Mudanças de comportamento: todos os apps

A plataforma Android 14 inclui mudanças de comportamento que podem afetar seu app. As mudanças de comportamento a seguir se aplicam a todos os apps executados no Android 14, independente da targetSdkVersion. Teste seu app e modifique-o conforme necessário para ficar compatível com essas mudanças, quando aplicável.

Consulte também a lista de mudanças de comportamento que afetam apenas os apps destinados ao Android 14.

Principal recurso

Programar alarmes exatos não é permitido por padrão

Exact alarms are meant for user-intentioned notifications, or for actions that need to happen at a precise time. Starting in Android 14, the SCHEDULE_EXACT_ALARM permission is no longer being pre-granted to most newly installed apps targeting Android 13 and higher—the permission is denied by default.

Learn more about the changes to the permission for scheduling exact alarms.

As transmissões registradas em contexto são enfileiradas enquanto os apps são armazenados em 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.

Os apps só podem encerrar os próprios processos em segundo plano

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.

A MTU está definida como 517 para o primeiro cliente GATT que solicita uma 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,并在第一个 GATT 客户端使用 BluetoothGatt#requestMtu(int) API 请求 MTU 时将 BLE ATT MTU 请求设为 517 字节,并忽略该 ACL 连接上的所有后续 MTU 请求。

如需解决此更改并使您的应用更为稳健,请考虑以下选项:

  • 您的外围设备应使用外围设备可以容纳的合理值来响应 Android 设备的 MTU 请求。最终协商的值将是 Android 请求的值和远程提供的值(例如 min(517, remoteMtu))的较小值
    • 实现此修复程序可能需要更新外围设备的固件
  • 或者,您也可以根据外围设备的已知支持值与收到的 MTU 更改值之间的最小值来限制 GATT 特征写入
    • 提醒您,应将标头的支持大小减小 5 个字节
    • 例如:arrayMaxLength = min(SUPPORTED_MTU, GATT_MAX_ATTR_LEN(517)) - 5

Novo motivo para um app ser colocado no bucket de espera restrito

O Android 14 apresenta um novo motivo para um app ser colocado no bucket de espera restrito. Os jobs do app acionam erros de ANR várias vezes devido a tempos limite de método onStartJob, onStopJob ou onBind. Consulte O JobScheduler reforça o callback e o comportamento de rede para ver as mudanças em onStartJob e onStopJob.

Para acompanhar se o app entrou ou não no bucket de espera restrito, recomendamos fazer o registro com a API UsageStatsManager.getAppStandbyBucket() na execução do job ou UsageStatsManager.queryEventsForSelf() na inicialização do app.

mlock limitado a 64 KB

In Android 14 (API level 34) and higher, the platform reduces the maximum memory that can be locked using mlock() to 64 KB per process. In previous versions, the limit was 64 MB per process. This restriction promotes better memory management across apps and the system. To provide more consistency across devices, Android 14 adds a new CTS test for the new mlock() limit on compatible devices.

O sistema impõe o uso de recursos de apps em 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.

Experiência do usuário

Mudanças na experiência dos usuários com notificações não dispensáveis

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。

这项变更适用于阻止用户关闭前台的应用 将 Notification.FLAG_ONGOING_EVENT 设置为 Notification.Builder#setOngoing(true)NotificationCompat.Builder#setOngoing(true)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,这一新行为不适用于以下用例中的通知:

  • CallStyle 条通知
  • 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

As informações de segurança dos dados estão mais visíveis

To enhance user privacy, Android 14 increases the number of places where the system shows the information you have declared in the Play Console form. Currently, users can view this information in the Data safety section on your app's listing in Google Play.

We encourage you to review your app's location data sharing policies and take a moment to make any applicable updates to your app's Google Play Data safety section.

Learn more in the guide about how data safety information is more visible on Android 14.

Acessibilidade

Dimensionamento de fonte não linear para 200%

No Android 14 e mais recentes, o sistema oferece suporte ao dimensionamento de fontes de até 200%, dando aos usuários com baixa visão outras opções de acessibilidade alinhadas às Diretrizes de Acessibilidade para Conteúdo Web (WCAG, na sigla em inglês).

Se você já usa unidades de pixels dimensionados (sp) para definir o tamanho do texto, essa mudança provavelmente não terá um impacto alto no seu app. No entanto, faça testes de interface com o tamanho máximo de fonte ativado (200%) para garantir que o app possa acomodar tamanhos de fonte maiores sem afetar a usabilidade.

Segurança

Nível mínimo desejado para a instalação da API

Starting with Android 14, apps with a targetSdkVersion lower than 23 can't be installed. Requiring apps to meet these minimum target API level requirements improves security and privacy for users.

Malware often targets older API levels in order to bypass security and privacy protections that have been introduced in newer Android versions. For example, some malware apps use a targetSdkVersion of 22 to avoid being subjected to the runtime permission model introduced in 2015 by Android 6.0 Marshmallow (API level 23). This Android 14 change makes it harder for malware to avoid security and privacy improvements. Attempting to install an app targeting a lower API level will result in an installation failure, with the following message appearing in Logcat:

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

On devices upgrading to Android 14, any apps with a targetSdkVersion lower than 23 will remain installed.

If you need to test an app targeting an older API level, use the following ADB command:

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

Os nomes dos pacotes de proprietários de mídia podem ser editados

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.