行为变更：所有应用

Android 17 平台包含一些可能会影响您的应用的行为变更。以下行为变更将影响在 Android 17 上运行的所有应用，无论采用哪种 targetSdkVersion 都不例外。您应该测试您的应用，然后根据需要酌情修改，以便支持这些变更。

此外，请务必查看仅影响以 Android 17 为目标平台的应用的行为变更列表。

注意： 本页列出了一些比较重要的变更。如需了解更多详细信息，请参阅 Android 17 版本说明。

核心功能

Android 17（API 级别 37）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。

应用内存限制

Android 17 introduces app memory limits based on the device's total RAM to create a more stable and deterministic environment for your applications and Android users. In Android 17, limits are set conservatively to establish system baselines, targeting extreme memory leaks and other outliers before they trigger system-wide instability resulting in UI stuttering, higher battery drain, and apps being killed. While we anticipate minimal impact on the vast majority of app sessions, we recommend the following memory best practices, including establishing a baseline for memory.

Note: Memory limits are only imposed on a subset of Android devices.

You can determine if your app session was impacted by calling getDescription in ApplicationExitInfo; if your app was affected, the exit reason will be REASON_OTHER and the description will contain the string "MemoryLimiter:AnonSwap" along with other information. You can also use trigger-based profiling with TRIGGER_TYPE_ANOMALY to get heap dumps that are collected when the memory limit is hit.

The Manage your app's memory documentation gives information to help you diagnose your app's memory issues and optimize its resource consumption.

Test your app's behavior under the memory constraints

You can use Android Debug Bridge (adb) to adjust or disable the memory limits on any device that imposes them. The shell command am provides three subcommands to adjust the memory limits. (These commands have no effect on a device which does not impose memory limits.)

• am memory-limiter ignore <uid>|none|all
• am memory-limiter manual <pid> <limit>|max|none
• am memory-limiter status

ignore

Instructs the memory limiter to ignore some or all processes. Passing a UID instructs the memory limiter to ignore all processes associated with that UID. You can also pass all (ignore all processes) or none (do not ignore any processes). Passing none overrides any previous calls to am memory-limiter ignore.

If you instruct the memory limiter to ignore a process, you can still apply a manual memory limit to the process by calling am memory-limiter manual.

manual

Instructs the system to impose a memory constraint on the process with the specified PID. The memory constraint is specified as an integer number of MB; for example, passing 30 specifies that the process is limited to 30 MB of memory. Passing max removes all memory limits on that process. Passing none removes any manual limits set on the process, restoring the system's default limit (if any).

status

Reports the current status of the memory limiter. The status includes the memory limits imposed on visible and non-visible processes.

隐私权

Android 17 包含以下变更，旨在提升用户隐私保护。

动态短信密码保护

Beginning with Android 17, Android is expanding its protection for SMS messages containing one-time passwords (OTP).

In previous versions of Android, this protection was primarily focused on the SMS Retriever format. Delivery of messages containing an SMS retriever hash was delayed for most apps for three hours. However, certain certain apps (like the default SMS handler) were exempt from the delay, and the app that owned the hash was also exempted.

Beginning with Android 17, the protection is also applied to WebOTP format messages. If an app has permission to read SMS messages but is not the intended recipient of a WebOTP message (as determined by domain verification), the message is not accessible to the app until three hours after the message's receipt. This change is intended to improve user security by ensuring that only apps associated with the domain mentioned in the message can programmatically read the verification code.

During this three hour delay, the SMS_RECEIVED_ACTION broadcast is withheld and SMS provider database queries are filtered. The SMS message is available to these apps after the delay. This change applies to all apps, regardless of their target API level.

Certain apps such as the default SMS assistant app, connected device companion apps, etc., are exempted from this delay. All apps that rely on reading SMS messages for OTP extraction should transition to using SMS Retriever or SMS User Consent APIs to ensure continued functionality.

Note: If your app targets Android 17 (API level 37) or higher, this protection is also extended to standard SMS messages. For more information, see OTP protection for standard SMS messages in the Behavior changes: Apps targeting Android 17 documentation.

安全

Android 17 包含以下设备和应用安全方面的改进。

usesClearTraffic 弃用计划

In a future release, we plan to deprecate the usesCleartextTraffic element. Apps that need to make unencrypted (HTTP) connections should migrate to using a network security configuration file, which lets you specify which domains your app needs to make cleartext connections to.

Be aware that network security configuration files are only supported on API levels 24 and higher. If your app has a minimum API level lower than 24, you should do both of the following:

• Set the usesCleartextTraffic attribute to true
• Use a network configuration file

If your app's minimum API level is 24 or higher, you can use a network configuration file and you don't need to set usesCleartextTraffic.

限制隐式 URI 授权

Currently, if an app launches an intent with a URI that has the action ACTION_SEND, ACTION_SEND_MULTIPLE, or ACTION_IMAGE_CAPTURE, the system automatically grants the read and write URI permissions to the target app. Starting in Android 18, the system will no longer automatically grant these permissions. For this reason, we recommend that apps explicitly grant the relevant URI permissions instead of relying on the system to grant them.

To detect the usage of these intents in your app, use StrictMode with detectImplicitUriPermissionGrant() to trigger a violation:

Kotlin

val policy = StrictMode.VmPolicy.Builder()
    .detectImplicitUriPermissionGrant()
    .penaltyLog()
    .build()
StrictMode.setVmPolicy(policy)

Java

StrictMode.VmPolicy policy = new StrictMode.VmPolicy.Builder()
    .detectImplicitUriPermissionGrant()
    .penaltyLog()
    .build();
StrictMode.setVmPolicy(policy);

Alternatively, you can monitor for logged exceptions containing the message Please set the grant explicitly in the app that appears when system implicitly sets the grant. You can monitor for these logs using the following adb command:

adb logcat | grep "Please set the grant explicitly in the app"

To explicitly grant the necessary permissions, add the FLAG_GRANT_READ_URI_PERMISSION flag to ACTION_SEND and ACTION_SEND_MULTIPLE intents:

Kotlin

intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION)

Java

intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);

Include both FLAG_GRANT_READ_URI_PERMISSION and FLAG_GRANT_WRITE_URI_PERMISSION flags for ACTION_IMAGE_CAPTURE intents:

Kotlin

intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION or Intent.FLAG_GRANT_WRITE_URI_PERMISSION)

Java

intent.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION | Intent.FLAG_GRANT_WRITE_URI_PERMISSION);

每个应用的密钥库限制

Apps should avoid creating excessive numbers of keys in Android Keystore, because it is a shared resource for all apps on the device. Beginning with Android 17, the system enforces a limit on the number of keys an app can own. The limit is 50,000 keys for non-system apps targeting Android 17 (API level 37) or higher, and 200,000 keys for all other apps. System apps have a limit of 200,000 keys, regardless of which API level they target.

If an app attempts to create keys beyond the limit, the creation fails with a KeyStoreException. The exception's message string contains information about the key limit. If the app calls getNumericErrorCode() on the exception, the return value depends on what API level the app targets:

• Apps targeting Android 17 (API level 37) or higher: getNumericErrorCode() returns the new ERROR_TOO_MANY_KEYS value.
• All other apps: getNumericErrorCode() returns ERROR_INCORRECT_USAGE.

阻止跨资料环回流量

从 Android 17 开始，默认情况下不再允许跨个人资料环回流量。同一个人资料内的环回流量不受影响。 此项变更适用于在 Android 17 或更高版本上运行的所有应用，无论应用以哪个 API 级别为目标平台。

用户体验和系统界面

Android 17 包含以下变更，旨在打造更一致、更直观的用户体验。

在旋转后恢复默认 IME 可见性

Beginning with Android 17, when the device's configuration changes (for example, through rotation), and this is not handled by the app itself, the previous IME visibility is not restored.

If your app undergoes a configuration change that it does not handle, and the app needs the keyboard to be visible after the change, you must explicitly request this. You can make this request in one of the following ways:

• Set the android:windowSoftInputMode attribute to stateAlwaysVisible.
• Programmatically request the soft keyboard in your activity's onCreate() method, or add the onConfigurationChanged() method.

人工输入

Android 17 包含以下变更，这些变更会影响应用与键盘和触控板等人工输入设备的互动方式。

在指针捕获期间，触控板默认传递相对事件

从 Android 17 开始，如果应用使用 View.requestPointerCapture() 请求捕获指针，并且用户使用触控板，系统会识别用户触摸操作产生的指针移动和滚动手势，并以与捕获的鼠标产生的指针和滚轮移动相同的方式将这些信息报告给应用。在大多数情况下，这使得支持捕获鼠标的应用无需为触控板添加特殊的处理逻辑。如需了解详情，请参阅 View.POINTER_CAPTURE_MODE_RELATIVE 的文档。

之前，系统不会尝试识别触控板的手势，而是以类似于触摸屏触摸的格式将原始的绝对手指位置传递给应用。如果应用仍需要此绝对数据，则应改为使用 View.POINTER_CAPTURE_MODE_ABSOLUTE 调用新的 View.requestPointerCapture(int) 方法。

媒体

Android 17 针对媒体行为做了以下更改。

后台音频安全加固

Beginning with Android 17, the audio framework enforces restrictions on background audio interactions including audio playback, audio focus requests, and volume change APIs to ensure that these changes are started intentionally by the user.

If the app tries to call audio APIs while the app is not in a valid lifecycle, the audio playback and volume change APIs fail silently without throwing an exception or providing a failure message. The audio focus API fails with the result code AUDIOFOCUS_REQUEST_FAILED.

Note: The restrictions are more stringent if an app targets Android 17 (API level 37). For these apps, the foreground service must have while-in-use (WIU) capabilities, unless the app has the exact alarm permission and is interacting with USAGE_ALARM audio streams.

For more information, including mitigation strategies, see Background audio hardening.

连接

Android 17 包含以下变更，以增强设备连接性。

针对蓝牙绑定丢失的自主重新配对

Android 17 introduces autonomous re-pairing, a system-level enhancement designed to automatically resolve Bluetooth bond loss.

Previously, if a bond was lost, users had to manually navigate to Settings to unpair and then re-pair the peripheral. This feature builds upon the security improvement of Android 16 by allowing the system to re-establish bonds in the background without requiring users to manually navigate to Settings to unpair and re-pair peripherals.

While most apps will not require code changes, developers should be aware of the following behavior changes in Bluetooth stack:

• New pairing context: The ACTION_PAIRING_REQUEST now includes the EXTRA_PAIRING_CONTEXT extra which allows apps to distinguish between a standard pairing request and an autonomous system-initiated re-pairing attempt.
• Conditional key updates: Existing security keys will only be replaced if the re-pairing is successful and new connection meets or exceeds the security level of the previous bond.
• Modified intent timing: The ACTION_KEY_MISSING intent is now broadcast only if the autonomous re-pairing attempt fails. This reduces unnecessary error handling in the app if the system successfully recovers the bond in the background.
• User notification: The system manages re-pairing via new UI notifications and dialogs. Users will be prompted to confirm the re-pairing attempt to ensure they are aware of the reconnection.

Peripheral device manufacturers and companion app developers should verify that hardware and app gracefully handle bond transitions. To test this behavior, simulate a remote bond loss using either of the following methods:

• Manually remove the bond information from the peripheral device
• Manually unpair the device in: Settings > Connected devices