2025 年 3 月 27 日より、AOSP のビルドとコントリビューションには aosp-main
ではなく android-latest-release
を使用することをおすすめします。詳細については、AOSP の変更をご覧ください。
設定のサブタイトル
コレクションでコンテンツを整理
必要に応じて、コンテンツの保存と分類を行います。
ほとんどの場合、設定の概要は比較的簡単に追加できます。必要なのは、適切な文字列リソースを使用して、それぞれの設定に android:summary
属性を追加することだけです。ただし、サブタイトルを動的に更新する必要がある場合は、カスタムの設定コントローラが必要になることがあります。
静的なサブタイトル
設定に静的なサブタイトルを追加するには、次のようにします。
- 設定に
android:summary
属性を追加します。たとえば、L0 ディスプレイの設定に概要を追加するには、設定の属性に次のような行を追加します。
android:summary="@string/display_settings_summary"
この場合、設定コードサンプルの全体は次のようになります。
<Preference
android:fragment="com.android.car.settings.display.DisplaySettingsFragment"
android:icon="@drawable/ic_settings_display"
android:key="@string/pk_display_settings_entry"
android:title="@string/display_settings"
android:summary="@string/display_settings_summary"
settings:controller="com.android.car.settings.common.DefaultRestrictionsPreferenceController"/>
動的なサブタイトル
android:summary
属性で指定されたサブタイトルは静的であるため、特定の条件に基づいて更新することはできません。動的なサブタイトルの場合、設定に応じて設定コントローラを変更する必要があります。次の例では、L0 の位置情報の設定を変更して、位置情報のオン / オフを指定するサブタイトルを追加し、オンの場合、位置情報へのアクセスが許可されているアプリの数が表示されるようにしています。
- 新しい文字列を定義します。
<!-- Summary for Location settings when location is off [CHAR LIMIT=NONE] -->
<string name="location_settings_summary_location_off">Off</string>
<!-- Summary for Location settings when location is on, explaining how many apps have location permission [CHAR LIMIT=NONE]-->
<plurals name="location_settings_summary_location_on">
<item quantity="one">On - <xliff:g id="count">%1$d</xliff:g> app has access to location</item>
<item quantity="other">On - <xliff:g id="count">%1$d</xliff:g> apps have access to location</item>
</plurals>
<!-- Location settings, loading the number of apps which have location permission [CHAR LIMIT=30] -->
<string name="location_settings_loading_app_permission_stats">Loading\u2026</string>
LocationEntryPreferenceController
を作成します。この新しい PreferenceController により、位置情報設定の概要テキストを動的に設定および変更します。
public class LocationEntryPreferenceController extends PreferenceController<Preference> {
private static final Logger LOG = new Logger(LocationEntryPreferenceController.class);
private static final IntentFilter INTENT_FILTER_LOCATION_MODE_CHANGED =
new IntentFilter(LocationManager.MODE_CHANGED_ACTION);
private final Context mContext;
private final LocationManager mLocationManager;
/** Total number of apps that have location permissions. */
private int mNumTotal = -1;
private int mNumTotalLoading = 0;
private AtomicInteger mLoadingInProgress = new AtomicInteger(0);
private final BroadcastReceiver mReceiver = new BroadcastReceiver() {
@Override
public void onReceive(Context context, Intent intent) {
refreshUi();
}
};
public LocationEntryPreferenceController(Context context, String preferenceKey,
FragmentController fragmentController, CarUxRestrictions uxRestrictions) {
super(context, preferenceKey, fragmentController, uxRestrictions);
mContext = context;
mLocationManager = (LocationManager) getContext().getSystemService(
Service.LOCATION_SERVICE);
}
@Override
protected Class<Preference> getPreferenceType() {
return Preference.class;
}
@Override
protected void onStartInternal() {
getContext().registerReceiver(mReceiver, INTENT_FILTER_LOCATION_MODE_CHANGED);
}
@Override
protected void onStopInternal() {
getContext().unregisterReceiver(mReceiver);
}
@Override
protected void updateState(Preference preference) {
super.updateState(preference);
updateSummary(preference);
if (!mLocationManager.isLocationEnabled() || mLoadingInProgress.get() != 0) {
return;
}
mNumTotalLoading = 0;
// Retrieve a list of users inside the current user profile group.
List<UserHandle> users = mContext.getSystemService(
UserManager.class).getUserProfiles();
mLoadingInProgress.set(users.size());
for (UserHandle user : users) {
Context userContext = createPackageContextAsUser(mContext, user.getIdentifier());
if (userContext == null) {
if (mLoadingInProgress.decrementAndGet() == 0) {
setLocationAppCount(preference, mNumTotalLoading);
}
continue;
}
PermissionControllerManager permController =
userContext.getSystemService(PermissionControllerManager.class);
permController.countPermissionApps(
Arrays.asList(ACCESS_FINE_LOCATION, ACCESS_COARSE_LOCATION),
PermissionControllerManager.COUNT_ONLY_WHEN_GRANTED,
(numApps) -> {
mNumTotalLoading += numApps;
if (mLoadingInProgress.decrementAndGet() == 0) {
setLocationAppCount(preference, mNumTotalLoading);
}
}, null);
}
}
@VisibleForTesting
void setLocationAppCount(Preference preference, int numApps) {
mNumTotal = numApps;
updateSummary(preference);
}
private void updateSummary(Preference preference) {
String summary = "";
if (mLocationManager.isLocationEnabled()) {
if (mNumTotal == -1) {
summary = mContext.getString(R.string.location_settings_loading_app_permission_stats);
} else {
summary = mContext.getResources().getQuantityString(
R.plurals.location_settings_summary_location_on,
mNumTotal, mNumTotal);
}
} else {
summary = mContext.getString(R.string.location_settings_summary_location_off);
}
preference.setSummary(summary);
}
private Context createPackageContextAsUser(Context context, int userId) {
try {
return context.createPackageContextAsUser(
context.getPackageName(), 0 /* flags */, UserHandle.of(userId));
} catch (PackageManager.NameNotFoundException e) {
LOG.e("Failed to create user context", e);
}
return null;
}
}
このサンプル コントローラは次のように機能します。
- 位置情報が無効になっている場合、概要テキストは
location_settings_summary_location_off
文字列に設定されます。
- 位置情報が有効になっている場合、位置情報の利用許可が付与されているアプリの数が追加されます。読み込み中は、
location_settings_loading_app_permission_stats
文字列が表示されます。データの読み込み時に、コントローラは概要を location_settings_summary_location_on
文字列に設定するとともに、アクセス権限を持つアプリの数を指定します。
- 設定コントローラが起動されると、コントローラはレシーバを登録し、位置情報の状態が変化したときに設定の状態を更新します。
- フラグメントの XML ファイルを変更して、新しいコントローラを関連する設定にアタッチします。
<Preference
android:fragment="com.android.car.settings.location.LocationSettingsFragment"
android:icon="@drawable/ic_settings_location"
android:key="@string/pk_location_settings_entry"
android:title="@string/location_settings_title"
settings:controller="com.android.car.settings.location.LocationEntryPreferenceController"/>
このページのコンテンツやコードサンプルは、コンテンツ ライセンスに記載のライセンスに従います。Java および OpenJDK は Oracle および関連会社の商標または登録商標です。
最終更新日 2025-07-27 UTC。
[[["わかりやすい","easyToUnderstand","thumb-up"],["問題の解決に役立った","solvedMyProblem","thumb-up"],["その他","otherUp","thumb-up"]],[["必要な情報がない","missingTheInformationINeed","thumb-down"],["複雑すぎる / 手順が多すぎる","tooComplicatedTooManySteps","thumb-down"],["最新ではない","outOfDate","thumb-down"],["翻訳に関する問題","translationIssue","thumb-down"],["サンプル / コードに問題がある","samplesCodeIssue","thumb-down"],["その他","otherDown","thumb-down"]],["最終更新日 2025-07-27 UTC。"],[],[],null,["# Preference subtitles\n\nFor the most part, adding preference summaries is relatively straightforward as it\ninvolves just adding the `android:summary` attribute to the respective preference\nwith the appropriate string resource. However, if the subtitles should update dynamically\nthen a custom preference controller may be necessary.\n\nStatic subtitles\n----------------\n\nTo add a static subtitle to a preference:\n\n1. Add the `android:summary` attribute to the preference. For example, to add a summary to the L0 display settings preference, add something like the following to the preference attributes: \n\n android:summary=\"@string/display_settings_summary\"\n\n For example, consider this full preference code sample: \n\n ```\n \u003cPreference\n android:fragment=\"com.android.car.settings.display.DisplaySettingsFragment\"\n android:icon=\"@drawable/ic_settings_display\"\n android:key=\"@string/pk_display_settings_entry\"\n android:title=\"@string/display_settings\"\n android:summary=\"@string/display_settings_summary\"\n settings:controller=\"com.android.car.settings.common.DefaultRestrictionsPreferenceController\"/\u003e\n ```\n\nDynamic subtitles\n-----------------\n\nSubtitles specified with the `android:summary` attribute are static so cannot\nupdate based on certain conditions. For dynamic subtitles, you need to modify the preference\ncontroller for the preference. The following example modifies the L0 location preference to\nhave a subtitle that specifies if location is on or off and, if on, state how many apps\ncurrently have location access.\n\n1. Define the new strings: \n\n ```\n \u003c!-- Summary for Location settings when location is off [CHAR LIMIT=NONE] --\u003e\n \u003cstring name=\"location_settings_summary_location_off\"\u003eOff\u003c/string\u003e\n \u003c!-- Summary for Location settings when location is on, explaining how many apps have location permission [CHAR LIMIT=NONE]--\u003e\n \u003cplurals name=\"location_settings_summary_location_on\"\u003e\n \u003citem quantity=\"one\"\u003eOn - \u003cxliff:g id=\"count\"\u003e%1$d\u003c/xliff:g\u003e app has access to location\u003c/item\u003e\n \u003citem quantity=\"other\"\u003eOn - \u003cxliff:g id=\"count\"\u003e%1$d\u003c/xliff:g\u003e apps have access to location\u003c/item\u003e\n \u003c/plurals\u003e\n \u003c!-- Location settings, loading the number of apps which have location permission [CHAR LIMIT=30] --\u003e\n \u003cstring name=\"location_settings_loading_app_permission_stats\"\u003eLoading\\u2026\u003c/string\u003e\n ```\n2. Create a new PreferenceController, `LocationEntryPreferenceController`, to dynamically set and change the location preference summary text: \n\n ```\n public class LocationEntryPreferenceController extends PreferenceController\u003cPreference\u003e {\n\n private static final Logger LOG = new Logger(LocationEntryPreferenceController.class);\n private static final IntentFilter INTENT_FILTER_LOCATION_MODE_CHANGED =\n new IntentFilter(LocationManager.MODE_CHANGED_ACTION);\n\n private final Context mContext;\n private final LocationManager mLocationManager;\n /** Total number of apps that have location permissions. */\n private int mNumTotal = -1;\n private int mNumTotalLoading = 0;\n private AtomicInteger mLoadingInProgress = new AtomicInteger(0);\n\n private final BroadcastReceiver mReceiver = new BroadcastReceiver() {\n @Override\n public void onReceive(Context context, Intent intent) {\n refreshUi();\n }\n };\n\n public LocationEntryPreferenceController(Context context, String preferenceKey,\n FragmentController fragmentController, CarUxRestrictions uxRestrictions) {\n super(context, preferenceKey, fragmentController, uxRestrictions);\n mContext = context;\n mLocationManager = (LocationManager) getContext().getSystemService(\n Service.LOCATION_SERVICE);\n }\n\n @Override\n protected Class\u003cPreference\u003e getPreferenceType() {\n return Preference.class;\n }\n\n @Override\n protected void onStartInternal() {\n getContext().registerReceiver(mReceiver, INTENT_FILTER_LOCATION_MODE_CHANGED);\n }\n\n @Override\n protected void onStopInternal() {\n getContext().unregisterReceiver(mReceiver);\n }\n\n @Override\n protected void updateState(Preference preference) {\n super.updateState(preference);\n updateSummary(preference);\n if (!mLocationManager.isLocationEnabled() || mLoadingInProgress.get() != 0) {\n return;\n }\n mNumTotalLoading = 0;\n // Retrieve a list of users inside the current user profile group.\n List\u003cUserHandle\u003e users = mContext.getSystemService(\n UserManager.class).getUserProfiles();\n mLoadingInProgress.set(users.size());\n for (UserHandle user : users) {\n Context userContext = createPackageContextAsUser(mContext, user.getIdentifier());\n if (userContext == null) {\n if (mLoadingInProgress.decrementAndGet() == 0) {\n setLocationAppCount(preference, mNumTotalLoading);\n }\n continue;\n }\n PermissionControllerManager permController =\n userContext.getSystemService(PermissionControllerManager.class);\n permController.countPermissionApps(\n Arrays.asList(ACCESS_FINE_LOCATION, ACCESS_COARSE_LOCATION),\n PermissionControllerManager.COUNT_ONLY_WHEN_GRANTED,\n (numApps) -\u003e {\n mNumTotalLoading += numApps;\n if (mLoadingInProgress.decrementAndGet() == 0) {\n setLocationAppCount(preference, mNumTotalLoading);\n }\n }, null);\n }\n }\n\n @VisibleForTesting\n void setLocationAppCount(Preference preference, int numApps) {\n mNumTotal = numApps;\n updateSummary(preference);\n }\n\n private void updateSummary(Preference preference) {\n String summary = \"\";\n if (mLocationManager.isLocationEnabled()) {\n if (mNumTotal == -1) {\n summary = mContext.getString(R.string.location_settings_loading_app_permission_stats);\n } else {\n summary = mContext.getResources().getQuantityString(\n R.plurals.location_settings_summary_location_on,\n mNumTotal, mNumTotal);\n }\n } else {\n summary = mContext.getString(R.string.location_settings_summary_location_off);\n }\n preference.setSummary(summary);\n }\n\n private Context createPackageContextAsUser(Context context, int userId) {\n try {\n return context.createPackageContextAsUser(\n context.getPackageName(), 0 /* flags */, UserHandle.of(userId));\n } catch (PackageManager.NameNotFoundException e) {\n LOG.e(\"Failed to create user context\", e);\n }\n return null;\n }\n }\n ```\n\n For this sample controller:\n - If location is disabled, summary text is set to the `location_settings_summary_location_off` string.\n - If location is enabled, the number of apps that have location permission is added. While this is loading, the `location_settings_loading_app_permission_stats` string is shown. When the data is loaded, the controller sets the summary to the `location_settings_summary_location_on` string with the number of apps with access specified.\n - When the preference controller is started, the controller registers a receiver and refreshes the preference state when the location state changes.\n3. Modify the fragment XML file to attach the new controller to the relevant preference: \n\n ```\n \u003cPreference\n android:fragment=\"com.android.car.settings.location.LocationSettingsFragment\"\n android:icon=\"@drawable/ic_settings_location\"\n android:key=\"@string/pk_location_settings_entry\"\n android:title=\"@string/location_settings_title\"\n settings:controller=\"com.android.car.settings.location.LocationEntryPreferenceController\"/\u003e\n ```"]]