Perubahan perilaku: semua aplikasi

Platform Android 14 menyertakan perubahan perilaku yang mungkin memengaruhi aplikasi Anda. Perubahan perilaku berikut berlaku untuk semua aplikasi saat dijalankan di Android 14, terlepas dari targetSdkVersion. Sebaiknya uji aplikasi Anda lalu modifikasi sesuai kebutuhan untuk mendukung perubahan ini dengan tepat, jika memungkinkan.

Selain itu, pastikan Anda meninjau daftar perubahan perilaku yang hanya memengaruhi aplikasi yang menargetkan Android 14.

Fungsi inti

Menjadwalkan alarm yang tepat ditolak secara default

精确的闹钟适用于用户指定的通知,或是在确切时间需要执行的操作。从 Android 14 开始,系统不再向以 Android 13 及更高版本为目标平台的大多数新安装应用预先授予 SCHEDULE_EXACT_ALARM 权限,该权限默认处于拒绝状态。

详细了解安排精确闹钟的权限变化

Siaran yang terdaftar dalam konteks dimasukkan ke dalam antrean saat aplikasi di-cache

On Android 14, the system can place context-registered broadcasts in a queue while the app is in the cached state. This is similar to the queuing behavior that Android 12 (API level 31) introduced for async binder transactions. Manifest-declared broadcasts aren't queued, and apps are removed from the cached state for broadcast delivery.

When the app leaves the cached state, such as returning to the foreground, the system delivers any queued broadcasts. Multiple instances of certain broadcasts might be merged into one broadcast. Depending on other factors, such as system health, apps might be removed from the cached state, and any previously queued broadcasts are delivered.

Aplikasi hanya dapat menghentikan proses latar belakangnya sendiri

Starting in Android 14, when your app calls killBackgroundProcesses(), the API can kill only the background processes of your own app.

If you pass in the package name of another app, this method has no effect on that app's background processes, and the following message appears in Logcat:

Invalid packageName: com.example.anotherapp

Your app shouldn't use the killBackgroundProcesses() API or otherwise attempt to influence the process lifecycle of other apps, even on older OS versions. Android is designed to keep cached apps in the background and kill them automatically when the system needs memory. If your app kills other apps unnecessarily, it can reduce system performance and increase battery consumption by requiring full restarts of those apps later, which takes significantly more resources than resuming an existing cached app.

MTU ditetapkan ke 517 untuk klien GATT pertama yang meminta MTU

从 Android 14 开始,Android 蓝牙堆栈会更严格地遵循蓝牙核心规范 5.2 版,当第一个 GATT 客户端使用 BluetoothGatt#requestMtu(int) API 请求 MTU 时,会请求将 BLE ATT MTU 设置为 517 个字节,并忽略针对该 ACL 连接的所有后续 MTU 请求。

如需解决此变更并提高应用的稳健性,请考虑以下选项:

  • 您的外围设备应使用可由外围设备适应的合理值来响应 Android 设备的 MTU 请求。最终商定的值将为 Android 请求的值和远程提供的值(例如 min(517, remoteMtu))中的最小值
    • 实现此修复可能需要更新外围设备的固件
  • 或者,根据外围设备的已知受支持值与接收到的 MTU 变化之间的最小值限制 GATT 特征写入
    • 温馨提示:您应该在支持的标头大小的基础上减少 5 个字节
    • 例如:arrayMaxLength = min(SUPPORTED_MTU, GATT_MAX_ATTR_LEN(517)) - 5

Alasan baru aplikasi dapat ditempatkan di bucket standby terbatas

Android 14 introduces a new reason an app can be placed into the restricted standby bucket. The app's jobs trigger ANR errors multiple times due to onStartJob, onStopJob, or onBind method timeouts. (See JobScheduler reinforces callback and network behavior for changes to onStartJob and onStopJob.)

To track whether or not the app has entered the restricted standby bucket, we recommend logging with the API UsageStatsManager.getAppStandbyBucket() on job execution or UsageStatsManager.queryEventsForSelf() on app startup.

mlock dibatasi hingga 64 KB

在 Android 14(API 级别 34)及更高版本中,平台将可使用 mlock() 锁定的最大内存减少为每个进程 64 KB。在以前的版本中,每个进程的大小上限为 64 MB。此限制可促进跨应用和系统更好地管理内存。为了提高各设备之间的一致性,Android 14 针对兼容设备上的新 mlock() 限制添加了新的 CTS 测试

Sistem memberlakukan penggunaan resource aplikasi yang di-cache

By design, an app's process is in a cached state when it's moved to the background and no other app process components are running. Such an app process is subject to being killed due to system memory pressure. Any work that Activity instances perform after the onStop() method has been called and returned, while in this state, is unreliable and strongly discouraged.

Android 14 introduces consistency and enforcement to this design. Shortly after an app process enters a cached state, background work is disallowed, until a process component re-enters an active state of the lifecycle.

Apps that use typical framework-supported lifecycle APIs – such as services, JobScheduler, and Jetpack WorkManager – shouldn't be impacted by these changes.

Pengalaman pengguna

Perubahan pada cara pengguna menerima notifikasi yang tidak dapat ditutup

如果您的应用向用户显示不可关闭的前台通知,请注意:Android 14 已更改此行为,允许用户关闭此类通知。

这项变更适用于通过 Notification.Builder#setOngoing(true)NotificationCompat.Builder#setOngoing(true) 设置 Notification.FLAG_ONGOING_EVENT 来阻止用户关闭前台通知的应用。FLAG_ONGOING_EVENT 的行为已发生变化,使用户实际上能够关闭此类通知。

在以下情况下,此类通知仍不可关闭:

  • 当手机处于锁定状态时
  • 如果用户选择全部清除通知操作(有助于防止意外关闭)

此外,这种新行为不适用于以下用例中的通知:

  • CallStyle 通知
  • 企业设备政策控制器 (DPC) 和支持软件包
  • 媒体通知
  • 默认的搜索选择器软件包

Informasi keamanan data terlihat lebih jelas

为了加强用户隐私保护,Android 14 增加了系统显示您在 Play 管理中心表单中声明的信息的位置数量。目前,用户可以在 Google Play 中的应用详情的数据安全部分查看此信息。

我们建议您查看应用的位置数据分享政策,并花一点时间对应用的 Google Play“数据安全”部分进行任何适用的更新。

如需了解详情,请参阅有关如何在 Android 14 上以更显眼的方式显示数据安全信息的指南。

Aksesibilitas

Penskalaan font non-linear ke 200%

从 Android 14 开始,系统支持字体放大高达 200%,为弱视用户提供了符合网络内容无障碍指南 (WCAG) 的其他无障碍功能选项。

如果您已使用放大像素 (sp) 单位来定义文本大小,这项更改可能不会对您的应用产生太大影响。不过,您应在启用最大字号 (200%) 的情况下执行界面测试,确保应用能够在不影响易用性的情况下适应较大的字号。

Keamanan

API level target minimum yang dapat diinstal

从 Android 14 开始,targetSdkVersion 低于 23 的应用无法安装。要求应用满足这些最低目标 API 级别要求有助于提高用户的安全性和隐私性。

恶意软件通常会以较旧的 API 级别为目标平台,以绕过在较新版本 Android 中引入的安全和隐私保护机制。例如,有些恶意软件应用使用 targetSdkVersion 22,以避免受到 Android 6.0 Marshmallow(API 级别 23)在 2015 年引入的运行时权限模型的约束。这项 Android 14 变更使恶意软件更难以规避安全和隐私权方面的改进限制。尝试安装以较低 API 级别为目标平台的应用将导致安装失败,并且 Logcat 中会显示以下消息:

INSTALL_FAILED_DEPRECATED_SDK_VERSION: App package must target at least SDK version 23, but found 7

在升级到 Android 14 的设备上,targetSdkVersion 低于 23 的所有应用都将继续保持安装状态。

如果您需要测试以旧版 API 级别为目标平台的应用,请使用以下 ADB 命令:

adb install --bypass-low-target-sdk-block FILENAME.apk

Nama paket pemilik media mungkin akan disamarkan

The media store supports queries for the OWNER_PACKAGE_NAME column, which indicates the app that stored a particular media file. Starting in Android 14, this value is redacted unless at least one of the following conditions is true:

  • The app that stored the media file has a package name that is always visible to other apps.
  • The app that queries the media store requests the QUERY_ALL_PACKAGES permission.

Learn more about how Android filters package visibility for privacy purposes.