行为变更：以 Android 16 或更高版本为目标平台的应用

与早期版本一样，Android 16 包含一些行为变更，这些变更可能会影响您的应用。以下行为变更仅影响以 Android 16 或更高版本为目标平台的应用。如果您的应用以 Android 16 或更高版本为目标平台，您应该修改自己的应用以支持这些行为（如果适用）。

请务必查看对 Android 16 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）。

用户体验和系统界面

Android 16 进行了以下变更，旨在打造更一致、更直观的用户体验。

无边框设计停用退出选项

Android 15 enforced edge-to-edge for apps targeting Android 15 (API level 35), but your app could opt-out by setting R.attr#windowOptOutEdgeToEdgeEnforcement to true. For apps targeting Android 16, R.attr#windowOptOutEdgeToEdgeEnforcement is deprecated and disabled, and your app can't opt-out of going edge-to-edge.

For testing in Android 16 Beta 2, ensure your app supports edge-to-edge and remove any use of R.attr#windowOptOutEdgeToEdgeEnforcement. To support edge-to-edge, see the Compose and Views guidance. Let us know about concerns in our issue tracker on the feedback page.

必须迁移或停用预测性返回

For apps targeting Android 16 or higher and running on an Android 16 or higher device, the predictive back system animations (back-to-home, cross-task, and cross-activity) are enabled by default. Additionally, onBackPressed is not called and KeyEvent.KEYCODE_BACK is not dispatched anymore.

If your app intercepts the back event and you haven't migrated to predictive back yet, update your app to use supported back navigation APIs. or temporarily opt out by setting the android:enableOnBackInvokedCallback attribute to false in the <application> or <activity> tag of your app's AndroidManifest.xml file.

优雅字体 API 已废弃并停用

Apps targeting Android 15 (API level 35) have the elegantTextHeight TextView attribute set to true by default, replacing the compact font with one that is much more readable. You could override this by setting the elegantTextHeight attribute to false.

Android 16 deprecates the elegantTextHeight attribute, and the attribute will be ignored once your app targets Android 16. The "UI fonts" controlled by these APIs are being discontinued, so you should adapt any layouts to ensure consistent and future proof text rendering in Arabic, Lao, Myanmar, Tamil, Gujarati, Kannada, Malayalam, Odia, Telugu or Thai.

核心功能

Android 16 包含以下更改，用于修改或扩展 Android 系统的各种核心功能。

固定费率工作调度优化

Prior to targeting Android 16, when scheduleAtFixedRate missed a task execution due to being outside a valid process lifecycle, all missed executions immediately execute when the app returns to a valid lifecycle.

When targeting Android 16, at most one missed execution of scheduleAtFixedRate is immediately executed when the app returns to a valid lifecycle. This behavior change is expected to improve app performance. Test this behavior in your app to check if your app is impacted. You can also test by using the app compatibility framework and enabling the STPE_SKIP_MULTIPLE_MISSED_PERIODIC_TASKS compat flag.

设备规格

Android 16 对在大屏设备上显示的应用做出了以下更改。

自适应布局

With Android apps now running on a variety of devices (such as phones, tablets, foldables, desktops, cars, and TVs) and windowing modes on large screens (such as split screen and desktop windowing), developers should build Android apps that adapt to any screen and window size, regardless of device orientation. Paradigms like restricting orientation and resizability are too restrictive in today's multidevice world.

Ignore orientation, resizability, and aspect ratio restrictions

For apps targeting Android 16, Android 16 includes changes to how the system manages orientation, resizability, and aspect ratio restrictions. On displays with smallest width >= 600dp, the restrictions no longer apply. Apps also fill the entire display window, regardless of aspect ratio or a user's preferred orientation, and pillarboxing isn't used.

This change introduces a new standard platform behavior. Android is moving toward a model where apps are expected to adapt to various orientations, display sizes, and aspect ratios. Restrictions like fixed orientation or limited resizability hinder app adaptability, so we recommend making your app adaptive to deliver the best possible user experience.

You can also test this behavior by using the [app compatibility framework][a16-kilo-14] and enabling the UNIVERSAL_RESIZABLE_BY_DEFAULT compat flag.

Common breaking changes

Ignoring orientation, resizability, and aspect ratio restrictions might impact your app's UI on some devices, especially elements that were designed for small layouts locked in portrait orientation: for example, issues like stretched layouts and off-screen animations and components. Any assumptions about aspect ratio or orientation can cause visual issues with your app. Learn more about how to avoid them and improve your app's adaptive behaviour.

Allowing device rotation results in more activity re-creation, which can result in losing user state if not properly preserved. Learn how to correctly save UI state in Save UI states.

Implementation details

The following manifest attributes and runtime APIs are ignored across large screen devices in full-screen and multi-window modes:

• screenOrientation
• resizableActivity
• minAspectRatio
• maxAspectRatio
• setRequestedOrientation()
• getRequestedOrientation()

The following values for screenOrientation, setRequestedOrientation(), and getRequestedOrientation() are ignored:

• portrait
• reversePortrait
• sensorPortrait
• userPortrait
• landscape
• reverseLandscape
• sensorLandscape
• userLandscape

Regarding display resizability, android:resizeableActivity="false", android:minAspectRatio, and android:maxAspectRatio have no effect.

For apps targeting Android 16, app orientation, resizability, and aspect ratio constraints are ignored on large screens by default, but every app that isn't fully ready can temporarily override this behavior by opting out (which results in the previous behavior of being placed in compatibility mode).

Exceptions

The Android 16 orientation, resizability, and aspect ratio restrictions don't apply in the following situations:

• Games (based on the android:appCategory flag)
• Users explicitly opting in to the app's default behavior in aspect ratio settings of the device
• Screens that are smaller than sw600dp

Opt out temporarily

To opt out a specific activity, declare the PROPERTY_COMPAT_ALLOW_RESTRICTED_RESIZABILITY manifest property:

<activity ...>
  <property android:name="android.window.PROPERTY_COMPAT_ALLOW_RESTRICTED_RESIZABILITY" android:value="true" />
  ...
</activity>

If too many parts of your app aren't ready for Android 16, you can opt out completely by applying the same property at the application level:

<application ...>
  <property android:name="android.window.PROPERTY_COMPAT_ALLOW_RESTRICTED_RESIZABILITY" android:value="true" />
</application>

健康与健身

Android 16 包含与健康与健身数据相关的以下变更。

健康与健身权限

对于以 Android 16 或更高版本为目标平台的应用，BODY_SENSORS 权限即将过渡到 android.permissions.health 下的精细权限，这些权限也会被 Health Connect 使用。凡是以前需要具有 BODY_SENSORS 或 BODY_SENSORS_BACKGROUND 权限的 API，现在都需要获取相应的 android.permissions.health 权限。这会影响以下数据类型、API 和前台服务类型：

• 来自 Wear 健康服务的 HEART_RATE_BPM
• Android Sensor Manager 中的 Sensor.TYPE_HEART_RATE
• Wear ProtoLayout 中的 heartRateAccuracy 和 heartRateBpm
• FOREGROUND_SERVICE_TYPE_HEALTH，其中需要使用相应的 android.permission.health 权限来替代 BODY_SENSORS

如果您的应用使用这些 API，则现在应请求相应的精细权限：

• 如需在使用期间监测心率、血氧饱和度或体表温度：请请求 android.permissions.health 下的精细权限，例如 READ_HEART_RATE，而不是 BODY_SENSORS。
• 对于后台传感器访问权限：请求 READ_HEALTH_DATA_IN_BACKGROUND，而不是 BODY_SENSORS_BACKGROUND。

这些权限与用于保护对 Health Connect（用于存储健康、健身和身心健康数据的 Android 数据存储区）读取数据的权限相同。

移动应用

迁移到使用 READ_HEART_RATE 和其他精细权限的移动应用还必须声明 activity 以显示应用的隐私权政策。这与 Health Connect 的要求相同。

连接

Android 16 在蓝牙堆栈中进行了以下更改，以改善与外围设备的连接。

用于处理键绑定丢失和加密更改的新 intent

As part of the Improved bond loss handling, Android 16 also introduces 2 new intents to provide apps with greater awareness of bond loss and encryption changes.

Apps targeting Android 16 can now:

• Receive an ACTION_KEY_MISSING intent when remote bond loss is detected, allowing them to provide more informative user feedback and take appropriate actions.
• Receive an ACTION_ENCRYPTION_CHANGE intent whenever encryption status of the link changes. This includes encryption status change, encryption algorithm change, and encryption key size change. Apps must consider the bond restored if the link is successfully encrypted upon receiving ACTION_ENCRYPTION_CHANGE intent later.

If your app currently uses custom mechanisms for bond loss handling, migrate to the new intent ACTION_KEY_MISSING to detect and manage bond loss events. We recommend your app guide the user to confirm the remote device is in range before initiating device forgetting and re-pairing.

Moreover, if a device disconnects after ACTION_KEY_MISSING intent is received, your app should be mindful about reconnecting to the device as that device may no longer be bonded with the system.