与以前的版本一样,Android 15 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 15 或更高版本为目标平台的应用。如果您的应用以 Android 15 或更高版本为目标平台,您应该修改自己的应用以适当地支持这些行为(如果适用)。
此外,请务必查看对 Android 15 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)。
核心功能
Android 15 修改或扩展了 Android 系统的各种核心功能。
前台服务的变更
我们将对 Android 15 中的前台服务做出以下更改。
数据同步前台服务超时行为
Android 15 对于以 Android 15 或更高版本为目标平台的应用,在 dataSync
中引入了新的超时行为。此行为也适用于新的 mediaProcessing
前台服务类型。
系统允许应用的 dataSync
服务在 24 小时内运行总共 6 小时,之后系统会调用正在运行的服务的 Service.onTimeout(int, int)
方法(在 Android 15 中引入)。此时,服务只有几秒钟的时间来调用 Service.stopSelf()
。当调用 Service.onTimeout()
时,该服务不再被视为前台服务。如果服务未调用 Service.stopSelf()
,则会发生故障,并显示以下错误消息:“A for 前台服务 (<fgs_type> does not stop in their timeout:
<component_name>)”。在 Beta 版 2 中,失败消息显示为 ANR,但在未来的 Beta 版中,此失败消息将抛出自定义异常。
为避免此行为变更出现问题,您可以执行以下一项或多项操作:
- 让您的服务实现新的
Service.onTimeout(int, int)
方法。当应用收到回调时,请确保在几秒钟内调用stopSelf()
。(如果您没有立即停止应用,系统会生成故障。) - 确保应用的
dataSync
服务在任何 24 小时内的运行时间总共不超过 6 小时(除非用户与应用互动,请重置计时器)。 - 仅因直接用户互动而启动
dataSync
前台服务;由于您的应用在服务启动时正处于前台,因此在它进入后台后,您的服务有整整六个小时的时间。 - 请使用替代 API,而不要使用
dataSync
前台服务。
如果应用的 dataSync
前台服务在过去 24 小时内运行了 6 小时,那么除非用户已将您的应用带到前台(这会重置计时器),否则您无法启动其他 dataSync
前台服务。如果您尝试启动另一个 dataSync
前台服务,系统会抛出 ForegroundServiceStartNotAllowedException
,并显示“时间限制已用完前台服务类型 dataSync 的时间限制”这样的错误消息。
新增媒体处理前台服务类型
Android 15 introduces a new foreground service type, mediaProcessing
. This
service type is appropriate for operations like transcoding media files. For
example, a media app might download an audio file and need to convert it to a
different format before playing it. You can use a mediaProcessing
foreground
service to make sure the conversion continues even while the app is in the
background.
The system permits an app's mediaProcessing
services to run for a total of 6
hours in a 24-hour period, after which the system calls the running service's
Service.onTimeout(int, int)
method (introduced in Android
15). At this time, the service has a few seconds to call
Service.stopSelf()
. If the service does not
call Service.stopSelf()
, the system throws an internal exception. The
exception is logged in Logcat with the following message:
Fatal Exception: android.app.RemoteServiceException: "A foreground service of
type mediaProcessing did not stop within its timeout: [component name]"
To avoid having the exception, you can do one of the following:
- Have your service implement the new
Service.onTimeout(int, int)
method. When your app receives the callback, make sure to callstopSelf()
within a few seconds. (If you don't stop the app right away, the system generates a failure.) - Make sure your app's
mediaProcessing
services don't run for more than a total of 6 hours in any 24-hour period (unless the user interacts with the app, resetting the timer). - Only start
mediaProcessing
foreground services as a result of direct user interaction; since your app is in the foreground when the service starts, your service has the full six hours after the app goes to the background. - Instead of using a
mediaProcessing
foreground service, use an alternative API, like WorkManager.
If your app's mediaProcessing
foreground services have run for 6 hours in the
last 24, you cannot start another mediaProcessing
foreground service unless
the user has brought your app to the foreground (which resets the timer). If you
try to start another mediaProcessing
foreground service, the system throws
ForegroundServiceStartNotAllowedException
with an error message like "Time limit already exhausted for foreground service
type mediaProcessing".
For more information about the mediaProcessing
service type, see Changes to
foreground service types for Android 15: Media processing.
Testing
To test your app's behavior, you can enable media processing timeouts even if
your app is not targeting Android 15 (as long as the app is running on an
Android 15 device). To enable timeouts, run the following adb
command:
adb shell am compat enable FGS_INTRODUCE_TIME_LIMITS your-package-name
You can also adjust the timeout period, to make it easier to test how your
app behaves when the limit is reached. To set a new timeout period, run the
following adb
command:
adb shell device_config put activity_manager data_sync_fgs_timeout_duration duration-in-milliseconds
对启动前台服务的 BOOT_COMPLETED
广播接收器的限制
There are new restrictions on BOOT_COMPLETED
broadcast receivers launching
foreground services. BOOT_COMPLETED
receivers are not allowed to launch the
following types of foreground services:
dataSync
camera
mediaPlayback
phoneCall
mediaProjection
microphone
(this restriction has been in place formicrophone
since Android 14)
If a BOOT_COMPLETED
receiver tries to launch any of those types of foreground
services, the system throws ForegroundServiceStartNotAllowedException
.
限制在应用拥有 SYSTEM_ALERT_WINDOW
权限的情况下启动前台服务
以前,如果应用拥有 SYSTEM_ALERT_WINDOW
权限,那么即使该应用当前在后台运行,它也可以启动前台服务(如不受后台启动限制的豁免中所述)。
如果应用以 Android 15 为目标平台,此豁免范围现在会更严格。该应用现在需要具有 SYSTEM_ALERT_WINDOW
权限,并且还具有可见的叠加窗口。也就是说,在您启动前台服务之前,应用需要先启动 TYPE_APPLICATION_OVERLAY
窗口,并且该窗口必须处于可见状态。
如果您的应用尝试在不满足这些新要求的情况下从后台启动前台服务(并且没有其他某些豁免),系统会抛出 ForegroundServiceStartNotAllowedException
。
如果您的应用声明 SYSTEM_ALERT_WINDOW
权限并从后台启动前台服务,则可能会受到此项变更的影响。如果您的应用收到 ForegroundServiceStartNotAllowedException
,请检查应用的操作顺序,并确保应用在尝试从后台启动前台服务之前已具备有效的叠加窗口。您可以通过调用 View.getWindowVisibility()
检查叠加层窗口当前是否可见,也可以替换 View.onWindowVisibilityChanged()
,以便在可见性发生变化时收到通知。
更改了应用何时可以修改勿扰模式的全局状态
Apps that target Android 15 can no longer change the global state or policy of
Do Not Disturb (DND) on a device (either by modifying user settings, or turning
off DND mode). Instead, apps must contribute an AutomaticZenRule
, which
the system combines into a global policy with the existing
most-restrictive-policy-wins scheme. Calls to existing APIs that previously
affected global state (setInterruptionFilter
,
setNotificationPolicy
) result in the creation or update of an
implicit AutomaticZenRule
, which is toggled on and off depending on the
call-cycle of those API calls.
Note that this change only affects observable behavior if the app is calling
setInterruptionFilter(INTERRUPTION_FILTER_ALL)
and expects that call to
deactivate an AutomaticZenRule
that was previously activated by their owners.
OpenJDK 17 变更
Android 15 会继续更新 Android 的核心库,以与最新 OpenJDK LTS 版本中的功能保持一致。
对于以 Android 15 为目标平台的应用,以下变更可能会影响应用兼容性:
字符串格式设置 API 的变化:在使用以下
String.format()
和Formatter.format()
API 时,现在对参数索引、标志、宽度和精度的验证更为严格:String.format(String, Object[])
String.format(Locale, String, Object[])
Formatter.format(String, Object[])
Formatter.format(Locale, String, Object[])
例如,使用参数索引 0 时(格式字符串中的
%0
)会抛出以下异常:IllegalFormatArgumentIndexException: Illegal format argument index = 0
在这种情况下,可以通过在格式字符串中使用
%1
的参数索引 1 来解决此问题。对
Arrays.asList(...).toArray()
组件类型的更改:使用Arrays.asList(...).toArray()
时,所生成数组的组件类型现在是Object
,而不是底层数组元素的类型。因此,以下代码会抛出ClassCastException
:String[] elements = (String[]) Arrays.asList("one", "two").toArray();
在这种情况下,若要在结果数组中保留
String
的组成部分类型,您可以改用Collection.toArray(Object[])
:String[] elements = Arrays.asList("two", "one").toArray(new String[0]);
语言代码处理方面的变更:使用
Locale
API 时,希伯来语、意第绪语和印度尼西亚语的语言代码不再转换为过时的形式(希伯来语:iw
、意第绪语:ji
和印度尼西亚语:in
)。在为其中一个语言区域指定语言代码时,请改用 ISO 639-1 中的代码:yi
、Yid1(希伯来语):yi
。he
id
随机 int 序列变更:在 https://bugs.openjdk.org/browse/JDK-8301574 中做出更改后,以下
Random.ints()
方法现在返回的数字序列现在与Random.nextInt()
方法不同:通常,此变更不会导致应用破坏行为,但您的代码不应期望从
Random.ints()
方法生成的序列与Random.nextInt()
匹配。
安全
Android 15 包含一些有助于提升系统安全性的变更,以帮助保护应用和用户免受恶意应用的侵害。
安全的后台 activity 启动
Android 15 protects users from malicious apps and gives them more control over their devices by adding changes that prevent malicious background apps from bringing other apps to the foreground, elevating their privileges, and abusing user interaction. Background activity launches have been restricted since Android 10 (API level 29).
Block apps that don't match the top UID on the stack from launching activities
Malicious apps can launch another app's activity within the same task, then
overlay themselves on top, creating the illusion of being that app. This "task
hijacking" attack bypasses current background launch restrictions because it all
occurs within the same visible task. To mitigate this risk, Android 15 adds a
flag that blocks apps that don't match the top UID on the stack from launching
activities. To opt in for all of your app's activities, update the
allowCrossUidActivitySwitchFromBelow
attribute in your app's AndroidManifest.xml
file:
<application android:allowCrossUidActivitySwitchFromBelow="false" >
The new security measures are active if all of the following are true:
- The app performing the launch targets Android 15.
- The app on top of the task stack targets Android 15.
- Any visible activity has opted in to the new protections
If the security measures are enabled, apps might return home, rather than the last visible app, if they finish their own task.
Other changes
In addition to the restriction for UID matching, these other changes are also included:
- Change
PendingIntent
creators to block background activity launches by default. This helps prevent apps from accidentally creating aPendingIntent
that could be abused by malicious actors. - Don't bring an app to the foreground unless the
PendingIntent
sender allows it. This change aims to prevent malicious apps from abusing the ability to start activities in the background. By default, apps are not allowed to bring the task stack to the foreground unless the creator allows background activity launch privileges or the sender has background activity launch privileges. - Control how the top activity of a task stack can finish its task. If the top activity finishes a task, Android will go back to whichever task was last active. Moreover, if a non-top activity finishes its task, Android will go back to the home screen; it won't block the finish of this non-top activity.
- Prevent launching arbitrary activities from other apps into your own task. This change prevents malicious apps from phishing users by creating activities that appear to be from other apps.
- Block non-visible windows from being considered for background activity launches. This helps prevent malicious apps from abusing background activity launches to display unwanted or malicious content to users.
更安全的 intent
Android 15 引入了新的安全措施,使 intent 更加安全可靠。这些变更旨在防止潜在漏洞和被恶意应用利用的 intent 滥用。Android 15 中对 intent 的安全性进行了两项主要改进:
- 匹配目标 intent 过滤器:定位特定组件的 intent 必须准确匹配目标的 intent 过滤器规范。如果您通过发送 intent 来启动其他应用的 activity,则目标 intent 组件需要与接收 activity 声明的 intent 过滤器保持一致。
- intent 必须具有操作:没有操作的 intent 将不再与任何 intent 过滤器匹配。这意味着,用于启动 activity 或服务的 intent 必须具有明确定义的操作。
- 待处理 intent:待处理 intent 的创建者被视为封装 intent 的发送者,而非待处理 intent 的发送者
Kotlin
fun onCreate() { StrictMode.setVmPolicy(VmPolicy.Builder() .detectUnsafeIntentLaunch() .build() ) }
Java
public void onCreate() { StrictMode.setVmPolicy(new VmPolicy.Builder() .detectUnsafeIntentLaunch() .build()); }
用户体验和系统界面
Android 15 包含一些旨在打造更一致、更直观的用户体验的变更。
窗口边衬区更改
Android 15 中有两个与窗口边衬区相关的变更:默认强制执行无边框模式;还存在配置变更,例如系统栏的默认配置。
Edge-to-edge enforcement
Apps are edge-to-edge by default on devices running Android 15 if the app is targeting Android 15 (API level 35).
This is a breaking change that might negatively impact your app's UI. The changes affect the following UI areas:
- Gesture handle navigation bar
- Transparent by default.
- Bottom offset is disabled so content draws behind the system navigation bar unless insets are applied.
setNavigationBarColor
andR.attr#navigationBarColor
are deprecated and don't affect gesture navigation.setNavigationBarContrastEnforced
andR.attr#navigationBarContrastEnforced
continue to have no effect on gesture navigation.
- 3-button navigation
- Opacity set to 80% by default, with color possibly matching the window background.
- Bottom offset disabled so content draws behind the system navigation bar unless insets are applied.
setNavigationBarColor
andR.attr#navigationBarColor
are set to match the window background by default. The window background must be a color drawable for this default to apply. This API is deprecated but continues to affect 3-button navigation.setNavigationBarContrastEnforced
andR.attr#navigationBarContrastEnforced
is true by default, which adds an 80% opaque background across 3-button navigation.
- Status bar
- Transparent by default.
- The top offset is disabled so content draws behind the status bar unless insets are applied.
setStatusBarColor
andR.attr#statusBarColor
are deprecated and have no effect on Android 15.setStatusBarContrastEnforced
andR.attr#statusBarContrastEnforced
are deprecated but still have an effect on Android 15.
- Display cutout
layoutInDisplayCutoutMode
of non-floating windows must beLAYOUT_IN_DISPLAY_CUTOUT_MODE_ALWAYS
.SHORT_EDGES
,NEVER
andDEFAULT
are interpreted asALWAYS
so that users don't see a Black bar caused by the display cutout and appear edge-to-edge.
The following example shows an app before and after targeting Android 15 (API level 35), and before and after applying insets.
What to check if your app is already edge-to-edge
If your app is already edge-to-edge and applies insets, you are mostly unimpacted, except in the following scenarios. However, even if you think you aren't impacted, we recommend you test your app.
- You have a non-floating window, such as an
Activity
that usesSHORT_EDGES
,NEVER
orDEFAULT
instead ofLAYOUT_IN_DISPLAY_CUTOUT_MODE_ALWAYS
. If your app crashes on launch, this might be due to your splashscreen. You can either upgrade the core splashscreen dependency to 1.2.0-alpha01 or later or setwindow.attributes.layoutInDisplayCutoutMode = WindowManager.LayoutInDisplayCutoutMode.always
. - There might be lower-traffic screens with occluded UI. Verify these
less-visited screens don't have occluded UI. Lower-traffic screens include:
- Onboarding or sign-in screens
- Settings pages
What to check if your app is not already edge-to-edge
If your app is not already edge-to-edge, you are most likely impacted. In addition to the scenarios for apps that are already edge-to-edge, you should consider the following:
- If your app uses Material 3 Components (
androidx.compose.material3
) in compose, such asTopAppBar
,BottomAppBar
, andNavigationBar
, these components are likely not impacted because they automatically handle insets. - If your app is using Material 2 Components (
androidx.compose.material
) in Compose, these components don't automatically handle insets. However, you can get access to the insets and apply them manually. In androidx.compose.material 1.6.0 and later, use thewindowInsets
parameter to apply the insets manually forBottomAppBar
,TopAppBar
,BottomNavigation
, andNavigationRail
. Likewise, use thecontentWindowInsets
parameter forScaffold
. - If your app uses views and Material Components
(
com.google.android.material
), most views-based Material Components such asBottomNavigationView
,BottomAppBar
,NavigationRailView
, orNavigationView
, handle insets and require no additional work. However, you need to addandroid:fitsSystemWindows="true"
if usingAppBarLayout
. - For custom composables, apply the insets manually as padding. If your
content is within a
Scaffold
, you can consume insets using theScaffold
padding values. Otherwise, apply padding using one of theWindowInsets
. - If your app is using views and
BottomSheet
,SideSheet
or custom containers, apply padding usingViewCompat.setOnApplyWindowInsetsListener
. ForRecyclerView
, apply padding using this listener and also addclipToPadding="false"
.
What to check if your app must offer custom background protection
If your app must offer custom background protection to 3-button navigation or
the status bar, you app should place a composable or view behind the system bar
using WindowInsets.Type#tappableElement()
to get the 3-button
navigation bar height or WindowInsets.Type#statusBars
.
Additional edge-to-edge resources
See the Edge to Edge Views and Edge to Edge Compose guides for additional considerations on applying insets.
Deprecated APIs
The following APIs are now deprecated:
R.attr#enforceStatusBarContrast
R.attr#navigationBarColor
R.attr#navigationBarDividerColor
R.attr#statusBarColor
Window#getNavigationBarColor
Window#getNavigationBarDividerColor
Window#getStatusBarColor
Window#isStatusBarContrastEnforced
Window#setDecorFitsSystemWindows
Window#setNavigationBarColor
Window#setNavigationBarDividerColor
Window#setStatusBarColor
Window#setStatusBarContrastEnforced
Stable configuration
如果您的应用以 Android 15 或更高版本为目标平台,Configuration
将不再排除系统栏。如果您在 Configuration
类中使用屏幕尺寸计算布局,则应根据需要将其替换为合适的 ViewGroup
、WindowInsets
或 WindowMetricsCalculator
等更好的替代方案。
从 API 1 开始,Configuration
一直可用。它通常从 Activity.onConfigurationChanged
获取。它可提供窗口密度、方向和大小等信息。从 Configuration
返回的窗口大小的一个重要特征是它之前排除了系统栏。
配置大小通常用于资源选择(如 /res/layout-h500dp
),这仍然是一个有效的用例。不过,我们一直不建议将其用于布局计算。如果这样做,您应该立即离开。您应该根据自己的使用场景,将 Configuration
替换为更合适的代码。
如果您使用其计算布局,请使用适当的 ViewGroup
,例如 CoordinatorLayout
或 ConstraintLayout
。如果您使用它来确定系统导航栏的高度,请使用 WindowInsets
。如果您想知道应用窗口的当前大小,请使用 computeCurrentWindowMetrics
。
以下列表介绍了受此更改影响的字段:
Configuration.screenWidthDp
和screenHeightDp
尺寸不再排除系统栏。Configuration.smallestScreenWidthDp
会受到screenWidthDp
和screenHeightDp
更改的间接影响。- 在近方形设备上,对
screenWidthDp
和screenHeightDp
的更改会间接影响Configuration.orientation
。 Display.getSize(Point)
会受到Configuration
中变更的间接影响。从 API 级别 30 开始,此 API 已被废弃。- 从 API 级别 33 开始,
Display.getMetrics()
就一直以这种方式运行。
EnglishTextHeight 属性默认为 true
For apps targeting Android 15, the elegantTextHeight
TextView
attribute becomes true
by default, replacing the
compact font used by default with some scripts that have large vertical metrics
with one that is much more readable. The compact font was introduced to prevent
breaking layouts; Android 13 (API level 33) prevents many of these breakages by
allowing the text layout to stretch the vertical height utilizing the
fallbackLineSpacing
attribute.
In Android 15, the compact font still remains in the system, so your app can set
elegantTextHeight
to false
to get the same behavior as before, but it is
unlikely to be supported in upcoming releases. So, if your app supports the
following scripts: Arabic, Lao, Myanmar, Tamil, Gujarati, Kannada, Malayalam,
Odia, Telugu or Thai, test your app by setting elegantTextHeight
to true
.
复杂字母形状的 TextView 宽度变化
在以前的 Android 版本中,一些采用复杂形状的草体字体或语言可能会在上一个或下一个字符区域中绘制字母。在某些情况下,此类字母会在开始或结束位置被截断。从 Android 15 开始,TextView
会分配宽度来为此类字母绘制足够的空间,并允许应用请求左侧添加额外的内边距以防止被裁剪。
由于此变更会影响 TextView
确定宽度的方式,因此如果应用以 Android 15 或更高版本为目标平台,TextView
会默认分配更多宽度。您可以通过对 TextView
调用 setUseBoundsForWidth
API 来启用或停用此行为。
由于添加左侧内边距可能会导致现有布局未对齐,因此默认情况下,系统不会添加内边距,即使对于以 Android 15 或更高版本为目标平台的应用也是如此。不过,您可以通过调用 setShiftDrawingOffsetForStartOverhang
添加额外的内边距以防止裁剪。
以下示例展示了这些更改如何改进某些字体和语言的文本布局。
EditText 的语言区域感知型默认行高
In previous versions of Android, the text layout stretched the height of the
text to meet the line height of the font that matched the current locale. For
example, if the content was in Japanese, because the line height of the Japanese
font is slightly larger than the one of a Latin font, the height of the text
became slightly larger. However, despite these differences in line heights, the
EditText
element was sized uniformly, regardless
of the locale being used, as illustrated in the following image:
For apps targeting Android 15, a minimum line height is now reserved for
EditText
to match the reference font for the specified Locale, as shown in the
following image:
If needed, your app can restore the previous behavior by specifying the
useLocalePreferredLineHeightForMinimum
attribute
to false
, and your app can set custom minimum vertical metrics using the
setMinimumFontMetrics
API in Kotlin and Java.
摄像头和媒体
对于以 Android 15 或更高版本为目标平台的应用,Android 15 对相机和媒体行为做出了以下变更。
请求音频焦点的限制
以 Android 15 为目标平台的应用必须是热门应用或运行与音频相关的前台服务,才能请求音频焦点。如果应用在不符合其中任何一项要求时尝试请求焦点,调用会返回 AUDIOFOCUS_REQUEST_FAILED
。
如果前台服务的类型为 mediaPlayback
、camera
、microphone
或 phoneCall
,则会被视为与音频相关。
如需详细了解音频焦点,请参阅管理音频焦点。
更新后的非 SDK 限制
Android 15 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 15 为目标平台,其中一些变更可能不会立即对您产生影响。不过,虽然您的应用可以访问某些非 SDK 接口(具体取决于应用的目标 API 级别),但使用任何非 SDK 方法或字段始终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,则可以测试该应用进行确认。如果您的应用依赖于非 SDK 接口,则应开始计划迁移到 SDK 替代方案。不过,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功能找到无需使用非 SDK 接口的替代方案,则应请求新的公共 API。
如需详细了解此 Android 版本中的变更,请参阅 Android 15 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。