行为变更：以 Android 15 或更高版本为目标平台的应用

与之前的版本一样，Android 15 包含一些可能会影响您的应用的行为变更。以下行为变更仅影响以 Android 15 或更高版本为目标平台的应用。如果您的应用以 Android 15 或更高版本为目标平台，您应该修改自己的应用以适当地支持这些行为（如果适用）。

请务必查看对 Android 15 上运行的所有应用都有影响的行为变更列表（无论应用的 targetSdkVersion 如何）。

核心功能

Android 15 修改或扩展了 Android 系统的各种核心功能。

前台服务变更

We are making the following changes to foreground services with Android 15.

• Data sync foreground service timeout behavior
• New media processing foreground service type
• Restrictions on BOOT_COMPLETED broadcast receivers launching foreground services
• Restrictions on starting foreground services while an app holds the SYSTEM_ALERT_WINDOW permission

Data sync foreground service timeout behavior

Android 15 introduces a new timeout behavior to dataSync for apps targeting Android 15 (API level 35) or higher. This behavior also applies to the new mediaProcessing foreground service type.

The system permits an app's dataSync services to run for a total of 6 hours in a 24-hour period, after which the system calls the running service's Service.onTimeout(int, int) method (introduced in Android 15). At this time, the service has a few seconds to call Service.stopSelf(). When Service.onTimeout() is called, the service is no longer considered a foreground service. If the service does not call Service.stopSelf(), the system throws an internal exception. The exception is logged in Logcat with the following message:

Fatal Exception: android.app.RemoteServiceException: "A foreground service of
type dataSync did not stop within its timeout: [component name]"

To avoid problems with this behavior change, you can do one or more of the following:

1. Have your service implement the new Service.onTimeout(int, int) method. When your app receives the callback, make sure to call stopSelf() within a few seconds. (If you don't stop the app right away, the system generates a failure.)
2. Make sure your app's dataSync services don't run for more than a total of 6 hours in any 24-hour period (unless the user interacts with the app, resetting the timer).
3. Only start dataSync foreground services as a result of direct user interaction; since your app is in the foreground when the service starts, your service has the full six hours after the app goes to the background.
4. Instead of using a dataSync foreground service, use an alternative API.

If your app's dataSync foreground services have run for 6 hours in the last 24, you cannot start another dataSync foreground service unless the user has brought your app to the foreground (which resets the timer). If you try to start another dataSync foreground service, the system throws ForegroundServiceStartNotAllowedException with an error message like "Time limit already exhausted for foreground service type dataSync".

Testing

To test your app's behavior, you can enable data sync timeouts even if your app is not targeting Android 15 (as long as the app is running on an Android 15 device). To enable timeouts, run the following adb command:

adb shell am compat enable FGS_INTRODUCE_TIME_LIMITS your-package-name

You can also adjust the timeout period, to make it easier to test how your app behaves when the limit is reached. To set a new timeout period, run the following adb command:

adb shell device_config put activity_manager data_sync_fgs_timeout_duration duration-in-milliseconds

New media processing foreground service type

Android 15 引入了一种新的前台服务类型 mediaProcessing。此服务类型适用于转码媒体文件等操作。例如，媒体应用可能会下载音频文件，并需要先将其转换为其他格式，然后才能播放。您可以使用 mediaProcessing 前台服务，确保即使应用在后台运行时转换也会继续。

系统允许应用的 mediaProcessing 服务在 24 小时内总共运行 6 小时，之后系统会调用正在运行的服务的 Service.onTimeout(int, int) 方法（在 Android 15 中引入）。此时，服务有几秒钟的时间来调用 Service.stopSelf()。如果服务未调用 Service.stopSelf()，系统会抛出内部异常。系统会在 Logcat 中记录此异常，并显示以下消息：

Fatal Exception: android.app.RemoteServiceException: "A foreground service of
type mediaProcessing did not stop within its timeout: [component name]"

为避免出现此异常，您可以执行以下任一操作：

1. 让您的服务实现新的 Service.onTimeout(int, int) 方法。当您的应用收到回调时，请务必在几秒钟内调用 stopSelf()。（如果您未立即停止应用，系统会生成失败情况。）
2. 确保应用的 mediaProcessing 服务在任何 24 小时内总运行时间不超过 6 小时（除非用户与应用互动，重置计时器）。
3. 仅在有直接用户互动时启动 mediaProcessing 前台服务；由于服务启动时应用位于前台，因此您的服务在应用进入后台后有完整的 6 小时时间。
4. 请改用 替代 API（例如 WorkManager），而不是使用 mediaProcessing 前台服务。

如果您的应用的 mediaProcessing 前台服务在过去 24 小时内运行了 6 小时，则您无法启动其他 mediaProcessing 前台服务，除非用户将您的应用切换到前台（这会重置计时器）。如果您尝试启动另一个 mediaProcessing 前台服务，系统会抛出 ForegroundServiceStartNotAllowedException，并显示类似于“前台服务类型 mediaProcessing 的时间限制已用尽”的错误消息。

如需详细了解 mediaProcessing 服务类型，请参阅 Android 15 前台服务类型变更：媒体处理。

测试

如需测试应用的行为，您可以启用媒体处理超时，即使您的应用并非以 Android 15 为目标平台也是如此（前提是应用在 Android 15 设备上运行）。如需启用超时，请运行以下 adb 命令：

adb shell am compat enable FGS_INTRODUCE_TIME_LIMITS your-package-name

您还可以调整超时期限，以便更轻松地测试应用在达到上限时的行为方式。如需设置新的超时期限，请运行以下 adb 命令：

adb shell device_config put activity_manager media_processing_fgs_timeout_duration duration-in-milliseconds

Restrictions on BOOT_COMPLETED broadcast receivers launching foreground services

There are new restrictions on BOOT_COMPLETED broadcast receivers launching foreground services. BOOT_COMPLETED receivers are not allowed to launch the following types of foreground services:

• dataSync
• camera
• mediaPlayback
• phoneCall
• mediaProjection
• microphone (this restriction has been in place for microphone since Android 14)

If a BOOT_COMPLETED receiver tries to launch any of those types of foreground services, the system throws ForegroundServiceStartNotAllowedException.

Testing

To test your app's behavior, you can enable these new restrictions even if your app is not targeting Android 15 (as long as the app is running on an Android 15 device). Run the following adb command:

adb shell am compat enable FGS_BOOT_COMPLETED_RESTRICTIONS your-package-name

To send a BOOT_COMPLETED broadcast without restarting the device, run the following adb command:

adb shell am broadcast -a android.intent.action.BOOT_COMPLETED your-package-name

Restrictions on starting foreground services while an app holds the SYSTEM_ALERT_WINDOW permission

Previously, if an app held the SYSTEM_ALERT_WINDOW permission, it could launch a foreground service even if the app was currently in the background (as discussed in exemptions from background start restrictions).

If an app targets Android 15, this exemption is now narrower. The app now needs to have the SYSTEM_ALERT_WINDOW permission and also have a visible overlay window. That is, the app needs to first launch a TYPE_APPLICATION_OVERLAY window and the window needs to be visible before you start a foreground service.

If your app attempts to start a foreground service from the background without meeting these new requirements (and it does not have some other exemption), the system throws ForegroundServiceStartNotAllowedException.

If your app declares the SYSTEM_ALERT_WINDOW permission and launches foreground services from the background, it may be affected by this change. If your app gets a ForegroundServiceStartNotAllowedException, check your app's order of operations and make sure your app already has an active overlay window before it attempts to start a foreground service from the background. You can check if your overlay window is currently visible by calling View.getWindowVisibility(), or you can override View.onWindowVisibilityChanged() to get notified whenever the visibility changes.

Testing

To test your app's behavior, you can enable these new restrictions even if your app is not targeting Android 15 (as long as the app is running on an Android 15 device). To enable these new restrictions on starting foreground services from the background, run the following adb command:

adb shell am compat enable FGS_SAW_RESTRICTIONS your-package-name

更改了应用可以修改“勿扰”模式全局状态的时间

Apps that target Android 15 (API level 35) and higher can no longer change the global state or policy of Do Not Disturb (DND) on a device (either by modifying user settings, or turning off DND mode). Instead, apps must contribute an AutomaticZenRule, which the system combines into a global policy with the existing most-restrictive-policy-wins scheme. Calls to existing APIs that previously affected global state (setInterruptionFilter, setNotificationPolicy) result in the creation or update of an implicit AutomaticZenRule, which is toggled on and off depending on the call-cycle of those API calls.

Note that this change only affects observable behavior if the app is calling setInterruptionFilter(INTERRUPTION_FILTER_ALL) and expects that call to deactivate an AutomaticZenRule that was previously activated by their owners.

OpenJDK API 变更

Android 15 continues the work of refreshing Android's core libraries to align with the features in the latest OpenJDK LTS releases.

Some of these changes can affect app compatibility for apps targeting Android 15 (API level 35):

• Changes to string formatting APIs: Validation of argument index, flags, width, and precision are now more strict when using the following String.format() and Formatter.format() APIs:

  • String.format(String, Object[])
  • String.format(Locale, String, Object[])
  • Formatter.format(String, Object[])
  • Formatter.format(Locale, String, Object[])

  For example, the following exception is thrown when an argument index of 0 is used (%0 in the format string):

  IllegalFormatArgumentIndexException: Illegal format argument index = 0
  

  In this case, the issue can be fixed by using an argument index of 1 (%1 in the format string).

• Changes to component type of Arrays.asList(...).toArray(): When using Arrays.asList(...).toArray(), the component type of the resulting array is now an Object—not the type of the underlying array's elements. So the following code throws a ClassCastException:

  String[] elements = (String[]) Arrays.asList("one", "two").toArray();
  

  For this case, to preserve String as the component type in the resulting array, you could use Collection.toArray(Object[]) instead:

  String[] elements = Arrays.asList("two", "one").toArray(new String[0]);
  

• Changes to language code handling: When using the Locale API, language codes for Hebrew, Yiddish, and Indonesian are no longer converted to their obsolete forms (Hebrew: iw, Yiddish: ji, and Indonesian: in). When specifying the language code for one of these locales, use the codes from ISO 639-1 instead (Hebrew: he, Yiddish: yi, and Indonesian: id).

• Changes to random int sequences: Following the changes made in https://bugs.openjdk.org/browse/JDK-8301574, the following Random.ints() methods now return a different sequence of numbers than the Random.nextInt() methods do:

  • Random.ints(long)
  • Random.ints(long, int, int)
  • Random.ints(int, int)
  • Random.ints()

  Generally, this change shouldn't result in app-breaking behavior, but your code shouldn't expect the sequence generated from Random.ints() methods to match Random.nextInt().

The new SequencedCollection API can affect your app's compatibility after you update compileSdk in your app's build configuration to use Android 15 (API level 35):

• Collision with MutableList.removeFirst() and MutableList.removeLast() extension functions in kotlin-stdlib

  The List type in Java is mapped to the MutableList type in Kotlin. Because the List.removeFirst() and List.removeLast() APIs have been introduced in Android 15 (API level 35), the Kotlin compiler resolves function calls, for example list.removeFirst(), statically to the new List APIs instead of to the extension functions in kotlin-stdlib.

  If an app is re-compiled with compileSdk set to 35 and minSdk set to 34 or lower, and then the app is run on Android 14 and lower, a runtime error is thrown:

  java.lang.NoSuchMethodError: No virtual method
  removeFirst()Ljava/lang/Object; in class Ljava/util/ArrayList;
  

  The existing NewApi lint option in Android Gradle Plugin can catch these new API usages.

  ./gradlew lint
  
  MainActivity.kt:41: Error: Call requires API level 35 (current min is 34): java.util.List#removeFirst [NewApi]
        list.removeFirst()
  

  To fix the runtime exception and lint errors, the removeFirst() and removeLast() function calls can be replaced with removeAt(0) and removeAt(list.lastIndex) respectively in Kotlin. If you're using Android Studio Ladybug | 2024.1.3 or higher, it also provides a quick fix option for these errors.

  Consider removing @SuppressLint("NewApi") and lintOptions { disable 'NewApi' } if the lint option has been disabled.

• Collision with other methods in Java

  New methods have been added into the existing types, for example, List and Deque. These new methods might not be compatible with the methods with the same name and argument types in other interfaces and classes. In the case of a method signature collision with incompatibility, the javac compiler outputs a build-time error. For example:

  Example error 1:

  javac MyList.java
  
  MyList.java:135: error: removeLast() in MyList cannot implement removeLast() in List
    public void removeLast() {
                ^
    return type void is not compatible with Object
    where E is a type-variable:
      E extends Object declared in interface List
  

  Example error 2:

  javac MyList.java
  
  MyList.java:7: error: types Deque<Object> and List<Object> are incompatible;
  public class MyList implements  List<Object>, Deque<Object> {
    both define reversed(), but with unrelated return types
  1 error
  

  Example error 3:

  javac MyList.java
  
  MyList.java:43: error: types List<E#1> and MyInterface<E#2> are incompatible;
  public static class MyList implements List<Object>, MyInterface<Object> {
    class MyList inherits unrelated defaults for getFirst() from types List and MyInterface
    where E#1,E#2 are type-variables:
      E#1 extends Object declared in interface List
      E#2 extends Object declared in interface MyInterface
  1 error
  

  To fix these build errors, the class implementing these interfaces should override the method with a compatible return type. For example:

  @Override
  public Object getFirst() {
      return List.super.getFirst();
  }
  

安全

Android 15 包含多项旨在提升系统安全性的变更，以帮助保护应用和用户免受恶意应用的侵害。

受限的 TLS 版本

Android 15 限制了对 TLS 版本 1.0 和 1.1 的使用。这些版本之前已在 Android 中被弃用，但现在不允许面向 Android 15 的应用使用。

限制后台 activity 启动

Android 15 可保护用户免受恶意应用的侵害，并让用户更好地控制 来防止恶意后台应用 将其他应用置于前台、提升其权限以及滥用 用户互动自以下时间以来，后台活动启动一直受到限制 Android 10（API 级别 29）。

其他变更

除了 UID 匹配限制之外，还包括以下其他更改：

• 默认情况下，将 PendingIntent 创建者更改为屏蔽后台活动启动。这有助于防止应用意外创建可能会被恶意操作者滥用的 PendingIntent。
• 除非 PendingIntent 发件人允许，否则请勿将应用调至前台。此变更旨在防止恶意应用滥用 在后台启动 activity 的功能。默认情况下，应用 允许将任务堆栈转到前台，除非创建者允许 后台活动启动权限或发送者有后台活动 启动权限
• 控制任务堆栈顶部 activity 如何完成其任务。如果顶部 activity 完成任务，Android 将返回上次处于活动状态的任务。此外，如果非顶层 activity 完成其任务，Android 将 返回主屏幕；它不会挡住这个非顶层的 活动。
• 防止将其他应用中的任意 activity 启动到您自己的 activity 任务。这项变更可防止恶意应用通过创建看似来自其他应用的 activity 来钓鱼式攻击用户。
• 阻止系统考虑非可见窗口来启动后台 activity。这有助于防止恶意应用滥用后台 activity 启动来向用户显示不需要或恶意的内容。

更安全的 intent

Android 15 introduces new optional security measures to make intents safer and more robust. These changes are aimed at preventing potential vulnerabilities and misuse of intents that can be exploited by malicious apps. There are two main improvements to the security of intents in Android 15:

• Match target intent-filters: Intents that target specific components must accurately match the target's intent-filter specifications. If you send an intent to launch another app's activity, the target intent component needs to align with the receiving activity's declared intent-filters.
• Intents must have actions: Intents without an action will no longer match any intent-filters. This means that intents used to start activities or services must have a clearly defined action.

In order to check how your app responds to these changes, use StrictMode in your app. To see detailed logs about Intent usage violations, add the following method:

fun onCreate() {
    StrictMode.setVmPolicy(VmPolicy.Builder()
        .detectUnsafeIntentLaunch()
        .build()
    )
}

public void onCreate() {
    StrictMode.setVmPolicy(new VmPolicy.Builder()
            .detectUnsafeIntentLaunch()
            .build());
}

用户体验和系统界面

Android 15 包含一些旨在打造更一致、更直观的用户体验的变更。

窗口边衬区变更

Android 15 中与窗口内边距相关的两项变更：默认强制执行边到边，此外还有配置变更，例如系统栏的默认配置。

全面实施政策

Apps are edge-to-edge by default on devices running Android 15 if the app is targeting Android 15 (API level 35).

This is a breaking change that might negatively impact your app's UI. The changes affect the following UI areas:

• Gesture handle navigation bar
  • Transparent by default.
  • Bottom offset is disabled so content draws behind the system navigation bar unless insets are applied.
  • setNavigationBarColor and R.attr#navigationBarColor are deprecated and don't affect gesture navigation.
  • setNavigationBarContrastEnforced and R.attr#navigationBarContrastEnforced continue to have no effect on gesture navigation.
• 3-button navigation
  • Opacity set to 80% by default, with color possibly matching the window background.
  • Bottom offset disabled so content draws behind the system navigation bar unless insets are applied.
  • setNavigationBarColor and R.attr#navigationBarColor are set to match the window background by default. The window background must be a color drawable for this default to apply. This API is deprecated but continues to affect 3-button navigation.
  • setNavigationBarContrastEnforced and R.attr#navigationBarContrastEnforced is true by default, which adds an 80% opaque background across 3-button navigation.
• Status bar
  • Transparent by default.
  • The top offset is disabled so content draws behind the status bar unless insets are applied.
  • setStatusBarColor and R.attr#statusBarColor are deprecated and have no effect on Android 15.
  • setStatusBarContrastEnforced and R.attr#statusBarContrastEnforced are deprecated but still have an effect on Android 15.
• Display cutout
  • layoutInDisplayCutoutMode of non-floating windows must be LAYOUT_IN_DISPLAY_CUTOUT_MODE_ALWAYS. SHORT_EDGES, NEVER, and DEFAULT are interpreted as ALWAYS so that users don't see a black bar caused by the display cutout and appear edge-to-edge.

The following example shows an app before and after targeting Android 15 (API level 35), and before and after applying insets. This example is not comprehensive, this might appear differently on Android Auto.

What to check if your app is already edge-to-edge

If your app is already edge-to-edge and applies insets, you are mostly unimpacted, except in the following scenarios. However, even if you think you aren't impacted, we recommend you test your app.

• You have a non-floating window, such as an Activity that uses SHORT_EDGES, NEVER or DEFAULT instead of LAYOUT_IN_DISPLAY_CUTOUT_MODE_ALWAYS. If your app crashes on launch, this might be due to your splashscreen. You can either upgrade the core splashscreen dependency to 1.2.0-alpha01 or later or set window.attributes.layoutInDisplayCutoutMode = WindowManager.LayoutInDisplayCutoutMode.always.
• There might be lower-traffic screens with occluded UI. Verify these less-visited screens don't have occluded UI. Lower-traffic screens include:
  • Onboarding or sign-in screens
  • Settings pages

What to check if your app is not already edge-to-edge

If your app is not already edge-to-edge, you are most likely impacted. In addition to the scenarios for apps that are already edge-to-edge, you should consider the following:

• If your app uses Material 3 Components ( androidx.compose.material3) in compose, such as TopAppBar, BottomAppBar, and NavigationBar, these components are likely not impacted because they automatically handle insets.
• If your app is using Material 2 Components ( androidx.compose.material) in Compose, these components don't automatically handle insets. However, you can get access to the insets and apply them manually. In androidx.compose.material 1.6.0 and later, use the windowInsets parameter to apply the insets manually for BottomAppBar, TopAppBar, BottomNavigation, and NavigationRail. Likewise, use the contentWindowInsets parameter for Scaffold.
• If your app uses views and Material Components (com.google.android.material), most views-based Material Components such as BottomNavigationView, BottomAppBar, NavigationRailView, or NavigationView, handle insets and require no additional work. However, you need to add android:fitsSystemWindows="true" if using AppBarLayout.
• For custom composables, apply the insets manually as padding. If your content is within a Scaffold, you can consume insets using the Scaffold padding values. Otherwise, apply padding using one of the WindowInsets.
• If your app is using views and BottomSheet, SideSheet or custom containers, apply padding using ViewCompat.setOnApplyWindowInsetsListener. For RecyclerView, apply padding using this listener and also add clipToPadding="false".

What to check if your app must offer custom background protection

If your app must offer custom background protection to 3-button navigation or the status bar, your app should place a composable or view behind the system bar using WindowInsets.Type#tappableElement() to get the 3-button navigation bar height or WindowInsets.Type#statusBars.

Additional edge-to-edge resources

See the Edge to Edge Views and Edge to Edge Compose guides for additional considerations on applying insets.

Deprecated APIs

The following APIs are deprecated but not disabled:

• R.attr#enforceStatusBarContrast
• R.attr#navigationBarColor (for 3 button navigation, with 80% alpha)
• Window#isStatusBarContrastEnforced
• Window#setNavigationBarColor (for 3 button navigation, with 80% alpha)
• Window#setStatusBarContrastEnforced

The following APIs are deprecated and disabled:

• R.attr#navigationBarColor (for gesture navigation)
• R.attr#navigationBarDividerColor
• R.attr#statusBarColor
• Window#setDecorFitsSystemWindows
• Window#getNavigationBarColor
• Window#getNavigationBarDividerColor
• Window#getStatusBarColor
• Window#setNavigationBarColor (for gesture navigation)
• Window#setNavigationBarDividerColor
• Window#setStatusBarColor

稳定配置

If your app targets Android 15 (API level 35) or higher, Configuration no longer excludes the system bars. If you use the screen size in the Configuration class for layout calculation, you should replace it with better alternatives like an appropriate ViewGroup, WindowInsets, or WindowMetricsCalculator depending on your need.

Configuration has been available since API 1. It is typically obtained from Activity.onConfigurationChanged. It provides information like window density, orientation, and sizes. One important characteristic about the window sizes returned from Configuration is that it previously excluded the system bars.

The configuration size is typically used for resource selection, such as /res/layout-h500dp, and this is still a valid use case. However, using it for layout calculation has always been discouraged. If you do so, you should move away from it now. You should replace the use of Configuration with something more suitable depending on your use case.

If you use it to calculate the layout, use an appropriate ViewGroup, such as CoordinatorLayout or ConstraintLayout. If you use it to determine the height of the system navbar, use WindowInsets. If you want to know the current size of your app window, use computeCurrentWindowMetrics.

The following list describes the fields affected by this change:

• Configuration.screenWidthDp and screenHeightDp sizes no longer exclude the system bars.
• Configuration.smallestScreenWidthDp is indirectly affected by changes to screenWidthDp and screenHeightDp.
• Configuration.orientation is indirectly affected by changes to screenWidthDp and screenHeightDp on close-to-square devices.
• Display.getSize(Point) is indirectly affected by the changes in Configuration. This was deprecated beginning in API level 30.
• Display.getMetrics() has already worked like this since API level 33.

elegantTextHeight 属性默认值为 true

对于以 Android 15（API 级别 35）为目标平台的应用，elegantTextHeight TextView 属性默认会变为 true，将默认使用的紧凑字体替换为一些具有较大垂直测量的脚本，使其更易于阅读。紧凑字体旨在防止布局中断；Android 13（API 级别 33）允许文本布局利用 fallbackLineSpacing 属性拉伸垂直高度，从而防止许多此类中断。

在 Android 15 中，系统中仍保留了紧凑字体，因此您的应用可以将 elegantTextHeight 设置为 false 以获得与之前相同的行为，但即将发布的版本不太可能支持此字体。因此，如果您的应用支持以下脚本：阿拉伯语、老挝语、缅甸语、泰米尔语、古吉拉特语、卡纳达语、马拉雅拉姆语、奥里亚语、泰卢固语或泰语，请将 elegantTextHeight 设置为 true 以测试您的应用。

TextView 宽度因复杂的字母形状而发生变化

在以前的 Android 版本中，某些具有复杂形状的手写字体或语言可能会在上一个或下一个字符的区域绘制字母。在某些情况下，此类字母会在开头或结尾处被剪裁。从 Android 15 开始，TextView 会分配宽度，以便为此类字母绘制足够的空间，并允许应用请求向左额外添加内边距以防止剪裁。

由于此更改会影响 TextView 确定宽度的方式，因此如果应用以 Android 15（API 级别 35）或更高版本为目标平台，TextView 会默认分配更多宽度。您可以通过对 TextView 调用 setUseBoundsForWidth API 来启用或停用此行为。

由于添加左内边距可能会导致现有布局未对齐，因此默认情况下不会添加内边距，即使以 Android 15 或更高版本为目标平台的应用也是如此。不过，您可以通过调用 setShiftDrawingOffsetForStartOverhang 添加额外的内边距以防止剪裁。

以下示例展示了这些更改如何改进某些字体和语言的文本布局。

采用手写体字体的英语文本的标准布局。部分字母被截断。对应的 XML 如下：

<TextView
    android:fontFamily="cursive"
    android:text="java" />

相同英语文本的布局，增加了宽度和内边距。以下是相应的 XML：

<TextView
    android:fontFamily="cursive"
    android:text="java"
    android:useBoundsForWidth="true"
    android:shiftDrawingOffsetForStartOverhang="true" />

泰语文本的标准布局。部分字母被截断。 以下是相应的 XML：

<TextView
    android:text="คอมพิวเตอร์" />

相同泰语文本的布局，增加了宽度和内边距。以下是相应的 XML：

<TextView
    android:text="คอมพิวเตอร์"
    android:useBoundsForWidth="true"
    android:shiftDrawingOffsetForStartOverhang="true" />

EditText 的语言区域感知默认行高

在较低版本的 Android 中，文本布局会拉伸文本的高度，以满足与当前语言区域匹配的字体的行高。例如，如果内容是日语，由于日语字体的行高略高于拉丁字体，因此文本的高度会略高。不过，尽管行高存在这些差异，但无论使用的是哪种语言区域，EditText 元素的大小都是统一的，如下图所示：

对于以 Android 15（API 级别 35）为目标平台的应用，现在为 EditText 预留了最小行高，以匹配指定语言区域的参考字体，如下图所示：

如有需要，您的应用可以将 useLocalePreferredLineHeightForMinimum 属性指定为 false，以恢复之前的行为；您的应用还可以在 Kotlin 和 Java 中使用 setMinimumFontMetrics API 设置自定义最小垂直指标。

摄像头和媒体

Android 15 对以 Android 15 或更高版本为目标平台的应用的相机和媒体行为做出了以下更改。

有关请求音频焦点的限制

以 Android 15（API 级别 35）为目标平台的应用必须是顶部应用或正在运行前台服务，才能请求音频焦点。如果应用在未满足上述任一要求的情况下尝试请求焦点，调用将返回 AUDIOFOCUS_REQUEST_FAILED。

如需详细了解音频焦点，请参阅管理音频焦点。

更新后的非 SDK 限制

Android 15 包含更新后的受限非 SDK 接口列表（基于与 Android 开发者之间的协作以及最新的内部测试）。在限制使用非 SDK 接口之前，我们会尽可能确保有可用的公开替代方案。

如果您的应用并非以 Android 15 为目标平台，其中一些变更可能不会立即对您产生影响。不过，虽然您的应用可以访问某些非 SDK 接口（具体取决于应用的目标 API 级别），但只要您使用任何非 SDK 方法或字段，终归存在导致应用出问题的显著风险。

如果您不确定自己的应用是否使用了非 SDK 接口，则可以测试该应用，进行确认。如果您的应用依赖于非 SDK 接口，则应该开始计划迁移到 SDK 替代方案。不过，我们知道某些应用具有使用非 SDK 接口的有效用例。如果您无法为应用中的某项功能找到使用非 SDK 接口的替代方案，则应该请求新的公共 API。

如需详细了解此 Android 版本中的变更，请参阅 Android 15 中有关限制非 SDK 接口的更新。如需全面了解有关非 SDK 接口的详细信息，请参阅对非 SDK 接口的限制。