行为变更：以 Android 16 或更高版本为目标平台的应用

与之前的版本一样，Android 16 包含一些可能会影响应用的行为变更。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，则应根据情况修改应用，以支持这些行为。

无论应用的 targetSdkVersion 为何，都请务必查看对 Android 16 上运行的所有应用都有影响的行为变更列表。

用户体验和系统界面

Android 16（API 级别 36）包含以下旨在打造更一致、更直观的用户体验的变更。

无边框设计选择停用功能即将停用

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 (API level 36), R.attr#windowOptOutEdgeToEdgeEnforcement is deprecated and disabled, and your app can't opt-out of going edge-to-edge.

• If your app targets Android 16 (API level 36) and is running on an Android 15 device, R.attr#windowOptOutEdgeToEdgeEnforcement continues to work.
• If your app targets Android 16 (API level 36) and is running on an Android 16 device, R.attr#windowOptOutEdgeToEdgeEnforcement is disabled.

For testing in Android 16, ensure your app supports edge-to-edge and remove any use of R.attr#windowOptOutEdgeToEdgeEnforcement so that your app also supports edge-to-edge on an Android 15 device. To support edge-to-edge, see the Compose and Views guidance.

预测性返回需要迁移或选择停用

对于以 Android 16（API 级别 36）或更高版本为目标平台且在搭载 Android 16 或更高版本的设备上运行的应用，预测性返回系统动画（返回主屏幕、跨任务和跨 activity）默认处于启用状态。此外，系统不再调用 onBackPressed，也不再调度 KeyEvent.KEYCODE_BACK。

如果您的应用会拦截返回事件，但您尚未迁移到预测性返回，请更新应用以使用受支持的返回导航 API，或者通过在应用的 AndroidManifest.xml 文件的 <application> 或 <activity> 标记中将 android:enableOnBackInvokedCallback 属性设置为 false 来暂时选择停用。

预测性返回主页动画。

预测性跨 activity 动画。

预测性跨任务动画。

优雅字体 API 已弃用并停用

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.

elegantTextHeight behavior for apps targeting Android 14 (API level 34) and lower, or for apps targeting Android 15 (API level 35) that overrode the default by setting the elegantTextHeight attribute to false.

elegantTextHeight behavior for apps targeting Android 16 (API level 36), or for apps targeting Android 15 (API level 35) that didn't override the default by setting the elegantTextHeight attribute to false.

核心功能

Android 16（API 级别 36）包含以下变更，这些变更会修改或扩展 Android 系统的各种核心功能。

固定费率工作安排优化

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（API 级别 36）在应用显示在大屏设备上时，包含以下变更。

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 (API level 36), orientation, resizability, and aspect ratio restrictions no longer apply on displays with smallest width >= 600dp. Apps 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. Make your app adaptive to deliver the best possible user experience.

You can also test this behavior by using the app compatibility framework 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 (API level 36), 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>

Important: The opt-out is temporary and won't apply when targeting API level 37 in a future Android release. That is, for apps targeting API level 37, orientation, resizability, and aspect ratio restrictions are ignored on displays that are at least sw600dp.

健康与健身

Android 16（API 级别 36）包含与健康和健身数据相关的以下变更。

健康与健身权限

对于以 Android 16（API 级别 36）或更高版本为目标平台的应用，BODY_SENSORS 权限使用 android.permissions.health 下更精细的权限，健康数据共享也使用这些权限。自 Android 16 起，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：

• 从 Wear OS 上的健康服务中获取 HEART_RATE_BPM
• 来自 Android Sensor Manager 的 Sensor.TYPE_HEART_RATE
• 在 Wear OS 上，ProtoLayout 中的 heartRateAccuracy 和 heartRateBpm
• FOREGROUND_SERVICE_TYPE_HEALTH，其中需要使用相应的 android.permission.health 权限来代替 BODY_SENSORS

如果您的应用使用这些 API，则应请求相应的精细权限：

• 对于使用期间的心率、血氧饱和度或体表温度监测：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（Android 健康、健身和身心状态数据存储区）中读取数据的访问权限相同。

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。此要求与健康数据共享的要求相同。

重要提示： 如果未能提供移动应用使用相关权限的理由，相应权限将被撤消。

连接

Android 16（API 级别 36）在蓝牙堆栈中进行了以下更改，以改善与外围设备的连接。

用于处理绑定丢失和加密更改的新 intent

作为改进了对键值对丢失的处理的一部分，Android 16 还引入了 2 个新 intent，以便应用更好地了解键值对丢失和加密更改。

以 Android 16 为目标平台的应用现在可以：

• 在检测到远程键盘连接丢失时接收 ACTION_KEY_MISSING intent，以便提供更具信息量的用户反馈并采取适当的措施。
• 每当链接的加密状态发生变化时，都会收到 ACTION_ENCRYPTION_CHANGE intent。这包括加密状态更改、加密算法更改和加密密钥大小更改。如果应用在稍后收到 ACTION_ENCRYPTION_CHANGE intent 时成功加密了链接，则必须将该绑定视为已恢复。

适应不同的 OEM 实现

虽然 Android 16 引入了这些新 intent，但其实现和广播可能会因不同的设备制造商 (OEM) 而异。为了确保您的应用在所有设备上都能提供一致且可靠的体验，开发者应设计其绑定丢失处理机制，以妥善适应这些潜在的变化。

我们建议您采用以下应用行为：

• 如果广播 ACTION_KEY_MISSING intent：

  系统会断开 ACL（异步无连接）链接，但会保留设备的配对信息（如此处所述）。

  您的应用应将此 intent 用作检测配对丢失的主要信号，并在发起设备忘记或重新配对之前引导用户确认远程设备是否在范围内。

  如果设备在收到 ACTION_KEY_MISSING 后断开连接，您的应用应谨慎重新连接，因为设备可能已不再与系统绑定。

• 如果未广播 ACTION_KEY_MISSING intent：

  ACL 链接将保持连接状态，系统会移除设备的配对信息，与 Android 15 中的行为相同。

  在这种情况下，您的应用应继续使用与之前的 Android 版本相同的现有配对丢失处理机制，以检测和管理配对丢失事件。

移除蓝牙绑定的新方法

现在，以 Android 16 为目标平台的所有应用都可以使用 CompanionDeviceManager 中的公共 API 解除蓝牙设备配对。如果配套设备作为 CDM 关联进行管理，则应用可以在关联的设备上使用新的 removeBond(int) API 触发蓝牙配对的移除。该应用可以通过监听蓝牙设备广播事件 ACTION_BOND_STATE_CHANGED 来监控配对状态变化。

安全

Android 16（API 级别 36）包含以下安全方面的变更。

MediaStore 版本锁定

对于以 Android 16 或更高版本为目标平台的应用，MediaStore#getVersion() 现在将是每个应用的唯一标识。这会从版本字符串中移除标识属性，以防止滥用和用于指纹识别技术。应用不应对此版本的格式做出任何假设。在使用此 API 时，应用应已处理版本变更，并且在大多数情况下无需更改其当前行为，除非开发者尝试推断超出此 API 预期范围的其他信息。

更安全的 intent

The Safer Intents feature is a multi-phase security initiative designed to improve the security of Android's intent resolution mechanism. The goal is to protect apps from malicious actions by adding checks during intent processing and filtering intents that don't meet specific criteria.

In Android 15 the feature focused on the sending app, now with Android 16, shifts control to the receiving app, allowing developers to opt-in to strict intent resolution using their app manifest.

Two key changes are being implemented:

1. Explicit Intents Must Match the Target Component's Intent Filter: If an intent explicitly targets a component, it should match that component's intent filter.

2. Intents Without an Action Cannot Match any Intent Filter: Intents that don't have an action specified shouldn't be resolved to any intent filter.

These changes only apply when multiple apps are involved and don't affect intent handling within a single app.

Impact

The opt-in nature means that developers must explicitly enable it in their app manifest for it to take effect. As a result, the feature's impact will be limited to apps whose developers:

• Are aware of the Safer Intents feature and its benefits.
• Actively choose to incorporate stricter intent handling practices into their apps.

This opt-in approach minimizes the risk of breaking existing apps that may rely on the current less-secure intent resolution behavior.

While the initial impact in Android 16 may be limited, the Safer Intents initiative has a roadmap for broader impact in future Android releases. The plan is to eventually make strict intent resolution the default behavior.

The Safer Intents feature has the potential to significantly enhance the security of the Android ecosystem by making it more difficult for malicious apps to exploit vulnerabilities in the intent resolution mechanism.

However, the transition to opt-out and mandatory enforcement must be carefully managed to address potential compatibility issues with existing apps.

Implementation

Developers need to explicitly enable stricter intent matching using the intentMatchingFlags attribute in their app manifest. Here is an example where the feature is opt-in for the entire app, but disabled/opt-out on a receiver:

<application android:intentMatchingFlags="enforceIntentFilter">
    <receiver android:name=".MyBroadcastReceiver" android:exported="true" android:intentMatchingFlags="none">
        <intent-filter>
            <action android:name="com.example.MY_CUSTOM_ACTION" />
        </intent-filter>
        <intent-filter>
            <action android:name="com.example.MY_ANOTHER_CUSTOM_ACTION" />
        </intent-filter>
    </receiver>
</application>

Note: The attribute can be specified on the <application> tag as well as at the component tags such as <activity>, <activity-alias>, <receiver>, <service>, <provider> and the attribute on the component can be used to override what's on the <application> tag

More on the supported flags:

Flag Name	Description
enforceIntentFilter	Enforces stricter matching for incoming intents
none	Disables all special matching rules for incoming intents. When specifying multiple flags, conflicting values are resolved by giving precedence to the "none" flag
allowNullAction	Relaxes the matching rules to allow intents without an action to match. This flag to be used in conjunction with "enforceIntentFilter" to achieve a specific behavior

Testing and Debugging

When the enforcement is active, apps should function correctly if the intent caller has properly populated the intent. However, blocked intents will trigger warning log messages like "Intent does not match component's intent filter:" and "Access blocked:" with the tag "PackageManager." This indicates a potential issue that could impact the app and requires attention.

Logcat filter:

tag=:PackageManager & (message:"Intent does not match component's intent filter:" | message: "Access blocked:")

GPU 系统调用过滤

为了加固 Mali GPU 表面，在正式版 build 中，已弃用或仅用于 GPU 开发的 Mali GPU IOCTL 已被屏蔽。此外，用于 GPU 性能分析的 IOCTL 已限制为 shell 进程或可调试的应用。如需详细了解平台级政策，请参阅 SAC 更新。

此变化发生在使用 Mali GPU 的 Pixel 设备（Pixel 6-9）上。Arm 已在其 r54p2 版本的 Documentation/ioctl-categories.rst 中提供了 IOCTL 的官方分类。此列表将在未来的驱动程序版本中继续维护。

此项变更不会影响受支持的图形 API（包括 Vulkan 和 OpenGL），预计也不会影响开发者或现有应用。 Streamline Performance Analyzer 和 Android GPU 检查器等 GPU 性能剖析工具不会受到影响。

测试

如果您看到类似如下所示的 SELinux 拒绝，则说明您的应用可能受到了此变更的影响：

06-30 10:47:18.617 20360 20360 W roidJUnitRunner: type=1400 audit(0.0:85): avc:  denied  { ioctl }
for  path="/dev/mali0" dev="tmpfs" ino=1188 ioctlcmd=0x8023
scontext=u:r:untrusted_app_25:s0:c512,c768 tcontext=u:object_r:gpu_device:s0 tclass=chr_file
permissive=0 app=com.google.android.selinux.pts

如果您的应用需要使用被屏蔽的 IOCTL，请提交 bug 并将其分配给 [e-mail]。

常见问题解答

1. 此政策变更是否适用于所有原始设备制造商 (OEM)？ 此变更将采用选择启用模式，但任何想要使用此强化方法的原始设备制造商 (OEM) 都可以使用。如需了解如何实现此变更，请参阅实现文档。

2. 是否必须在 OEM 代码库中进行更改才能实现此功能，还是默认随新的 AOSP 版本提供？ 平台级变更将默认随新的 AOSP 版本一起发布。如果供应商想要应用此变更，可以在其代码库中选择启用此变更。

3. SoC 是否负责使 IOCTL 列表保持最新状态？例如，如果我的设备使用 ARM Mali GPU，我是否需要就任何更改与 ARM 联系？ 各个 SoC 必须在驱动程序发布后根据设备更新其 IOCTL 列表。 例如，ARM 会在驱动程序更新时更新其已发布的 IOCTL 列表。 不过，OEM 应确保在 SEPolicy 中纳入这些更新，并根据需要将任何选定的自定义 IOCTL 添加到列表中。

4. 此变更是否会自动应用于所有在售 Pixel 设备，还是需要用户执行操作来切换某些设置才能应用此变更？ 此变更适用于所有使用 Mali GPU 的 Pixel 在售设备（Pixel 6-9）。用户无需采取任何行动即可应用此变更。

5. 使用此政策会影响内核驱动程序的性能吗？ 我们使用 GFXBench 在 Mali GPU 上测试了此政策，未发现 GPU 性能有任何可衡量的变化。

6. IOCTL 列表是否需要与当前的用户空间和内核驱动程序版本保持一致？ 是的，允许的 IOCTL 列表必须与用户空间和内核驱动程序支持的 IOCTL 同步。如果用户空间或内核驱动程序中的 IOCTL 发生更新，则必须更新 SEPolicy IOCTL 列表以保持一致。

7. ARM 已将 IOCTL 分类为“受限”/“检测”，但我们希望在生产用例中使用其中一些，并拒绝其他 IOCTL。 各个 OEM/SoC 负责根据其用户空间 Mali 库的配置来决定如何对其使用的 IOCTL 进行分类。ARM 的列表可用于帮助确定这些值，但每个 OEM/SoC 的使用情形可能有所不同。

隐私权

Android 16（API 级别 36）包含以下隐私权方面的变更。

本地网络权限

Devices on the LAN can be accessed by any app that has the INTERNET permission. This makes it easy for apps to connect to local devices but it also has privacy implications such as forming a fingerprint of the user, and being a proxy for location.

The Local Network Protections project aims to protect the user's privacy by gating access to the local network behind a new runtime permission.

Release plan

This change will be deployed between two releases, 25Q2 and 26Q2 respectively. It is imperative that developers follow this guidance for 25Q2 and share feedback because these protections will be enforced at a later Android release. Moreover, they will need to update scenarios which depend on implicit local network access by using the following guidance and prepare for user rejection and revocation of the new permission.

Impact

At the current stage, LNP is an opt-in feature which means only the apps that opt in will be affected. The goal of the opt-in phase is for app developers to understand which parts of their app depend on implicit local network access such that they can prepare to permission guard them for the next release.

Apps will be affected if they access the user's local network using:

• Direct or library use of raw sockets on local network addresses (e.g. mDNS or SSDP service discovery protocol)
• Use of framework level classes that access the local network (e.g. NsdManager)

Traffic to and from a local network address requires local network access permission. The following table lists some common cases:

App Low Level Network Operation	Local Network Permission Required
Making an outgoing TCP connection	yes
Accepting incoming TCP connections	yes
Sending a UDP unicast, multicast, broadcast	yes
Receiving an incoming UDP unicast, multicast, broadcast	yes

These restrictions are implemented deep in the networking stack, and thus they apply to all networking APIs. This includes sockets created in native or managed code, networking libraries like Cronet and OkHttp, and any APIs implemented on top of those. Trying to resolve services on the local network (i.e. those with a .local suffix) will require local network permission.

Note: Traffic originating from Android Webviews that require local network access will inherit permission state from the host app

Exceptions to the rules above:

• If a device's DNS server is on a local network, traffic to or from it (at port 53) doesn't require local network access permission.
• Applications using Output Switcher as their in-app picker won't need local network permissions (more guidance to come in 2025Q4).

Note: Many media casting scenarios depend on access to the local network and will be impacted by this change. However, not all apps which offer casting will need to request the new permission. Future APIs and guidance for dealing with casting scenarios will be provided in 25Q4.

Developer Guidance (Opt-in)

To opt into local network restrictions, do the following:

1. Flash the device to a build with 25Q2 Beta 3 or later.
2. Install the app to be tested.

3. Toggle the Appcompat flag in adb:

   adb shell am compat enable RESTRICT_LOCAL_NETWORK <package_name>
   

4. Reboot The device

Now your app's access to the local network is restricted and any attempt to access the local network will lead to socket errors. If you are using APIs that perform local network operations outside of your app process (ex: NsdManager), they won't be impacted during the opt-in phase.

To restore access, you must grant your app permission to NEARBY_WIFI_DEVICES.

1. Ensure the app declares the NEARBY_WIFI_DEVICES permission in its manifest.
2. Go to Settings > Apps > [Application Name] > Permissions > Nearby devices > Allow.

Note: In a future Android release, this feature will be guarded by a new permission in the Nearby devices permission group

Now your app's access to the local network should be restored and all your scenarios should work as they did prior to opting the app in.

Once enforcement for local network protection begins, here is how the app network traffic will be impacted.

Permission	Outbound LAN Request	Outbound/Inbound Internet Request	Inbound LAN Request
Granted	Works	Works	Works
Not Granted	Fails	Works	Fails

Use the following command to toggle-off the App-Compat flag

adb shell am compat disable RESTRICT_LOCAL_NETWORK <package_name>

Errors

Errors arising from these restrictions will be returned to the calling socket whenever it invokes send or a send variant to a local network address.

Example errors:

sendto failed: EPERM (Operation not permitted)

sendto failed: ECONNABORTED (Operation not permitted)

Local Network Definition

A local network in this project refers to an IP network that utilizes a broadcast-capable network interface, such as Wi-Fi or Ethernet, but excludes cellular (WWAN) or VPN connections.

The following are considered local networks:

IPv4:

• 169.254.0.0/16 // Link Local
• 100.64.0.0/10 // CGNAT
• 10.0.0.0/8 // RFC1918
• 172.16.0.0/12 // RFC1918
• 192.168.0.0/16 // RFC1918

IPv6:

• Link-local
• Directly-connected routes
• Stub networks like Thread
• Multiple-subnets (TBD)

Additionally, both multicast addresses (224.0.0.0/4, ff00::/8) and the IPv4 broadcast address (255.255.255.255) are classified as local network addresses.

应用拥有的照片

When prompted for photo and video permissions by an app targeting SDK 36 or higher on devices running Android 16 or higher, users who choose to limit access to selected media will see any photos owned by the app pre-selected in the photo picker. Users can deselect any of these pre-selected items, which will revoke the app's access to those photos and videos.