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（API 级别 36）包含以下变更，旨在打造更一致、更直观的用户体验。

无边框设计选择退出功能即将停用

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

For apps targeting Android 16 (API level 36) 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.

The predictive back-to-home animation.

The predictive cross-activity animation.

The predictive cross-task animation.

优雅字体 API 已弃用并停用

以 Android 15（API 级别 35）为目标平台的应用默认将 elegantTextHeight TextView 属性设置为 true，从而将紧凑型字体替换为可读性更高的字体。您可以通过将 elegantTextHeight 属性设置为 false 来替换此设置。

Android 16 弃用了 elegantTextHeight 属性，当您的应用以 Android 16 为目标平台后，系统会忽略该属性。由这些 API 控制的“界面字体”即将停用，因此您应调整所有布局，以确保阿拉伯语、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、泰卢固语或泰语文本的呈现效果一致且不受未来变化的影响。

针对以 Android 14（API 级别 34）及更低版本为目标平台的应用，或针对以 Android 15（API 级别 35）为目标平台且通过将 elegantTextHeight 属性设置为 false 替换默认值的应用，

elegantTextHeight 行为。

以 Android 16（API 级别 36）为目标平台的应用，或以 Android 15（API 级别 35）为目标平台但未通过将 elegantTextHeight 属性设置为 false 来替换默认值的应用，其

elegantTextHeight 行为。

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

现在，Android 应用可在各种设备（例如手机、平板电脑、可折叠设备、桌面设备、汽车和电视）上运行，并且在大屏设备上支持多种窗口模式（例如分屏和桌面窗口），因此开发者应构建能够适应任何屏幕和窗口尺寸的 Android 应用，无论设备方向如何。在当今多设备的世界中，限制屏幕方向和尺寸可调整性等范式过于严格。

忽略屏幕方向、尺寸可调整性和宽高比限制

对于以 Android 16（API 级别 36）为目标平台的应用，Android 16 包含对系统管理屏幕方向、尺寸调整能力和宽高比限制的方式的变更。在最小宽度大于或等于 600dp 的显示屏上，这些限制不再适用。应用还会填满整个显示窗口，无论宽高比或用户偏好的屏幕方向如何，都不会使用竖条模式。

此变更引入了新的标准平台行为。Android 正在向一种模型转变，在该模型中，应用需要适应各种屏幕方向、显示大小和宽高比。固定屏幕方向或有限的尺寸可调整性等限制会阻碍应用的适应性，因此我们建议让应用具备自适应能力，以提供尽可能出色的用户体验。

您还可以使用应用兼容性框架并启用 UNIVERSAL_RESIZABLE_BY_DEFAULT 兼容性标志来测试此行为。

常见的重大更改

忽略屏幕方向、可调整大小性和宽高比限制可能会影响应用在某些设备上的界面，尤其是那些专为锁定为纵向的小布局设计的元素，例如布局拉伸、动画和组件超出屏幕等问题。任何关于宽高比或屏幕方向的假设都可能导致应用出现视觉问题。详细了解如何避免这些问题并改进应用的自适应行为。

允许设备旋转会导致更多 activity 重新创建，如果未正确保留，可能会导致用户状态丢失。如需了解如何正确保存界面状态，请参阅保存界面状态。

实现细节

在全屏模式和多窗口模式下，以下清单属性和运行时 API 会被大屏设备忽略：

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

系统会忽略 screenOrientation、setRequestedOrientation() 和 getRequestedOrientation() 的以下值：

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

对于显示屏可调整大小性，android:resizeableActivity="false"、android:minAspectRatio 和 android:maxAspectRatio 没有影响。

对于以 Android 16（API 级别 36）为目标平台的应用，默认情况下，大屏设备会忽略应用屏幕方向、可调整尺寸性和宽高比限制，但尚未完全准备就绪的每个应用都可以选择停用此行为，从而暂时替换此行为（这会导致应用采用之前的行为，即放置在兼容模式下）。

异常

在以下情况下，Android 16 的屏幕方向、尺寸调整能力和宽高比限制不适用：

• 游戏（基于 android:appCategory 标志）
• 用户在设备的宽高比设置中明确选择启用应用的默认行为
• 小于 sw600dp 的屏幕

暂时停用

如需选择停用特定 activity，请声明 PROPERTY_COMPAT_ALLOW_RESTRICTED_RESIZABILITY 清单属性：

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

如果您的应用有太多部分尚未准备好支持 Android 16，您可以在应用级别应用相同的属性，从而完全选择不启用该功能：

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

重要提示： 此选择停用是临时性的，在未来的 Android 版本中以 API 级别 37 为目标平台时，此选择停用将不再适用。也就是说，对于以 API 级别 37 为目标的应用，在至少为 sw600dp 的显示屏上，系统会忽略屏幕方向、尺寸可调整性和宽高比限制。

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 BODY_SENSORS 或 BODY_SENSORS_BACKGROUND 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：

• HEART_RATE_BPM 来自 Wear OS 健康服务
• 来自 Android 传感器管理器的 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）中数据的读取访问权限相同。

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的合理用途，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

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.

Adapting to varying OEM implementations

While Android 16 introduces these new intents, their implementation and broadcasting can vary across different device manufacturers (OEMs). To ensure your app provides a consistent and reliable experience across all devices, developers should design their bond loss handling to gracefully adapt to these potential variations.

We recommend the following app behaviors:

• If the ACTION_KEY_MISSING intent is broadcast:

  The ACL (Asynchronous Connection-Less) link will be disconnected by the system, but the bond information for the device will be retained (as described here).

  Your app should use this intent as the primary signal for bond loss detection and guiding the user to confirm the remote device is in range before initiating device forgetting or re-pairing.

  If a device disconnects after ACTION_KEY_MISSING is received, your app should be cautious about reconnecting, as the device may no longer be bonded with the system.

• If the ACTION_KEY_MISSING intent is NOT broadcast:

  The ACL link will remain connected, and the bond information for the device will be removed by the system, same to behavior in Android 15.

  In this scenario, your app should continue its existing bond loss handling mechanisms as in previous Android releases, to detect and manage bond loss events.

移除蓝牙绑定的新方式

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

For apps targeting Android 16 or higher, MediaStore#getVersion() will now be unique to each app. This eliminates identifying properties from the version string to prevent abuse and usage for fingerprinting techniques. Apps shouldn't make any assumptions around the format of this version. Apps should already handle version changes when using this API and in most cases shouldn't need to change their current behavior, unless the developer has attempted to infer additional information that is beyond the intended scope of this API.

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

To harden the Mali GPU surface, Mali GPU IOCTLs that have been deprecated or are intended solely for GPU development have been blocked in production builds. Additionally, IOCTLs used for GPU profiling have been restricted to the shell process or debuggable applications. Refer to the SAC update for more details on the platform-level policy.

This change takes place on Pixel devices using the Mali GPU (Pixel 6-9). Arm has provided official categorization of their IOCTLs in Documentation/ioctl-categories.rst of their r54p2 release. This list will continue to be maintained in future driver releases.

This change does not impact supported graphics APIs (including Vulkan and OpenGL), and is not expected to impact developers or existing applications. GPU profiling tools such as the Streamline Performance Analyzer and the Android GPU Inspector won't be affected.

Testing

If you see a SELinux denial similar to the following, it is likely your application has been impacted by this change:

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

If your application needs to use blocked IOCTLs, please file a bug and assign it to [e-mail].

FAQ

1. Does this policy change apply to all OEMs? This change will be opt-in, but available to any OEMs who would like to use this hardening method. Instructions for implementing the change can be found in the implementation documentation.

2. Is it mandatory to make changes in the OEM codebase to implement this, or does it come with a new AOSP release by default? The platform-level change will come with a new AOSP release by default. Vendors may opt-in to this change in their codebase if they would like to apply it.

3. Are SoCs responsible for keeping the IOCTL list up to date? For example, if my device uses an ARM Mali GPU, would I need to reach out to ARM for any of the changes? Individual SoCs must update their IOCTL lists per device upon driver release. For example, ARM will update their published IOCTL list upon driver updates. However, OEMs should make sure that they incorporate the updates in their SEPolicy, and add any selected custom IOCTLs to the lists as needed.

4. Does this change apply to all Pixel in-market devices automatically, or is a user action required to toggle something to apply this change? This change applies to all Pixel in-market devices using the Mali GPU (Pixel 6-9). No user action is required to apply this change.

5. Will use of this policy impact the performance of the kernel driver? This policy was tested on the Mali GPU using GFXBench, and no measurable change to GPU performance was observed.

6. Is it necessary for the IOCTL list to align with the current userspace and kernel driver versions? Yes, the list of allowed IOCTLs must be synchronized with the IOCTLs supported by both the userspace and kernel drivers. If the IOCTLs in the user space or kernel driver are updated, the SEPolicy IOCTL list must be updated to match.

7. ARM has categorized IOCTLs as 'restricted' / 'instrumentation', but we want to use some of them in production use-cases, and/or deny others. Individual OEMs/SoCs are responsible for deciding on how to categorize the IOCTLs they use, based on the configuration of their userspace Mali libraries. ARM's list can be used to help decide on these, but each OEM/SoC's use-case may be different.

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 TBD 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

当面向 SDK 36 或更高版本的应用在搭载 Android 16 或更高版本的设备上提示用户授予照片和视频权限时，如果用户选择限制对所选媒体的访问权限，则会在照片选择器中看到该应用拥有的所有照片。用户可以取消选择任何这些预选项，这会撤消该应用对这些照片和视频的访问权限。