • [C-2-1] MUST support dual-stack operation on Ethernet.

If device implementations support cellular data, they:

  • [C-3-1] MUST simultaneously meet these requirements on each network to which it is connected when a device is simultaneously connected to more than one network (eg, Wi-Fi and cellular data), .
  • SHOULD support IPv6 operation (IPv6-only and possibly dual-stack) on cellular data.

7.4.6。同步設定

設備實現:

7.4.7。資料保護程式

If device implementations include a metered connection, they are:

  • [SR] STRONGLY RECOMMENDED to provide the data saver mode.

If device implementations provide the data saver mode, they:

如果設備實作不提供資料保護模式,它們:

  • [C-2-1] MUST return the value RESTRICT_BACKGROUND_STATUS_DISABLED for ConnectivityManager.getRestrictBackgroundStatus()
  • [C-2-2] MUST NOT broadcast ConnectivityManager.ACTION_RESTRICT_BACKGROUND_CHANGED .
  • [C-2-3] MUST have an activity that handles the Settings.ACTION_IGNORE_BACKGROUND_DATA_RESTRICTIONS_SETTINGS intent but MAY implement it as a no-op.

7.5。相機

If device implementations include at least one camera, they:

  • [C-1-1] MUST declare the android.hardware.camera.any feature flag.
  • [C-1-2] MUST be possible for an application 到 simultaneously allocate 3 RGBA_8888 bitmaps equal to the size of the images produced by the largest-resolution捕獲。

7.5.1.後置攝像頭

後置相機是位於顯示器對面裝置側面的相機。也就是說,它像傳統的相機一樣在設備的另一側拍攝場景。

設備實現:

  • SHOULD include a rear-facing camera.

If device implementations include at least one rear-facing camera, they:

  • [C-1-1] MUST report the feature flag android.hardware.camera and android.hardware.camera.any .
  • [C-1-2] MUST have a resolution of at least 2 megapixels.
  • SHOULD have either hardware auto-focus or software auto-focus implemented in the camera driver (transparent to application software).
  • MAY have fixed-focus or EDOF (extended depth of field) hardware.
  • 可能包括閃光燈。

If the Camera includes a flash:

  • [C-2-1] the flash lamp MUST FLASH_MODE_AUTO be lit while an android.hardware.Camera.PreviewCallback instance has been registered on a Camera preview surface, unless the application has explicitly enabled the flash FLASH_MODE_ON on the Camera.Parameters物件。請注意,此約束不適用於裝置的內建系統攝影機應用程序,而僅適用於使用Camera.PreviewCallback的第三方應用程式。

7.5.2.前置鏡頭

前置鏡頭是與顯示器相同的相機。也就是說,通常用於對使用者進行映像的相機,例如視訊會議和類似的應用程式。

設備實現:

  • MAY include a front-facing camera

If device implementations include at least one front-facing camera, they:

  • [C-1-1] MUST report the feature flag android.hardware.camera.any and android.hardware.camera.front .
  • [C-1-2] MUST have a resolution of at least VGA (640x480 pixels).
  • [C-1-3] MUST NOT use a front-facing camera as the default for the Camera API and MUST NOT configure the API to treat a front-facing camera as the default rear-facing camera, even if it is the only camera在設備上。
  • [C-1-5] The camera preview MUST be mirrored horizo​​ntally relative to the orientation specified by the application when the current application has explicitly requested that the Camera display be rotated via a call to the android.hardware.Camera.setDisplayOrientation() 。 Conversely, the preview MUST be mirrored along the device's default horizontal axis when the the current application does not explicitly request that the Camera display be rotated via a call to the android.hardware.Camera.setDisplayOrientation() method.
  • [C-1-6] MUST NOT mirror the final captured still image or video streams returned to application callbacks or committed to media storage.
  • [C-1-7] MUST mirror the image displayed by the postview in the same manner as the camera preview image stream.
  • MAY include features (such as auto-focus, flash, etc.) available to rear-facing cameras as described in section 7.5.1 .

If device implementations are capable of being rotated by user (such as automatically via an accelerometer or manually via user input):

  • [C-2-1] The camera preview MUST be mirrored horizontally relative to the device's current orientation.

7.5.3.外接攝影機

設備實現:

  • MAY include support for an external camera that is not necessarily always connected.

If device implementations include support for an external camera, they:

  • [C-1-1] MUST declare the platform feature flag android.hardware.camera.external and android.hardware camera.any .
  • [C-1-2] MUST support USB Video Class (UVC 1.0 or higher) if the external camera connects through the USB port.
  • SHOULD support video compressions such as MJPEG to enable transfer of high-quality unencoded streams (ie raw or independently compressed picture streams).
  • MAY support multiple cameras.
  • MAY support camera-based video encoding. If supported, a simultaneous unencoded / MJPEG stream (QVGA or greater resolution) MUST be accessible to the device implementation.

7.5.4.相機 API 行為

Android includes two API packages to access the camera, the newer android.hardware.camera2 API expose lower-level camera control to the app, including efficient zero-copy burst/streaming flows and per-frame controls of exposure, gain, white balance gains, color conversion, denoising, sharpening, and more.

The older API package, android.hardware.Camera , is marked as deprecated in Android 5.0 but as it should still be available for apps to use. Android device implementations MUST ensure the continued support of the API as described in this section and in the Android SDK.

Device implementations MUST implement the following behaviors for the camera-related APIs, for all available cameras.設備實現:

  • [C-0-1] MUST use android.hardware.PixelFormat.YCbCr_420_SP for preview data provided to application callbacks when an application has never called android.hardware.Camera.Parameters.setPreviewFormat(int) .
  • [C-0-2] MUST further be in the NV21 encoding format when an application registers an android.hardware.Camera.PreviewCallback instance and the system calls the onPreviewFrame() method and the preview format is YCbCr_420_SP, the data in the byte[] passed into onPreviewFrame() .也就是說,NV21必須是預設值。
  • [C-0-3] MUST support the YV12 format (as denoted by the android.graphics.ImageFormat.YV12 constant) for camera previews for both front- and rear-facing cameras for android.hardware.Camera . (The hardware video encoder and camera may use any native pixel format, but the device implementation MUST support conversion to YV12.)
  • [C-0-4] MUST support the android.hardware.ImageFormat.YUV_420_888 and android.hardware.ImageFormat.JPEG formats as outputs through the android.media.ImageReader API for android.hardware.camera2 devices that advertise REQUEST_AVAILABLE_CAPABILITIES_BACKWARD_COMPATIBLE capability in android.request.availableCapabilities .
  • [C-0-5] MUST still implement the full Camera API included in the Android SDK documentation, regardless of whether the device includes hardware autofocus or other capabilities.例如,缺乏自動對焦的攝影機仍然必須呼叫任何已註冊的android.hardware.Camera.AutoFocusCallback實例(即使這與非Autofocus相機無關,請注意)請注意,這確實適用於前面的相機; for instance, even though most front-facing cameras do not support autofocus, the API callbacks must still be “faked” as described.
  • [C-0-6] MUST recognize and honor each parameter name defined as a constant on the android.hardware.Camera.Parameters class. Conversely, device implementations MUST NOT honor or recognize string constants passed to the android.hardware.Camera.setParameters() method other than those documented as constants on the android.hardware.Camera.Parameters .也就是說,如果硬體允許,則必須支援所有標準攝影機參數,並且必須不支援自訂相機參數類型。 For instance, device implementations that support image capture using high dynamic range (HDR) imaging techniques MUST support camera parameter Camera.SCENE_MODE_HDR .
  • [C-0-7] MUST report the proper level of support with the android.info.supportedHardwareLevel property as described in the Android SDK and report the appropriate framework feature flags .
  • [C-0-8] MUST also declare its individual camera capabilities of android.hardware.camera2 via the android.request.availableCapabilities property and declare the appropriate feature flags ; MUST define the feature flag if any of its attached camera devices supports the feature.
  • [C-0-9] MUST broadcast the Camera.ACTION_NEW_PICTURE intent whenever a new picture is taken by the camera and the entry of the picture has been added to the media store.
  • [C-0-10] MUST broadcast the Camera.ACTION_NEW_VIDEO intent whenever a new video is recorded by the camera and the entry of the picture has been added to the media store.

7.5.5。相機方向

If device implementations have a front- or a rear-facing camera, such camera(s):

  • [C-1-1] MUST be oriented so that the long dimension of the camera aligns with the screen's long dimension.也就是說,當設備處於橫向方向時,相機必須以橫向方向捕捉影像。無論設備的自然取向如何,這都適用;也就是說,它適用於景觀主要設備以及肖像主要設備。

7.6。記憶體和儲存

7.6.1.最小內存和存儲

設備實現:

  • [C-0-1] MUST include a Download Manager that applications MAY use to download data files and they MUST be capable of downloading individual files of at least 100MB in size to the default “cache” location.

7.6.2.應用程式共享儲存

設備實現:

  • [C-0-1] MUST offer storage to be shared by applications, also often referred as “shared external storage”, "application shared storage" or by the Linux path "/sdcard" it is mounted on.
  • [C-0-2] 必須配置預設安裝的共享存儲,即“開箱即用”,無論存儲是在內部存儲組件還是可移動存儲介質(例如安全數位卡插槽)上實現)。
  • [C-0-3] MUST mount the application shared storage directly on the Linux path sdcard or include a Linux symbolic link from sdcard to the actual mount point.
  • [C-0-4] MUST enforce the android.permission.WRITE_EXTERNAL_STORAGE permission on this shared storage as documented in the SDK.共享儲存否則必須透過獲得該許可的任何應用程式可寫入。

Device implementations MAY meet the above requirements using either:

  • a user-accessible removable storage, such as a Secure Digital (SD) card slot.
  • a portion of the internal (non-removable) storage as implemented in the Android Open Source Project (AOSP).

If device implementations use removable storage to satisfy the above requirements, they:

  • [C-1-1] MUST implement a toast or pop-up user interface warning the user when there is no storage medium inserted in the slot.
  • [C-1-2] MUST include a FAT-formatted storage medium (eg SD card) or show on the box and other material available at time of purchase that the storage medium has to be purchased separately.

If device implementations use a protion of the non-removable storage to satisfy the above requirements, they:

  • SHOULD use the AOSP implementation of the internal application shared storage.
  • 可與應用程式私有資料共用儲存空間。

If device implementations include multiple shared storage paths (such as both an SD card slot and shared internal storage), they:

  • [C-3-1] MUST allow only pre-installed and privileged Android applications with the WRITE_EXTERNAL_STORAGE permission to write to the secondary external storage, except when writing to their package-specific directories or within the URI returned by firing the ACTION_OPEN_DOCUMENT_TREE intent.

如果裝置實現具有支援 USB 週邊模式的 USB 端口,則:

  • [C-3-1] MUST provide a mechanism to access the data on the application shared storage from a host computer.
  • SHOULD expose content from both storage paths transparently through Android's media scanner service and android.provider.MediaStore .
  • 可以使用 USB 大容量存儲,但應該使用媒體傳輸協定來滿足此要求。

如果裝置實現具有 USB 週邊模式的 USB 連接埠並支援媒體傳輸協議,則它們:

  • 應與參考 Android MTP 主機、 Android 檔案傳輸相容。
  • 應報告 USB 裝置類別 0x00。
  • SHOULD report a USB interface name of 'MTP'.

7.6.3. Adoptable Storage

如果設備不像電視那樣本質上是移動的,則設備實現是:

  • [SR] STRONGLY RECOMMENDED to implement the adoptable storage in a long-term stable location, since accidentally disconnecting them can cause data loss/corruption.

如果可移動儲存裝置連接埠處於長期穩定的位置,例如在電池盒或其他保護蓋內,則裝置實現為:

7.7. USB

If device implementations have a USB port, they:

  • SHOULD support USB peripheral mode and SHOULD support USB host mode.

7.7.1. USB peripheral mode

If device implementations include a USB port supporting peripheral mode:

  • [C-1-1] The port MUST be connectable to a USB host that has a standard type-A or type-C USB port.
  • [C-1-2] MUST report the correct value of iSerialNumber in USB standard device descriptor through android.os.Build.SERIAL .
  • [C-1-3] MUST detect 1.5A and 3.0A chargers per the Type-C resistor standard and MUST detect changes in the advertisement if they support Type-C USB.
  • [SR] The port SHOULD use micro-B, micro-AB or Type-C USB form factor.強烈建議現有和新的 Android 裝置滿足這些要求,以便它們能夠升級到未來的平台版本。
  • [SR] The port SHOULD be located on the bottom of the device (according to natural orientation) or enable software screen rotation for all apps (including home screen), so that the display ws correctly when the home screen the so that the display ws correctly wsen the orm. 。 Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to future platform releases.
  • [SR] SHOULD implement support to draw 1.5 A current during HS chirp and traffic as specified in the USB Battery Charging specification, revision 1.2 .強烈建議現有和新的 Android 裝置滿足這些要求,以便它們能夠升級到未來的平台版本。
  • [SR] STRONGLY RECOMMENDED to not support proprietary charging methods that modify Vbus voltage beyond default levels, or alter sink/source roles as such may result in interoperability issues with the chargers or devices that support the standard USB Power Delivery methods. While this is called out as "STRONGLY RECOMMENDED", in future Android versions we might REQUIRE all type-C devices to support full interoperability with standard type-C chargers.
  • [SR] STRONGLY RECOMMENDED to support Power Delivery for data and power role swapping when they support Type-C USB and USB host mode.
  • SHOULD support Power Delivery for high-voltage charging and support for Alternate Modes such as display out.
  • SHOULD implement the Android Open Accessory (AOA) API and specification as documented in the Android SDK documentation.

If device implementations including a USB port, implement the AOA specification, they:

  • [C-2-1] MUST declare support for the hardware feature android.hardware.usb.accessory .
  • [C-2-2] The USB mass storage class MUST include the string "android" at the end of the interface description iInterface string of the USB mass storage
  • SHOULD NOT implement AOAv2 audio documented in the Android Open Accessory Protocol 2.0 documentation. AOAv2 audio is deprecated as of Android version 8.0 (API level 26).

7.7.2. USB host mode

If device implementations include a USB port supporting host mode, they:

  • [C-1-1] MUST implement the Android USB host API as documented in the Android SDK and MUST declare support for the hardware feature android.hardware.usb.host .
  • [C-1-2] MUST implement support to connect standard USB peripherals, in other words, they MUST either:
    • Have an on-device type C port or ship with cable(s) adapting an on-device proprietary port to a standard USB type-C port (USB Type-C device).
    • Have an on-device type A or ship with cable(s) adapting an on-device proprietary port to a standard USB type-A port.
    • Have an on-device micro-AB port, which SHOULD ship with a cable adapting to a standard type-A port.
  • [C-1-3] MUST NOT ship with an adapter converting from USB type A or micro-AB ports to a type-C port (receptacle).
  • [SR] STRONGLY RECOMMENDED to implement the USB audio class as documented in the Android SDK documentation.
  • SHOULD support charging the connected USB peripheral device while in host mode; advertising a source current of at least 1.5A as specified in the Termination Parameters section of the USB Type-C Cable and Connector Specification Revision 1.2 for USB Type-C connectors or using Charging Downstream Port(CDP) output current range as specified in the USB Battery Charging specifications, revision 1.2 for Micro-AB connectors.
  • SHOULD implement and support USB Type-C standards.

If device implementations include a USB port supporting host mode and the USB audio class, they:

  • [C-2-1] MUST support the USB HID class
  • [C-2-2] MUST support the detection and mapping of the following HID data fields specified in the USB HID Usage Tables and the Voice Command Usage Request to the KeyEvent constants as below:
    • Usage Page (0xC) Usage ID (0x0CD): KEYCODE_MEDIA_PLAY_PAUSE
    • Usage Page (0xC) Usage ID (0x0E9): KEYCODE_VOLUME_UP
    • Usage Page (0xC) Usage ID (0x0EA): KEYCODE_VOLUME_DOWN
    • Usage Page (0xC) Usage ID (0x0CF): KEYCODE_VOICE_ASSIST

If device implementations include a USB port supporting host mode and the Storage Access Framework (SAF), they:

  • [C-3-1] MUST recognize any remotely connected MTP (Media Transfer Protocol) devices and make their contents accessible through the ACTION_GET_CONTENT , ACTION_OPEN_DOCUMENT , and ACTION_CREATE_DOCUMENT intents. 。

If device implementations include a USB port supporting host mode and USB Type-C, they:

  • [C-4-1] MUST implement Dual Role Port functionality as defined by the USB Type-C specification (section 4.5.1.3.3).
  • [SR] STRONGLY RECOMMENDED to support DisplayPort, SHOULD support USB SuperSpeed Data Rates, and are STRONGLY RECOMMENDED to support Power Delivery for data and power role swapping.
  • [SR] STRONGLY RECOMMENDED to NOT support Audio Adapter Accessory Mode as described in the Appendix A of the USB Type-C Cable and Connector Specification Revision 1.2 .
  • SHOULD implement the Try.* model that is most appropriate for the device form factor. For example a handheld device SHOULD implement the Try.SNK model.

7.8。聲音的

7.8.1.麥克風

If device implementations include a microphone, they:

  • [C-1-1] MUST report the android.hardware.microphone feature constant.
  • [C-1-2] MUST meet the audio recording requirements in section 5.4 .
  • [C-1-3] MUST meet the audio latency requirements in section 5.6 .
  • [SR] STRONGLY RECOMMENDED to support near-ultrasound recording as described in section 7.8.3 .

If device implementations omit a microphone, they:

  • [C-2-1] MUST NOT report the android.hardware.microphone feature constant.
  • [C-2-2] MUST implement the audio recording API at least as no-ops, per section 7 .

7.8.2.音訊輸出

If device implementations include a speaker or an audio/multimedia output port for an audio output peripheral such as a 4 conductor 3.5mm audio jack or USB host mode port using USB audio class , they:

  • [C-1-1] MUST report the android.hardware.audio.output feature constant.
  • [C-1-2] MUST meet the audio playback requirements in section 5.5 .
  • [C-1-3] MUST meet the audio latency requirements in section 5.6 .
  • [SR] STRONGLY RECOMMENDED to support near-ultrasound playback as described in section 7.8.3 .

If device implementations do not include a speaker or audio output port, they:

  • [C-2-1] MUST NOT report the android.hardware.audio.output feature.
  • [C-2-2] MUST implement the Audio Output related APIs as no-ops at least.

For the purposes of this section, an "output port" is a physical interface such as a 3.5mm audio jack, HDMI, or USB host mode port with USB audio class. Support for audio output over radio-based protocols such as Bluetooth, WiFi, or cellular network does not qualify as including an "output port".

7.8.2.1. Analog Audio Ports

In order to be compatible with the headsets and other audio accessories using the 3.5mm audio plug across the Android ecosystem, if a device implementation includes one or more analog audio ports, at least one of the 達羅 port(dctor) port abe a condube 4m)( 3.5 公釐音訊插孔。

If device implementations have a 4 conductor 3.5mm audio jack, they:

  • [C-1-1] MUST support audio playback to stereo headphones and stereo headsets with a microphone.
  • [C-1-2] MUST support TRRS audio plugs with the CTIA pin-out order.
  • [C-1-3] MUST support the detection and mapping to the keycodes for the following 3 ranges of equivalent impedance between the microphone and ground conductors on the audio plug:
    • 70 ohm or less : KEYCODE_HEADSETHOOK
    • 210-290 ohm : KEYCODE_VOLUME_UP
    • 360-680 ohm : KEYCODE_VOLUME_DOWN
  • [C-1-4] MUST trigger ACTION_HEADSET_PLUG upon a plug insert, but only after all contacts on plug are touching their relevant segments on the jack.
  • [C-1-5] MUST be capable of driving at least 150mV ± 10% of output voltage on a 32 ohm speaker impedance.
  • [C-1-6] MUST have a microphone bias voltage between 1.8V ~ 2.9V.
  • [SR] STRONGLY RECOMMENDED to detect and map to the keycode for the following range of equivalent impedance between the microphone and ground conductors on the audio plug:
    • 110-180 ohm: KEYCODE_VOICE_ASSIST
  • SHOULD support audio plugs with the OMTP pin-out order.
  • SHOULD support audio recording from stereo headsets with a microphone.

If device implementations have a 4 conductor 3.5mm audio jack and support a microphone, and broadcast the android.intent.action.HEADSET_PLUG with the extra value microphone set as 1, they:

  • [C-2-1] 必須支援偵測插入的音訊配件上的麥克風。

7.8.3。近超音波

近超音波音訊的頻段為 18.5 kHz 至 20 kHz。

設備實現:

If PROPERTY_SUPPORT_MIC_NEAR_ULTRASOUND is "true", the following requirements MUST be met by the VOICE_RECOGNITION and UNPROCESSED audio sources:

  • [C-1-1] 麥克風在 18.5 kHz 至 20 kHz 頻段的平均功率響應不得比 2 kHz 頻段的響應低 15 dB 以上。
  • [C-1-2] 對於 -26 dBFS 的 19 kHz 音調,麥克風在 18.5 kHz 至 20 kHz 範圍內的未加權信噪比必須不低於 50 dB。

If PROPERTY_SUPPORT_SPEAKER_NEAR_ULTRASOUND is "true":

  • [C-2-1] 揚聲器在 18.5 kHz - 20 kHz 範圍內的平均響應必須比 2 kHz 範圍內的響應低不少於 40 dB。

7.9。虛擬實境

Android 包含用於建立「虛擬實境」(VR) 應用程式(包括高品質行動 VR 體驗)的 API 和工具。設備實作必須正確實作這些 API 和行為,如本節所述。

7.9.1.虛擬實境模式

Android 支援VR 模式,可在 VR 應用程式具有使用者焦點時處理通知的立體渲染並停用單眼系統 UI 元件。

7.9.2. Virtual Reality High Performance

If device implementations identify the support of high performance VR for longer user periods through the android.hardware.vr.high_performance feature flag, they:

  • [C-1-1] 必須至少有 2 個物理核心。
  • [C-1-2] MUST declare android.software.vr.mode feature .
  • [C-1-3] 必須支援持續性能模式。
  • [C-1-4] 必須支援 OpenGL ES 3.2。
  • [C-1-5] MUST support Vulkan Hardware Level 0 and SHOULD support Vulkan Hardware Level 1.
  • [C-1-6] MUST implement EGL_KHR_mutable_render_buffer , EGL_ANDROID_front_buffer_auto_refresh , EGL_ANDROID_get_native_client_buffer , EGL_KHR_fence_sync , EGL_KHR_wait_sync , EGL_IMG_context_priority , EGL_EXT_protected_content , and expose the extensions in the list of available EGL extensions.
  • [C-1-7] GPU 和顯示器必須能夠同步對共享前端緩衝區的訪問,以便在兩個渲染上下文中以60fps 的速度進行VR 內容的交替眼渲染,並且不會出現明顯的撕裂偽像。
  • [C-1-8] MUST implement GL_EXT_multisampled_render_to_texture , GL_OVR_multiview , GL_OVR_multiview2 , GL_OVR_multiview_multisampled_render_to_texture , GL_EXT_protected_textures , GL_EXT_EGL_image_array , GL_EXT_external_buffer , and expose the extensions in the list of available GL extensions.
  • [C-1-9] MUST implement support for AHardwareBuffer flags AHARDWAREBUFFER_USAGE_GPU_DATA_BUFFER and AHARDWAREBUFFER_USAGE_SENSOR_DIRECT_DATA as described in the NDK.
  • [C-1-10] MUST implement support for AHardwareBuffers with more than one layer.
  • [C-1-11] MUST support H.264 decoding at least 3840x2160@30fps-40Mbps (equivalent to 4 instances of 1920x1080@30fps-10Mbps or 2 instances of 1920x1080@60fps-20Mbps).
  • [C-1-12] MUST support HEVC and VP9, MUST be capable to decode at least 1920x1080@30fps-10Mbps and SHOULD be capable to decode 3840x2160@30fps-20Mbps (equivalent to 4 instances of 1920x1080@30fps-5Mbps).
  • [C-1-13] MUST support HardwarePropertiesManager.getDeviceTemperatures API and return accurate values for skin temperature.
  • [C-1-14] MUST have an embedded screen, and its resolution MUST be at least be FullHD(1080p) and STRONGLY RECOMMENDED TO BE be QuadHD (1440p) or higher.
  • [C-1-15] 在 VR 模式下,顯示器的更新頻率必須至少為 60 Hz。
  • [C-1-16] The display latency (as measured on Gray-to-Gray, White-to-Black, and Black-to-White switching time) MUST be ≤ 6 milliseconds.
  • [C-1-17] 顯示器必須支援餘輝時間≤ 5 毫秒的低餘輝模式,餘輝定義為像素發光的時間量。
  • [C-1-18] MUST support Bluetooth 4.2 and Bluetooth LE Data Length Extension section 7.4.3 .
  • [C-1-19] MUST support and properly report Direct Channel Type for all of the following default sensor types:
    • TYPE_ACCELEROMETER
    • TYPE_ACCELEROMETER_UNCALIBRATED
    • TYPE_GYROSCOPE
    • TYPE_GYROSCOPE_UNCALIBRATED
    • TYPE_MAGNETIC_FIELD
    • TYPE_MAGNETIC_FIELD_UNCALIBRATED
  • [C-1-20] MUST support the TYPE_HARDWARE_BUFFER direct channel type for all Direct Channel Types listed above.
  • [SR] Are STRONGLY RECOMMENDED to support android.hardware.sensor.hifi_sensors feature and MUST meet the gyroscope, accelerometer, and magnetometer related requirements for android.hardware.hifi_sensors .
  • MAY provide an exclusive core to the foreground application and MAY support the Process.getExclusiveCores API to return the numbers of the cpu cores that are exclusive to the top foreground application. If exclusive core is supported then the core MUST not allow any other userspace processes to run on it (except device drivers used by the application), but MAY allow some kernel processes to run as necessary.

8. 性能和功率

Some minimum performance and power criteria are critical to the user experience and impact the baseline assumptions developers would have when developing an app.

8.1.使用者體驗一致性

A smooth user interface can be provided to the end user if there are certain minimum requirements to ensure a consistent frame rate and response times for applications and games. Device implementations, depending on the device type, MAY have measurable requirements for the user interface latency and task switching as described in section 2 .

8.2.文件 I/O 存取效能

Providing a common baseline for a consistent file access performance on the application private data storage ( /data partition) allows app developers to set a proper expectation that would help their software design. Device implementations, depending on the device type, MAY have certain requirements described in section 2 for the following read and write operations:

  • Sequential write performance . Measured by writing a 256MB file using 10MB write buffer.
  • Random write performance . Measured by writing a 256MB file using 4KB write buffer.
  • Sequential read performance . Measured by reading a 256MB file using 10MB write buffer.
  • Random read performance . Measured by reading a 256MB file using 4KB write buffer.

8.3.省電模式

Android includes App Standby and Doze power-saving modes to optimize battery usage. [SR] All Apps exempted from these modes are STRONGLY RECOMMENDED to be made visible to the end user. [SR] The triggering, maintenance, wakeup algorithms and the use of global system settings of these power-saving modes are STRONGLY RECOMMENDED NOT to deviate from the Android Open Source Project.

In addition to the power-saving modes, Android device implementations MAY implement any or all of the 4 sleeping power states as defined by the Advanced Configuration and Power Interface (ACPI).

If device implementations implements S3 and S4 power states as defined by the ACPI, they:

  • [C-1-1] MUST only enter these states when closing a lid that is physically part of the device.

8.4.用電核算

A more accurate accounting and reporting of the power consumption provides the app developer both the incentives and the tools to optimize the power usage pattern of the application.

設備實現:

  • [SR] STRONGLY RECOMMENDED to provide a per-component power profile that defines the current consumption value for each hardware component and the approximate battery drain caused by the components over time as documented in the Android Open Source Project site.
  • [SR] STRONGLY RECOMMENDED to report all power consumption values in milliampere hours (mAh).
  • [SR] STRONGLY RECOMMENDED to report CPU power consumption per each process's UID. The Android Open Source Project meets the requirement through the uid_cputime kernel module implementation.
  • [SR] STRONGLY RECOMMENDED to make this power usage available via the adb shell dumpsys batterystats shell command to the app developer.
  • SHOULD be attributed to the hardware component itself if unable to attribute hardware component power usage to an application.

8.5。一致的性能

Performance can fluctuate dramatically for high-performance long-running apps, either because of the other apps running in the background or the CPU throttling due to temperature limits. Android includes programmatic interfaces so that when the device is capable, the top foreground application can request that the system optimize the allocation of the resources to address such fluctuations.

設備實現:

如果設備實現報告支援持續性能模式,則它們:

  • [C-1-1] 必須在頂級前台應用請求時為該應用程式提供至少 30 分鐘一致的效能等級。
  • [C-1-2] MUST honor the Window.setSustainedPerformanceMode() API and other related APIs.

如果設備實作包括兩個或更多 CPU 內核,則:

  • 應提供至少一個可由頂級前台應用程式保留的獨佔核心。

如果裝置實作支援為頂級前台應用程式保留一個獨佔核心,則它們:

  • [C-2-1] MUST report through the Process.getExclusiveCores() API method the ID numbers of the exclusive cores that can be reserved by the top foreground application.
  • [C-2-2] 不得允許除應用程式使用的裝置驅動程式之外的任何用戶空間進程在獨佔核心上運行,但可以允許某些核心進程根據需要運行。

如果設備實作不支援獨佔核心,則:

9. 安全模型相容性

設備實現:

  • [C-0-1] 必須實作與 Android 開發者文件 API 中的安全性和權限參考文件中定義的 Android 平台安全模型一致的安全模型。

  • [C-0-2] 必須支援安裝自簽名應用程序,無需任何第三方/機構提供任何額外的權限/憑證。 Specifically, compatible devices MUST support the security mechanisms described in the follow subsections.

9.1.權限

設備實現:

  • [C-0-1] MUST support the Android permissions model as defined in the Android developer documentation. Specifically, they MUST enforce each permission defined as described in the SDK documentation;無法省略,更改或忽略權限。

  • MAY add additional permissions, provided the new permission ID strings are not in the android.\* namespace.

  • [C-0-2] Permissions with a protectionLevel of PROTECTION_FLAG_PRIVILEGED MUST only be granted to apps preloaded in the privileged path(s) of the system image and within the subset of the explicitly allowlisted permissions for each app. The AOSP implementation meets this requirement by reading and honoring the allowlisted permissions for each app from the files in the etc/permissions/ path and using the system/priv-app path as the privileged path.

保護等級為危險的權限是運行時權限。 Applications with targetSdkVersion > 22 request them at runtime.

設備實現:

  • [C-0-3] 必須顯示專用介面,供使用者決定是否授予所要求的執行時間權限,並提供一個介面供使用者管理執行時間權限。
  • [C-0-4] 兩個使用者介面必須有且只有一種實作。
  • [C-0-5] MUST NOT grant any runtime permissions to preinstalled apps unless:
  • the user's consent can be obtained before the application uses it
  • the runtime permissions are associated with an intent pattern for which the preinstalled application is set as the default handler

如果設備實現包括預先安裝的應用程式或希望允許第三方應用程式存取使用情況統計信息,則:

  • [C-1-1] are STRONGLY RECOMMENDED provide user-accessible mechanism to grant or revoke access to the usage stats in response to the android.settings.ACTION_USAGE_ACCESS_SETTINGS intent for apps that declare the android.permission.PACKAGE_USAGE_STATS permission.

如果設備實現打算禁止任何應用程式(包括預先安裝的應用程式)存取使用情況統計訊息,則:

  • [C-2-1] MUST still have an activity that handles the android.settings.ACTION_USAGE_ACCESS_SETTINGS intent pattern but MUST implement it as a no-op, that is to have an equivalent behavior as when the user is declined for access.

9.2. UID 和進程隔離

設備實現:

  • [C-0-1] 必須支援 Android 應用程式沙盒模型,其中每個應用程式都作為唯一的 Unixstyle UID 並在單獨的進程中運行。
  • [C-0-2] 必須支援以同一 Linux 用戶 ID 運行多個應用程序,前提是這些應用程式按照安全性和權限參考中的定義進行了正確簽名和建置。

9.3.檔案系統權限

設備實現:

9.4.備用執行環境

裝置實作必須保持 Android 安全性和權限模型的一致性,即使它們包括使用 Dalvik 可執行格式或本機程式碼以外的其他軟體或技術執行應用程式的執行時間環境。換句話說:

  • [C-0-1] 備用運行時本身必須是 Android 應用,並且遵守標準 Android 安全模型,如第 9 節其他地方所述。

  • [C-0-2] Alternate runtimes MUST NOT be granted access to resources protected by permissions not requested in the runtime's AndroidManifest.xml file via the < uses-permission > mechanism.

  • [C-0-3] 備用運行時不得允許應用程式使用受僅限於系統應用的 Android 權限保護的功能。

  • [C-0-4] 備用運行時必須遵守Android 沙盒模型,並且使用備用運行時安裝的應用程式不得重複使用裝置上安裝的任何其他應用程式的沙盒,除非透過共享用戶ID 和簽署證書的標準Android機制。

  • [C-0-5] 備用運行時不得與其他 Android 應用程式對應的沙箱一起啟動、授予或被授予存取權限。

  • [C-0-6] 備用運行時不得使用超級使用者 (root) 或任何其他使用者 ID 的任何權限來啟動、不得被授予或向其他應用程式授予任何權限。

  • [C-0-7] When the .apk files of alternate runtimes are included in the system image of device implementations, it MUST be signed with a key distinct from the key used to sign other applications included with the device implementations.

  • [C-0-8] 安裝應用程式時,備用運行時必須取得使用者對應用程式使用的 Android 權限的同意。

  • [C-0-9] 當應用程式需要使用具有相應 Android 權限的裝置資源(例如相機、GPS 等)時,備用運行時必須通知使用者該應用程式將能夠存取該資源。

  • [C-0-10] 當運行時環境不以這種方式記錄應用程式功能時,運行時環境必須在使用該運行時安裝任何應用程式時列出該運行時本身擁有的所有權限。

  • Alternate runtimes SHOULD install apps via the PackageManager into separate Android sandboxes (Linux user IDs, etc.).

  • 備用運行時可以提供一個由所有使用備用運行時的應用程式共享的 Android 沙箱。

9.5。多用戶支援

Android includes support for multiple users and provides support for full user isolation.

  • 如果裝置實作使用可移動媒體作為主要外部存儲,則裝置實作可以但不應該啟用多使用者。

If device implementations include multiple users, they:

  • [C-1-1] MUST meet the following requirements related to multi-user support .
  • [C-1-2] 必須為每個使用者實作與 API 中的安全性和權限參考文件中定義的 Android 平台安全模型一致的安全模型。
  • [C-1-3] MUST have separate and isolated shared application storage (aka /sdcard ) directories for each user instance.
  • [C-1-4] 必須確保給定用戶擁有並代表給定用戶運行的應用程式無法列出、讀取或寫入任何其他用戶擁有的文件,即使兩個用戶的資料儲存在同一卷或文件系統。
  • [C-1-5] 如果裝置實作使用可移動媒體作為外部儲存API,則在啟用多用戶時,必須使用僅儲存在只能由系統存取的不可移動媒體上的金鑰來加密SD 卡的內容。由於這將使主機 PC 無法讀取介質,因此設備實作將需要切換到 MTP 或類似系統,以便主機 PC 能夠存取目前使用者的資料。

If device implementations include multiple users and do not declare the android.hardware.telephony feature flag, they:

  • [C-2-1] MUST support restricted profiles, a feature that allows device owners to manage additional users and their capabilities on the device.透過受限設定文件,裝置擁有者可以快速設定單獨的環境供其他使用者工作,並能夠管理這些環境中可用的應用程式中的更細粒度的限制。

If device implementations include multiple users and declare the android.hardware.telephony feature flag, they:

  • [C-3-1] MUST NOT support restricted profiles but MUST align with the AOSP implementation of controls to enable /disable other users from accessing the voice calls and SMS.

9.6.高級簡訊警告

Android 支援警告用戶任何傳出的進階 SMS 訊息。付費 SMS 訊息是發送到向運營商註冊的服務的文字訊息,可能會向用戶收取費用。

If device implementations declare support for android.hardware.telephony , they:

  • [C-1-1] MUST warn users before sending a SMS message to numbers identified by regular expressions defined in /data/misc/sms/codes.xml file in the device.上游Android開源專案提供了滿足此要求的實作。

9.7. Kernel Security Features

Android 沙箱包括使用安全增強型 Linux (SELinux) 強制存取控制 (MAC) 系統、seccomp 沙箱以及 Linux 核心中其他安全功能的功能。設備實現:

  • [C-0-1] MUST maintain compatibility with existing applications, even when SELinux or any other security features are implemented below the Android framework.
  • [C-0-2] MUST NOT have a visible user interface when a security violation is detected and successfully blocked by the security feature implemented below the Android fr時開發。
  • [C-0-3] 不得讓 SELinux 或在 Android 框架下實現的任何其他安全功能可供使用者或應用程式開發者設定。
  • [C-0-4] MUST NOT allow an application that can affect another application through an API (such as a Device Administration API) to configure a policy that breaks compatibility.
  • [C-0-5] 必須將媒體框架拆分為多個進程,以便可以更嚴格地授予每個進程的存取權限,如 Android 開源專案網站中所述
  • [C-0-6] MUST implement a kernel application sandboxing mechanism which allows filtering of system calls using a configurable policy from multithreaded programs.上游 Android 開源專案透過啟用具有線程組同步 (TSYNC) 的 seccomp-BPF 來滿足此要求,如source.android.com 的核心配置部分所述。

核心完整性和自我保護功能是 Android 安全不可或缺的一部分。設備實現:

  • [C-0-7] MUST implement kernel stack buffer overflow protections (eg CONFIG_CC_STACKPROTECTOR_STRONG ).
  • [C-0-8] MUST implement strict kernel memory protections where executable code is read-only, read-only data is non-executable and non-writable, and writable data is non-executable (eg CONFIG_DEBUG_RODATA or CONFIG_STRICT_KERNEL_RWX ).
  • [SR] STRONGLY RECOMMENDED to keep kernel data which is written only during initialization marked read-only after initialization (eg __ro_after_init ).
  • [SR} STRONGLY RECOMMENDED to implement static and dynamic object size bounds checking of copies between user-space and kernel-space (eg CONFIG_HARDENED_USERCOPY ).
  • [SR] STRONGLY RECOMMENDED to never execute user-space memory when running in the kernel (eg hardware PXN, or emulated via CONFIG_CPU_SW_DOMAIN_PAN or CONFIG_ARM64_SW_TTBR0_PAN ).
  • [SR] STRONGLY RECOMMENDED to never read or write user-space memory in the kernel outside of normal usercopy access APIs (eg hardware PAN, or emulated via CONFIG_CPU_SW_DOMAIN_PAN or CONFIG_ARM64_SW_TTBR0_PAN ).
  • [SR] STRONGLY RECOMMENDED to randomize the layout of the kernel code and memory, and to avoid exposures that would compromise the randomization (eg CONFIG_RANDOMIZE_BASE with bootloader entropy via the /chosen/kaslr-seed Device Tree node or EFI_RNG_PROTOCOL ).

If device implementations use a Linux kernel, they:

  • [C-1-1] MUST implement SELinux.
  • [C-1-2] MUST set SELinux to global enforcing mode.
  • [C-1-3] MUST configure all domains in enforcing mode. No permissive mode domains are allowed, including domains specific to a device/vendor.
  • [C-1-4] MUST NOT modify, omit, or replace the neverallow rules present within the system/sepolicy folder provided in the upstream Android Open Source Project (AOSP) and the policy MUST compile with all neverallow rules present, for both AOSP SELinux domains as well as device/vendor specific domains.
  • SHOULD retain the default SELinux policy provided in the system/sepolicy folder of the upstream Android Open Source Project and only further add to this policy for their own device-specific configuration.

If device implementations use kernel other than Linux, they:

  • [C-2-1] MUST use an mandatory access control system that is equivalent to SELinux.

9.8.隱私

9.8.1.使用歷史

Android 儲存使用者選擇的歷史記錄,並透過UsageStatsManager管理此類歷史記錄。

設備實現:

  • [C-1-1] MUST keep a reasonable retention period of such user history.
  • [SR] Are STRONGLY RECOMMENDED to keep the 14 days retention period as configured by default in the AOSP implementation.

9.8.2.記錄

If device implementations include functionality in the system that captures the contents displayed on the screen and/or records the audio stream played on the device, they:

  • [C-1-1] 每當啟用此功能並主動捕捉/錄製時,都必須持續向使用者發出通知。

If device implementations include a component enabled out-of-box, capable of recording ambient audio to infer useful information about user's context, they:

  • [C-2-1] 除非獲得使用者明確同意,否則不得將錄製的原始音訊或任何可轉換回原始音訊或近似傳真的格式儲存在裝置上的持久儲存中或從裝置傳輸出去。

9.8.3.連接性

如果裝置實現具有支援 USB 週邊模式的 USB 端口,則:

  • [C-1-1] 必須提供一個使用者介面,在允許透過 USB 連接埠存取共用儲存的內容之前徵求使用者的同意。

9.8.4。網路流量

設備實現:

  • [C-0-1] 必須為系統信任的憑證授權單位 (CA) 儲存區預先安裝與上游 Android 開源專案中提供的相同的根憑證。
  • [C-0-2] 必須附帶空的用戶根 CA 儲存。
  • [C-0-3] 當新增用戶根 CA 時,必須向使用者顯示警告,指示網路流量可能受到監控。

如果設備流量透過 VPN 路由,設備實現:

  • [C-1-1] 必須向使用者顯示警告,指示:
    • 該網路流量可能會受到監控。
    • 此網路流量透過提供 VPN 的特定 VPN 應用程式進行路由。

If device implementations have a mechanism, enabled out-of-box by default, that routes network data traffic through a proxy server or VPN gateway (for example, preloading a VPN service with android.permission.CONTROL_VPN granted), they:

  • [C-2-1] MUST ask for the user's consent before enabling that mechanism, unless that VPN is enabled by the Device Policy Controller via the DevicePolicyManager.setAlwaysOnVpnPackage() , in which case the user does not need to provide a separate consent, but MUST only be notified.

如果裝置實作允許使用者切換第 3 方 VPN 應用程式的「始終在線 VPN」功能,則它們:

  • [C-3-1] MUST disable this user affordance for apps that do not support always-on VPN service in the AndroidManifest.xml file via setting the SERVICE_META_DATA_SUPPORTS_ALWAYS_ON attribute to false .

9.9.資料儲存加密

If device implementations support a secure lock screen as described in section 9.11.1 , they:

  • [C-1-1] MUST support data storage encryption of the application private data ( /data partition ), as well as the application shared storage partition ( /sdcard partition ) if it is a permanent, non-removable part of the device.

If device implementations support a secure lock screen as described in section 9.11.1 and support data storage encryption with Advanced Encryption Standard (AES) crypto performance above 50MiB/sec, they:

  • [C-2-1] MUST enable the data storage encryption by default at the time the user has completed the out-of-box setup experience. If device implementations are already launched on an earlier Android version with encryption disabled by default, such a device cannot meet the requirement through a system software update and thus MAY be exempted.

  • SHOULD meet the above data storage encryption requirement via implementing File Based Encryption (FBE).

9.9.1.直接啟動

設備實現:

9.9.2.基於文件的加密

If device implementations support FBE, they:

  • [C-1-1] 啟動時必須不向使用者詢問憑證,並允許支援直接啟動的應用程式在廣播ACTION_LOCKED_BOOT_COMPLETED訊息後存取裝置加密 (DE) 儲存。
  • [C-1-2] 必須僅在使用者透過提供憑證(例如密碼、PIN、圖案或指紋)解鎖裝置並廣播ACTION_USER_UNLOCKED訊息後才允許存取憑證加密 (CE) 儲存。
  • [C-1-3] MUST NOT offer any method to unlock the CE protected storage without the user-supplied credentials.
  • [C-1-4] MUST support Verified Boot and ensure that DE keys are cryptographically bound to the device's hardware root of trust.
  • [C-1-5] MUST support encrypting file contents using AES with a key length of 256-bits in XTS mode.
  • [C-1-6] MUST support encrypting file name using AES with a key length of 256-bits in CBC-CTS mode.

  • The keys protecting CE and DE storage areas:

  • [C-1-7] 必須以加密方式綁定到硬體支援的金鑰庫。

  • [C-1-8] CE keys MUST be bound to a user's lock screen credentials.
  • [C-1-9] CE keys MUST be bound to a default passcode when the user has not specified lock screen credentials.
  • [C-1-10] 必須是唯一且獨特的,換句話說,任何使用者的 CE 或 DE 金鑰都不能與任何其他使用者的 CE 或 DE 金鑰相符。

  • SHOULD make preloaded essential apps (eg Alarm, Phone, Messenger) Direct Boot aware.

  • MAY support alternative ciphers, key lengths and modes for file content and file name encryption, but MUST use the mandatorily supported ciphers, key lengths and modes by default.

The upstream Android Open Source project provides a preferred implementation of this feature based on the Linux kernel ext4 encryption feature.

9.9.3。全碟加密

If device implementations support full disk encryption (FDE), they:

  • [C-1-1] MUST use AES with a key of 128-bits (or greater) and a mode designed for storage (for example, AES-XTS, AES-CBC-ESSIV).
  • [C-1-2] MUST use a default passcode to wrap the encryption key and MUST NOT write the encryption key to storage at any time without being encrypted.
  • [C-1-3] MUST AES encrypt the encryption key by default unless the user explicitly opts out, except when it is in active use, with the lock screen credentials stretched using a slow stretching algorithm (eg PBKDF2 or scrypt).
  • [C-1-4] The above default password stretching algorithm MUST be cryptographically bound to that keystore when the user has not specified a lock screen credentials or has disabled use of the passcode for encryption and the device provides a hardware-backed keystore.
  • [C-1-5] MUST NOT send encryption key off the device (even when wrapped with the user passcode and/or hardware bound key).

The upstream Android Open Source project provides a preferred implementation of this feature, based on the Linux kernel feature dm-crypt.

9.10。設備完整性

The following requirements ensures there is transparency to the status of the device integrity.設備實現:

  • [C-0-1] MUST correctly report through the System API method PersistentDataBlockManager.getFlashLockState() whether their bootloader state permits flashing of the system image. The FLASH_LOCK_UNKNOWN state is reserved for device implementations upgrading from an earlier version of Android where this new system API method did not exist.

Verified boot is a feature that guarantees the integrity of the device software. If a device implementation supports the feature, it:

  • [C-1-1] MUST declare the platform feature flag android.software.verified_boot .
  • [C-1-2] MUST perform verification on every boot sequence.
  • [C-1-3] MUST start verification from an immutable hardware key that is the root of trust and go all the way up to the system partition.
  • [C-1-4] MUST implement each stage of verification to check the integrity and authenticity of all the bytes in the next stage before executing the code in the next stage.
  • [C-1-5] MUST use verification algorithms as strong as current recommendations from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048).
  • [C-1-6] MUST NOT allow boot to complete when system verification fails, unless the user consents to attempt booting anyway, in which case the data from any non-verified storage blocks MUST not be used.
  • [C-1-7] MUST NOT allow verified partitions on the device to be modified unless the user has explicitly unlocked the boot loader.
  • [SR] If there are multiple discrete chips in the device (eg radio, specialized image processor), the boot process of each of those chips is STRONGLY RECOMMENDED to verify every stage upon booting.
  • [SR] STRONGLY RECOMMENDED to use tamper-evident storage: for when the bootloader is unlocked. Tamper-evident storage means that the boot loader can detect if the storage has been tampered with from inside the HLOS (High Level Operating System).
  • [SR] STRONGLY RECOMMENDED to prompt the user, while using the device, and require physical confirmation before allowing a transition from boot loader locked mode to boot loader unlocked mode.
  • [SR] STRONGLY RECOMMENDED to implement rollback protection for the HLOS (eg boot, system partitions) and to use tamper-evident storage for storing the metadata used for determining the minimum allowable OS version.
  • SHOULD implement rollback protection for any component with persistent firmware (eg modem, camera) and SHOULD use tamper-evident storage for storing the metadata used for determining the minimum allowable version.

The upstream Android Open Source Project provides a preferred implementation of this feature in the external/avb/ repository, which can be integrated into the boot loader used for loading Android.

If device implementations report the feature flag android.hardware.ram.normal , they:

  • [C-2-1] MUST support verified boot for device integrity.

If a device implementation is already launched without supporting verified boot on an earlier version of Android, such a device can not add support for this feature with a system software update and thus are exempted from the requirement.

9.11.金鑰和憑證

The Android Keystore System allows app developers to store cryptographic keys in a container and use them in cryptographic operations through the KeyChain API or the Keystore API .設備實現:

  • [C-0-1] MUST at least allow more than 8,192 keys to be imported.
  • [C-0-2] The lock screen authentication MUST rate-limit attempts and MUST have an exponential backoff algorithm. Beyond 150 failed attempts, the delay MUST be at least 24 hours per attempt.
  • SHOULD not limit the number of keys that can be generated

When the device implementation supports a secure lock screen, it:

  • [C-1-1] MUST back up the keystore implementation with secure hardware.
  • [C-1-2] MUST have implementations of RSA, AES, ECDSA and HMAC cryptographic algorithms and MD5, SHA1, and SHA-2 family hash functions to properly support the Android Keystore system's supported algorithms in an area that is securely isolated from the code running on the kernel and above.安全隔離必須阻止核心或使用者空間程式碼可能存取隔離環境的內部狀態的所有潛在機制,包括 DMA。上游 Android 開源專案 (AOSP) 透過使用Trusty實作來滿足此要求,但另一個基於 ARM TrustZone 的解決方案或第三方審查的基於適當管理程序的隔離的安全實作是替代選項。
  • [C-1-3] MUST perform the lock screen authentication in the isolated execution environment and only when successful, allow the authentication-bound keys to be used.鎖定螢幕憑證的儲存方式必須僅允許隔離的執行環境執行鎖定螢幕身份驗證。上游Android開源專案提供了Gatekeeper硬體抽象層(HAL)和Trusty,可以用來滿足這個需求。
  • [C-1-4] MUST support key attestation where the attestation signing key is protected by secure hardware and signing is performed in secure hardware.證明簽章金鑰必須在足夠多的裝置之間共用,以防止金鑰被用作裝置識別碼。滿足此要求的一種方法是共享相同的證明金鑰,除非給定 SKU 的生產量至少為 100,000 件。如果生產的 SKU 超過 100,000 個單位,則每 100,000 個單位可以使用不同的金鑰。

Note that if a device implementation is already launched on an earlier Android version, such a device is exempted from the requirement to have a hardware-backed keystore, unless it declares the android.hardware.fingerprint feature which requires a hardware-backed keystore.

9.11.1。 Secure Lock Screen

If device implementations have a secure lock screen and include one or more trust agent, which implements the TrustAgentService System API, then they:

  • [C-1-1] MUST indicate the user in the Settings and Lock screen user interface of situations where either the screen auto-lock is deferred or the screen lock can be unlocked by the trust agent. The AOSP meets the requirement by showing a text description for the "Automatically lock setting" and "Power button instantly locks setting" menus and a distinguishable icon on the lock screen.
  • [C-1-2] MUST respect and fully implement all trust agent APIs in the DevicePolicyManager class, such as the KEYGUARD_DISABLE_TRUST_AGENTS constant.
  • [C-1-3] MUST NOT fully implement the TrustAgentService.addEscrowToken() function on a device that is used as the primary personal device (eg handheld) but MAY fully implement the function on device implementations typically shared.
  • [C-1-4] MUST encrypt the tokens added by TrustAgentService.addEscrowToken() before storing them on the device.
  • [C-1-5] MUST NOT store the encryption key on the device.
  • [C-1-6] MUST inform the user about the security implications before enabling the escrow token to decrypt the data storage.

If device implementations add or modify the authentication methods to unlock the lock screen, then for such an authentication method to be treated as a secure way to lock the screen, they:

If device implementations add or modify the authentication methods to unlock the lock screen if based on a known secret then for such an authentication method to be treated as a secure way to lock the screen, they:

  • [C-3-1] 允許的最短輸入長度的熵必須大於 10 位元。
  • [C-3-2] 所有可能輸入的最大熵必須大於 18 位元。
  • [C-3-3] MUST not replace any of the existing authentication methods (PIN,pattern, password) implemented and provided in AOSP.
  • [C-3-4] MUST be disabled when the Device Policy Controller (DPC) application has set the password quality policy via the DevicePolicyManager.setPasswordQuality() method with a more restrictive quality constant than PASSWORD_QUALITY_SOMETHING .

If device implementations add or modify the authentication methods to unlock the lock screen if based on a physical token or the location, then for such an authentication method to be treated as a secure way to lock the screen, they:

  • [C-4-1] MUST have a fall-back mechanism to use one of the primary authentication methods which is based on a known secret and meets the requirements to be treated as a secure lock screen.
  • [C-4-2] MUST be disabled and only allow the primary authentication to unlock the screen when the Device Policy Controller (DPC) application has set the policy with either the DevicePolicyManager.setKeyguardDisabledFeatures(KEYGUARD_DISABLE_TRUST_AGENTS) method or the DevicePolicyManager.setPasswordQuality() method with a more restrictive quality constant than PASSWORD_QUALITY_UNSPECIFIED .
  • [C-4-3] The user MUST be challenged for the primary authentication (egPIN, pattern, password) at least once every 72 hours or less.

If device implementations add or modify the authentication methods to unlock the lock screen based on biometrics, then for such an authentication method to be treated as a secure way to lock the screen, they:

  • [C-5-1] MUST have a fall-back mechanism to use one of the primary authentication methods which is based on a known secret and meets the requirements to be treated as a secure lock screen.
  • [C-5-2] MUST be disabled and only allow the primary authentication to unlock the screen when the Device Policy Controller (DPC) application has set the keguard feature policy by calling the method DevicePolicyManager.setKeyguardDisabledFeatures(KEYGUARD_DISABLE_FINGERPRINT) .
  • [C-5-3] MUST have a false acceptance rate that is equal or stronger than what is required for a fingerprint sensor as described in section 7.3.10, or otherwise MUST be disabled and only allow the primary authentication to unlock the screen when the Device Policy Controller (DPC) application has set the password quality policy via the DevicePolicyManager.setPasswordQuality() method with a more restrictive quality constant than PASSWORD_QUALITY_BIOMETRIC_WEAK .
  • [SR] Are STRONGLY RECOMMENDED to have spoof and imposter acceptance rates that are equal to or stronger than what is required for a fingerprint sensor as described in section 7.3.10.

If the spoof and imposter acceptance rates are not equal to or stronger than what is required for a fingerprint sensor as described in section 7.3.10 and the Device Policy Controller (DPC) application has set the password quality policy via the DevicePolicyManager.setPasswordQuality() method with a more restrictive quality constant than PASSWORD_QUALITY_BIOMETRIC_WEAK , then:

  • [C-6-1] MUST disable these biometric methods and allow only the primary authentication to unlock the screen.
  • [C-6-2] MUST challenge the user for the primary authentication (egPIN, pattern, password) at least once every 72 hours or less.

If device implementations add or modify the authentication methods to unlock the lock screen and if such an authentication method will be used to unlock the keyguard, but will not be treated as a secure lock screen, then they:

9.12.資料刪除

All device implementations:

  • [C-0-1] MUST provide users a mechanism to perform a "Factory Data Reset".
  • [C-0-2] MUST delete all user-generated data. That is, all data except for the following:
    • The system image
    • Any operating system files required by the system image
  • [C-0-3] MUST delete the data in such a way that will satisfy relevant industry standards such as NIST SP800-88.
  • [C-0-4] MUST trigger the above "Factory Data Reset" process when the DevicePolicyManager.wipeData() API is called by the primary user's Device Policy Controller app.
  • MAY provide a fast data wipe option that conducts only a logical data erase.

9.13。安全啟動模式

Android provides Safe Boot Mode, which allows users to boot up into a mode where only preinstalled system apps are allowed to run and all third-party apps are disabled. This mode, known as "Safe Boot Mode", provides the user the capability to uninstall potentially harmful third-party apps.

Device implementations are:

  • [SR] STRONGLY RECOMMENDED to implement Safe Boot Mode.

If device implementations implement Safe Boot Mode, they:

  • [C-1-1] MUST provide the user an option to enter Safe Boot Mode in such a way that is uninterruptible from third-party apps installed on the device, except when the third-party app is a Device Policy Controller and has set the UserManager.DISALLOW_SAFE_BOOT flag as true.

  • [C-1-2] MUST provide the user the capability to uninstall any third-party apps within Safe Mode.

  • SHOULD provide the user an option to enter Safe Boot Mode from the boot menu using a workflow that is different from that of a normal boot.

9.14。汽車車輛系統隔離

Android Automotive devices are expected to exchange data with critical vehicle subsystems by using the vehicle HAL to send and receive messages over vehicle networks such as CAN bus.

The data exchange can be secured by implementing security features below the Android framework layers to prevent malicious or unintentional interaction with these subsystems.

10.軟體相容性測試

設備實作必須通過本節中所述的所有測試。

但是,請注意,沒有軟體測試軟體包是完全全面的。 For this reason, device implementers are STRONGLY RECOMMENDED to make the minimum number of changes as possible to the reference and preferred implementation of Android available from the Android Open Source Project.這將最大程度地降低引入錯誤的風險,從而創建不相容,需要返工和潛在的設備更新。

10.1.相容性測試套件

Device implementations MUST pass the Android Compatibility Test Suite (CTS) available from the Android Open Source Project, using the final shipping software on the device.此外,設備實施者應盡可能使用Android開源樹中的參考實現,並且必須確保在CTS含糊不清以及參考原始碼部分的任何重新實現的情況下相容。

CTS設計為在實際設備上運作。像任何軟體一樣,CTS本身可能包含錯誤。 The CTS will be versioned independently of this Compatibility Definition, and multiple revisions of the CTS may be released for Android 8.1.設備實作必須傳遞設備軟體完成時可用的最新CTS版本。

10.2. CTS驗證器

設備實作必須正確執行CTS驗證者中的所有適用案例。 CTS驗證儀包含在相容性測試套件中,旨在由人類操作員運行,以測試無法通過自動化系統測試的功能,例如相機和感測器的正確功能。

CTS驗證儀對許多硬體進行了測試,包括一些可選的硬體。 Device implementations MUST pass all tests for hardware that they possess;例如,如果裝置具有加速度計,則必須在CTS驗證器中正確執行加速度計測試案例。可以跳過或省略此相容性定義文件所指出的功能的測試案例。

如上所述,每個設備和每個建置都必須正確運行CTS驗證器。但是,由於許多建置非常相似,因此不會期望裝置實作者明確地在僅以微不足道的方式上建置的CTS驗證器。 Specifically, device implementations that differ from an implementation that has passed the CTS Verifier only by the set of included locales, branding, etc. MAY omit the CTS Verifier test.

11. 可更新的軟體

設備實現必須包括替換整個系統軟體的機制。 The mechanism need not perform “live” upgrades—that is, a device restart MAY be required.

只要可以替換設備上預先安裝的整個軟體,就可以使用任何方法。例如,以下任何方法都可以滿足此要求:

  • “Over-the-air (OTA)” downloads with offline update via reboot.
  • “Tethered” updates over USB from a host PC.
  • “Offline” updates via a reboot and update from a file on removable storage.

However, if the device implementation includes support for an unmetered data connection such as 802.11 or Bluetooth PAN (Personal Area Network) profile, it MUST support OTA downloads with offline update via reboot.

所使用的更新機制必須支援更新,而無需擦除使用者資料。也就是說,更新機制必須保留應用程式私人資料和應用程式共享資料。請注意,上游Android軟體包括滿足此要求的更新機制。

For device implementations that are launching with Android 6.0 and later, the update mechanism SHOULD support verifying that the system image is binary identical to expected result following an OTA. The block-based OTA implementation in the upstream Android Open Source Project, added since Android 5.1, satisfies this requirement.

Also, device implementations SHOULD support A/B system updates . The AOSP implements this feature using the boot control HAL.

如果在發布後在設備實作中發現錯誤,但在其合理的產品壽命內與Android相容性團隊協商確定以影響第三方應用程式的相容性,則裝置實作者必須透過軟體修正錯誤可根據剛才描述的機制應用的更新。

Android includes features that allow the Device Owner app (if present) to control the installation of system updates. To facilitate this, the system update subsystem for devices that report android.software.device_admin MUST implement the behavior described in the SystemUpdatePolicy class.

12. 文件變更日誌

For a summary of changes to the Compatibility Definition in this release:

For a summary of changes to individuals sections:

  1. 介紹
  2. 設備類型
  3. 軟體
  4. 應用程式封裝
  5. 多媒體
  6. Developer Tools and Options
  7. 硬體相容性
  8. 性能和功率
  9. 安全模型
  10. Software Compatibility Testing
  11. Updatable Software
  12. Document Changelog
  13. 聯絡我們

12.1。 Changelog Viewing Tips

Changes are marked as follows:

  • CDD
    Substantive changes to the compatibility requirements.

  • 文件
    Cosmetic or build related changes.

For best viewing, append the pretty=full and no-merges URL parameters to your changelog URLs.

13. 聯絡我們

You can join the android-compatibility forum and ask for clarifications or bring up any issues that you think the document does not cover.