Giống như các bản phát hành trước, Android 14 có các thay đổi về hành vi có thể ảnh hưởng đến ứng dụng của bạn. Những thay đổi về hành vi sau đây chỉ áp dụng cho ứng dụng nhắm đến Android 14 (API cấp 34) trở lên. Nếu ứng dụng của bạn nhắm đến Android 14 trở lên, bạn nên điều chỉnh ứng dụng để hỗ trợ những hành vi này cho phù hợp (nếu cần).
Ngoài ra, hãy nhớ tham khảo danh sách các thay đổi về hành vi ảnh hưởng đến tất cả ứng dụng chạy trên Android 14 bất kể targetSdkVersion
của ứng dụng.
Chức năng cốt lõi
Bắt buộc phải có loại dịch vụ trên nền trước
如果您的应用以 Android 14(API 级别 34)或更高版本为目标平台,则必须为应用中的每个前台服务至少指定一项前台服务类型。您应选择一个能代表应用用例的前台服务类型。系统需要特定类型的前台服务满足特定用例。
如果应用中的用例与这些类型均不相关,强烈建议您迁移逻辑以使用 WorkManager 或用户发起的数据传输作业。
Thực thi quyền BLUETOOTH_CONNECT trong BluetoothAdapter
Android 14 enforces the BLUETOOTH_CONNECT
permission when calling the
BluetoothAdapter
getProfileConnectionState()
method for apps targeting
Android 14 (API level 34) or higher.
This method already required the BLUETOOTH_CONNECT
permission, but it was not
enforced. Make sure your app declares BLUETOOTH_CONNECT
in your app's
AndroidManifest.xml
file as shown in the following snippet and check that
a user has granted the permission before calling
getProfileConnectionState
.
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
Nội dung cập nhật OpenJDK 17
Android 14 continues the work of refreshing Android's core libraries to align with the features in the latest OpenJDK LTS releases, including both library updates and Java 17 language support for app and platform developers.
A few of these changes can affect app compatibility:
- Changes to regular expressions: Invalid group references are now
disallowed to more closely follow the semantics of OpenJDK. You might see
new cases where an
IllegalArgumentException
is thrown by thejava.util.regex.Matcher
class, so make sure to test your app for areas that use regular expressions. To enable or disable this change while testing, toggle theDISALLOW_INVALID_GROUP_REFERENCE
flag using the compatibility framework tools. - UUID handling: The
java.util.UUID.fromString()
method now does more strict checks when validating the input argument, so you might see anIllegalArgumentException
during deserialization. To enable or disable this change while testing, toggle theENABLE_STRICT_VALIDATION
flag using the compatibility framework tools. - ProGuard issues: In some cases, the addition of the
java.lang.ClassValue
class causes an issue if you try to shrink, obfuscate, and optimize your app using ProGuard. The problem originates with a Kotlin library that changes runtime behaviour based on whetherClass.forName("java.lang.ClassValue")
returns a class or not. If your app was developed against an older version of the runtime without thejava.lang.ClassValue
class available, then these optimizations might remove thecomputeValue
method from classes derived fromjava.lang.ClassValue
.
JobScheduler củng cố hành vi gọi lại và hành vi mạng
Since its introduction, JobScheduler expects your app to return from
onStartJob
or onStopJob
within a few seconds. Prior to Android 14,
if a job runs too long, the job is stopped and fails silently.
If your app targets Android 14 (API level 34) or higher and
exceeds the granted time on the main thread, the app triggers an ANR
with the error message "No response to onStartJob
" or
"No response to onStopJob
".
This ANR may be a result of 2 scenarios:
1. There is work blocking the main thread, preventing the callbacks onStartJob
or onStopJob
from executing and completing within the expected time limit.
2. The developer is running blocking work within the JobScheduler
callback onStartJob
or onStopJob
, preventing the callback from
completing within the expected time limit.
To address #1, you will need to further debug what is blocking the main thread
when the ANR occurs, you can do this using
ApplicationExitInfo#getTraceInputStream()
to get the tombstone
trace when the ANR occurs. If you're able to manually reproduce the ANR,
you can record a system trace and inspect the trace using either
Android Studio or Perfetto to better understand what is running on
the main thread when the ANR occurs.
Note that this can happen when using JobScheduler API directly
or using the androidx library WorkManager.
To address #2, consider migrating to WorkManager, which provides
support for wrapping any processing in onStartJob
or onStopJob
in an asynchronous thread.
JobScheduler
also introduces a requirement to declare the
ACCESS_NETWORK_STATE
permission if using setRequiredNetworkType
or
setRequiredNetwork
constraint. If your app does not declare the
ACCESS_NETWORK_STATE
permission when scheduling the job and is targeting
Android 14 or higher, it will result in a SecurityException
.
Tiles launch API
对于以 Android 14 及更高版本为目标平台的应用,
TileService#startActivityAndCollapse(Intent)
已弃用,现在会抛出
调用时抛出异常。如果您的应用从功能块启动 activity,请使用
TileService#startActivityAndCollapse(PendingIntent)
。
Quyền riêng tư
Quyền truy cập một phần vào ảnh và video
Android 14 引入了“已选照片访问权限”,让用户可以向应用授予对其媒体库中特定图片和视频的访问权限,而不是授予对给定类型的所有媒体的访问权限。
只有当您的应用以 Android 14(API 级别 34)或更高版本为目标平台时,此更改才会启用。如果您尚未使用照片选择器,我们建议您在应用中实现照片选择器,以提供一致的图片和视频选择体验,同时增强用户隐私保护,而无需请求任何存储权限。
如果您使用存储权限维护自己的图库选择器,并且需要对实现保持完全控制,请调整实现以使用新的 READ_MEDIA_VISUAL_USER_SELECTED
权限。如果您的应用不使用新权限,系统会以兼容模式运行您的应用。
Trải nghiệm người dùng
Thông báo bảo mật về ý định toàn màn hình
With Android 11 (API level 30), it was possible for any app to use
Notification.Builder.setFullScreenIntent
to send full-screen
intents while the phone is locked. You could auto-grant this on app install by
declaring USE_FULL_SCREEN_INTENT
permission in the
AndroidManifest.
Full-screen intent notifications are designed for extremely high-priority
notifications demanding the user's immediate attention, such as an incoming
phone call or alarm clock settings configured by the user. For apps targeting
Android 14 (API level 34) or higher, apps that are allowed to use this
permission are limited to those that provide calling and alarms only. The Google
Play Store revokes default USE_FULL_SCREEN_INTENT
permissions for any apps
that don't fit this profile. The deadline for these policy changes is May 31,
2024.
This permission remains enabled for apps installed on the phone before the user updates to Android 14. Users can turn this permission on and off.
You can use the new API
NotificationManager.canUseFullScreenIntent
to check if your app
has the permission; if not, your app can use the new intent
ACTION_MANAGE_APP_USE_FULL_SCREEN_INTENT
to launch the settings
page where users can grant the permission.
Bảo mật
Các quy tắc hạn chế đối với ý định ngầm ẩn và ý định đang chờ xử lý
对于以 Android 14(API 级别 34)或更高版本为目标平台的应用,Android 会通过以下方式限制应用向内部应用组件发送隐式 intent:
- 隐式 intent 只能传送到导出的组件。应用必须使用显式 intent 传送到未导出的组件,或将该组件标记为已导出。
- 如果应用通过未指定组件或软件包的 intent 创建可变待处理 intent,系统会抛出异常。
这些变更可防止恶意应用拦截意在供应用内部组件使用的隐式 intent。
例如,下面是可以在应用的清单文件中声明的 intent 过滤器:
<activity
android:name=".AppActivity"
android:exported="false">
<intent-filter>
<action android:name="com.example.action.APP_ACTION" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
如果应用尝试使用隐式 intent 启动此 activity,则系统会抛出 ActivityNotFoundException
异常:
Kotlin
// Throws an ActivityNotFoundException exception when targeting Android 14. context.startActivity(Intent("com.example.action.APP_ACTION"))
Java
// Throws an ActivityNotFoundException exception when targeting Android 14. context.startActivity(new Intent("com.example.action.APP_ACTION"));
如需启动非导出的 activity,应用应改用显式 intent:
Kotlin
// This makes the intent explicit. val explicitIntent = Intent("com.example.action.APP_ACTION") explicitIntent.apply { package = context.packageName } context.startActivity(explicitIntent)
Java
// This makes the intent explicit. Intent explicitIntent = new Intent("com.example.action.APP_ACTION") explicitIntent.setPackage(context.getPackageName()); context.startActivity(explicitIntent);
Broadcast receiver đã đăng ký trong thời gian chạy phải chỉ định hành vi xuất
以 Android 14(API 级别 34)或更高版本为目标平台并使用上下文注册的接收器的应用和服务必须指定以下标志,以指明接收器是否应导出到设备上的所有其他应用:RECEIVER_EXPORTED
或 RECEIVER_NOT_EXPORTED
。此要求有助于利用 Android 13 中引入的这些接收器的功能,来保护应用免受安全漏洞的影响。
仅接收系统广播的接收器的例外情况
如果您的应用仅通过 Context#registerReceiver
方法(例如 Context#registerReceiver()
)针对系统广播注册接收器,那么它在注册接收器时不应指定标志。
Tải mã động an toàn hơn
如果您的应用以 Android 14(API 级别 34)或更高版本为目标平台并使用动态代码 正在加载 (DCL),所有动态加载的文件都必须标记为只读。 否则,系统会抛出异常。我们建议应用尽可能避免动态加载代码,因为这样做会大大增加应用因代码注入或代码篡改而遭到入侵的风险。
如果必须动态加载代码,请使用以下方法,在动态文件(例如 DEX、JAR 或 APK 文件)打开并写入任何内容之前立即将其设为只读:
Kotlin
val jar = File("DYNAMICALLY_LOADED_FILE.jar") val os = FileOutputStream(jar) os.use { // Set the file to read-only first to prevent race conditions jar.setReadOnly() // Then write the actual file content } val cl = PathClassLoader(jar, parentClassLoader)
Java
File jar = new File("DYNAMICALLY_LOADED_FILE.jar"); try (FileOutputStream os = new FileOutputStream(jar)) { // Set the file to read-only first to prevent race conditions jar.setReadOnly(); // Then write the actual file content } catch (IOException e) { ... } PathClassLoader cl = new PathClassLoader(jar, parentClassLoader);
处理已存在的动态加载文件
为防止系统对现有动态加载的文件抛出异常,我们建议您先删除并重新创建文件,然后再尝试在应用中重新动态加载这些文件。重新创建文件时,请按照上述指南在写入时将文件标记为只读。或者,您可以将现有文件重新标记为只读,但在这种情况下,我们强烈建议您先验证文件的完整性(例如,对照可信值检查文件的签名)以保护应用免遭恶意操作的影响。
Hạn chế bổ sung khi bắt đầu hoạt động ở chế độ nền
For apps targeting Android 14 (API level 34) or higher, the system further restricts when apps are allowed to start activities from the background:
- When an app sends a
PendingIntent
usingPendingIntent#send()
or similar methods, the app must opt in if it wants to grant its own background activity launch privileges to start the pending intent. To opt in, the app should pass anActivityOptions
bundle withsetPendingIntentBackgroundActivityStartMode(MODE_BACKGROUND_ACTIVITY_START_ALLOWED)
. - When a visible app binds a service of another app that's in the background
using the
bindService()
method, the visible app must now opt in if it wants to grant its own background activity launch privileges to the bound service. To opt in, the app should include theBIND_ALLOW_ACTIVITY_STARTS
flag when calling thebindService()
method.
These changes expand the existing set of restrictions to protect users by preventing malicious apps from abusing APIs to start disruptive activities from the background.
Truyền tải qua đường dẫn Zip
对于以 Android 14(API 级别 34)或更高版本为目标平台的应用,Android 会通过以下方式防止 Zip 路径遍历漏洞:如果 Zip 文件条目名称包含“..”或以“/”开头,ZipFile(String)
和 ZipInputStream.getNextEntry()
会抛出 ZipException
。
应用可以通过调用 dalvik.system.ZipPathValidator.clearCallback()
选择停用此验证。
Bắt buộc phải có sự đồng ý của người dùng cho mỗi phiên chụp MediaProjection
对于以 Android 14(API 级别 34)或更高版本为目标平台的应用,在以下任一情况下,MediaProjection#createVirtualDisplay
都会抛出 SecurityException
:
- 您的应用会缓存从
MediaProjectionManager#createScreenCaptureIntent
返回的Intent
,并多次将其传递给MediaProjectionManager#getMediaProjection
。 - 您的应用在同一
MediaProjection
实例上多次调用MediaProjection#createVirtualDisplay
。
您的应用必须在每次捕获会话之前征求用户同意。单次捕获会话是对 MediaProjection#createVirtualDisplay
的单次调用,并且每个 MediaProjection
实例只能使用一次。
处理配置变更
如果您的应用需要调用 MediaProjection#createVirtualDisplay
来处理配置更改(例如屏幕方向或屏幕大小更改),您可以按照以下步骤更新现有 MediaProjection
实例的 VirtualDisplay
:
- 使用新的宽度和高度调用
VirtualDisplay#resize
。 - 向
VirtualDisplay#setSurface
提供新的Surface
,并为其指定新的宽度和高度。
注册回调
您的应用应注册回调,以处理用户不同意继续拍摄会话的情况。为此,请实现 Callback#onStop
,并让应用释放所有相关资源(例如 VirtualDisplay
和 Surface
)。
如果您的应用未注册此回调,当您的应用调用它时,MediaProjection#createVirtualDisplay
会抛出 IllegalStateException
。
Các quy tắc hạn chế mới cập nhật đối với yếu tố ngoài SDK
Android 14 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 14 为目标平台,其中一些变更可能不会立即对您产生影响。然而,虽然您目前仍可以使用一些非 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,则可以测试您的应用来进行确认。如果您的应用依赖于非 SDK 接口,您应该开始计划迁移到 SDK 替代方案。然而,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,应请求新的公共 API。
如需详细了解此 Android 版本中的变更,请参阅 Android 14 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。