与之前的版本一样,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
We are making the following changes to foreground services with Android 15.
- Data sync foreground service timeout behavior
- New media processing foreground service type
- Restrictions on
BOOT_COMPLETED
broadcast receivers launching foreground services - Restrictions on starting foreground services while an app holds the
SYSTEM_ALERT_WINDOW
permission
Data sync foreground service timeout behavior
Android 15 introduces a new timeout behavior to dataSync
for apps targeting
Android 15 (API level 35) or higher. This behavior also applies to the new
mediaProcessing
foreground service type.
The system permits an app's dataSync
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()
. When Service.onTimeout()
is called, the
service is no longer considered a foreground service. 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 dataSync did not stop within its timeout: [component name]"
To avoid problems with this behavior change, you can do one or more 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
dataSync
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
dataSync
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
dataSync
foreground service, use an alternative API.
If your app's dataSync
foreground services have run for 6 hours in the last
24, you cannot start another dataSync
foreground service unless the user
has brought your app to the foreground (which resets the timer). If you try to
start another dataSync
foreground service, the system throws
ForegroundServiceStartNotAllowedException
with an error message like "Time limit already exhausted for foreground service
type dataSync".
Testing
To test your app's behavior, you can enable data sync 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
New media processing foreground service type
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 media_processing_fgs_timeout_duration duration-in-milliseconds
Restrictions on BOOT_COMPLETED
broadcast receivers launching foreground services
在启动 BOOT_COMPLETED
广播接收器方面存在新限制
前台服务。BOOT_COMPLETED
接收器不能启动
以下类型的前台服务:
dataSync
camera
mediaPlayback
phoneCall
mediaProjection
microphone
(自 Android 14 起,microphone
就受到此限制)
如果 BOOT_COMPLETED
接收器尝试启动任何上述类型的前台
服务,系统会抛出 ForegroundServiceStartNotAllowedException
。
测试
如需测试应用的行为,您可以启用这些新限制,即使您的应用并未以 Android 15 为目标平台(只要应用在 Android 15 设备上运行)也是如此。运行以下 adb
命令:
adb shell am compat enable FGS_BOOT_COMPLETED_RESTRICTIONS your-package-name
如需在不重启设备的情况下发送 BOOT_COMPLETED
广播,请运行以下 adb
命令:
adb shell am broadcast -a android.intent.action.BOOT_COMPLETED your-package-name
Restrictions on starting foreground services while an app holds the SYSTEM_ALERT_WINDOW
permission
以前,如果应用拥有 SYSTEM_ALERT_WINDOW
权限,即使应用当前在后台运行,也可以启动前台服务(如免于后台启动限制中所述)。
如果应用以 Android 15 为目标平台,则此豁免范围现在更窄。现在,应用需要具有 SYSTEM_ALERT_WINDOW
权限,并且还需要有一个可见的叠加窗口。也就是说,应用需要先启动 TYPE_APPLICATION_OVERLAY
窗口,并且该窗口需要处于可见状态,然后您才能启动前台服务。
如果您的应用尝试从后台启动前台服务,但不符合这些新要求(并且没有其他豁免情况),系统会抛出 ForegroundServiceStartNotAllowedException
。
如果您的应用声明了 SYSTEM_ALERT_WINDOW
权限并从后台启动前台服务,则可能会受到此变更的影响。如果您的应用获得了 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有有效的叠加层窗口。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。
测试
如需测试应用的行为,您可以启用这些新限制,即使您的应用并未以 Android 15 为目标平台(只要应用在 Android 15 设备上运行)也是如此。如需针对从后台启动前台服务启用这些新限制,请运行以下 adb
命令:
adb shell am compat enable FGS_SAW_RESTRICTIONS your-package-name
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 (API level 35) and higher 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 API 变更
Android 15 continues the work of refreshing Android's core libraries to align with the features in the latest OpenJDK LTS releases.
Some of these changes can affect app compatibility for apps targeting Android 15 (API level 35):
Changes to string formatting APIs: Validation of argument index, flags, width, and precision are now more strict when using the following
String.format()
andFormatter.format()
APIs:String.format(String, Object[])
String.format(Locale, String, Object[])
Formatter.format(String, Object[])
Formatter.format(Locale, String, Object[])
For example, the following exception is thrown when an argument index of 0 is used (
%0
in the format string):IllegalFormatArgumentIndexException: Illegal format argument index = 0
In this case, the issue can be fixed by using an argument index of 1 (
%1
in the format string).Changes to component type of
Arrays.asList(...).toArray()
: When usingArrays.asList(...).toArray()
, the component type of the resulting array is now anObject
—not the type of the underlying array's elements. So the following code throws aClassCastException
:String[] elements = (String[]) Arrays.asList("one", "two").toArray();
For this case, to preserve
String
as the component type in the resulting array, you could useCollection.toArray(Object[])
instead:String[] elements = Arrays.asList("two", "one").toArray(new String[0]);
Changes to language code handling: When using the
Locale
API, language codes for Hebrew, Yiddish, and Indonesian are no longer converted to their obsolete forms (Hebrew:iw
, Yiddish:ji
, and Indonesian:in
). When specifying the language code for one of these locales, use the codes from ISO 639-1 instead (Hebrew:he
, Yiddish:yi
, and Indonesian:id
).Changes to random int sequences: Following the changes made in https://bugs.openjdk.org/browse/JDK-8301574, the following
Random.ints()
methods now return a different sequence of numbers than theRandom.nextInt()
methods do:Generally, this change shouldn't result in app-breaking behavior, but your code shouldn't expect the sequence generated from
Random.ints()
methods to matchRandom.nextInt()
.
The new SequencedCollection
API can affect your app's compatibility
after you update compileSdk
in your app's build configuration to use
Android 15 (API level 35):
Collision with
MutableList.removeFirst()
andMutableList.removeLast()
extension functions inkotlin-stdlib
The
List
type in Java is mapped to theMutableList
type in Kotlin. Because theList.removeFirst()
andList.removeLast()
APIs have been introduced in Android 15 (API level 35), the Kotlin compiler resolves function calls, for examplelist.removeFirst()
, statically to the newList
APIs instead of to the extension functions inkotlin-stdlib
.If an app is re-compiled with
compileSdk
set to35
andminSdk
set to34
or lower, and then the app is run on Android 14 and lower, a runtime error is thrown:java.lang.NoSuchMethodError: No virtual method removeFirst()Ljava/lang/Object; in class Ljava/util/ArrayList;
The existing
NewApi
lint option in Android Gradle Plugin can catch these new API usages../gradlew lint
MainActivity.kt:41: Error: Call requires API level 35 (current min is 34): java.util.List#removeFirst [NewApi] list.removeFirst()To fix the runtime exception and lint errors, the
removeFirst()
andremoveLast()
function calls can be replaced withremoveAt(0)
andremoveAt(list.lastIndex)
respectively in Kotlin. If you're using Android Studio Ladybug | 2024.1.3 or higher, it also provides a quick fix option for these errors.Consider removing
@SuppressLint("NewApi")
andlintOptions { disable 'NewApi' }
if the lint option has been disabled.Collision with other methods in Java
New methods have been added into the existing types, for example,
List
andDeque
. These new methods might not be compatible with the methods with the same name and argument types in other interfaces and classes. In the case of a method signature collision with incompatibility, thejavac
compiler outputs a build-time error. For example:Example error 1:
javac MyList.java
MyList.java:135: error: removeLast() in MyList cannot implement removeLast() in List public void removeLast() { ^ return type void is not compatible with Object where E is a type-variable: E extends Object declared in interface ListExample error 2:
javac MyList.java
MyList.java:7: error: types Deque<Object> and List<Object> are incompatible; public class MyList implements List<Object>, Deque<Object> { both define reversed(), but with unrelated return types 1 errorExample error 3:
javac MyList.java
MyList.java:43: error: types List<E#1> and MyInterface<E#2> are incompatible; public static class MyList implements List<Object>, MyInterface<Object> { class MyList inherits unrelated defaults for getFirst() from types List and MyInterface where E#1,E#2 are type-variables: E#1 extends Object declared in interface List E#2 extends Object declared in interface MyInterface 1 errorTo fix these build errors, the class implementing these interfaces should override the method with a compatible return type. For example:
@Override public Object getFirst() { return List.super.getFirst(); }
安全
Android 15 中包含一些有助于提升系统安全性的变更,可帮助保护应用和用户免受恶意应用的侵害。
限制后台 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).
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 引入了新的可选安全措施,以提高 intent 的安全性和稳健性。这些变更旨在防止潜在的漏洞以及恶意应用可能利用的 intent 滥用行为。Android 15 对 intent 的安全性进行了两项主要改进:
- 与目标 intent 过滤器匹配:定位到特定组件的 intent 必须与目标的 intent 过滤器规范完全匹配。如果您发送 intent 来启动其他应用的 activity,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。
如需检查您的应用对这些更改的响应方式,请在应用中使用 StrictMode
。如需查看有关 Intent
使用违规行为的详细日志,请添加以下方法:
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 进行了一些更改,旨在打造更一致、更直观的用户体验。
窗口边衬区更改
There are two changes related to window insets in Android 15: edge-to-edge is enforced by default, and there are also configuration changes, such as the default configuration of system bars.
Edge-to-edge enforcement
默认情况下,如果应用以 Android 15(API 级别 35)为目标平台,在搭载 Android 15 的设备上,应用默认采用全屏。
这是一项可能会对应用的界面产生负面影响的破坏性更改。这些变更会影响以下界面区域:
- 手势处理程序导航栏
- 默认透明。
- 底部偏移量处于停用状态,因此除非应用边衬区,否则内容会在系统导航栏后面绘制。
setNavigationBarColor
和R.attr#navigationBarColor
已废弃,不会影响手势导航。setNavigationBarContrastEnforced
和R.attr#navigationBarContrastEnforced
对手势导航的影响仍然不变。
- “三按钮”导航
- 默认情况下,不透明度设置为 80%,颜色可能与窗口背景相匹配。
- 底部偏移量处于停用状态,因此除非应用了边衬区,否则内容会在系统导航栏后面绘制。
- 默认情况下,
setNavigationBarColor
和R.attr#navigationBarColor
会设置为与窗口背景相匹配。窗口背景必须是彩色可绘制对象,此默认值才能应用。此 API 已废弃,但仍会影响三按钮导航。 setNavigationBarContrastEnforced
和R.attr#navigationBarContrastEnforced
默认为 true,这会在“三按钮”导航中添加 80% 的不透明背景。
- 状态栏
- 默认透明。
- 顶部偏移量已停用,因此除非应用边衬区,否则内容绘制在状态栏后面。
setStatusBarColor
和R.attr#statusBarColor
已废弃,对 Android 15 没有任何影响。setStatusBarContrastEnforced
和R.attr#statusBarContrastEnforced
已废弃,但对 Android 15 仍有影响。
- 刘海屏
- 非浮动窗口的
layoutInDisplayCutoutMode
必须为LAYOUT_IN_DISPLAY_CUTOUT_MODE_ALWAYS
。SHORT_EDGES
、NEVER
和DEFAULT
会被解读为ALWAYS
,这样用户就不会看到由刘海屏导致的黑条,从而显示为无边框。
- 非浮动窗口的
以下示例展示了应用在以 Android 15(API 级别 35)为目标平台之前和之后,以及应用在应用内嵌之前和之后的效果。
如何检查应用是否已采用边到边设计
如果您的应用已采用边到边设计并应用了内边距,则除以下情况外,您大多不会受到影响。不过,即使您认为自己未受到影响,我们仍建议您测试自己的应用。
- 您有一个非浮动窗口,例如使用
SHORT_EDGES
、NEVER
或DEFAULT
(而非LAYOUT_IN_DISPLAY_CUTOUT_MODE_ALWAYS
)的Activity
。如果您的应用在启动时崩溃,这可能是启动画面造成的。您可以将核心启动画面依赖项升级到 1.2.0-alpha01 或更高版本,也可以设置window.attributes.layoutInDisplayCutoutMode = WindowManager.LayoutInDisplayCutoutMode.always
。 - 可能会有流量较低的屏幕显示被遮挡的界面。验证这些访问次数较少的屏幕是否存在遮挡的界面。流量较低的屏幕包括:
- 初始配置或登录屏幕
- “设置”页面
如果您的应用尚未采用边到边设计,应检查哪些方面
如果您的应用尚未采用边到边设计,您很可能受到影响。除了已经采用边到边设计的应用的场景之外,您还应考虑以下情况:
- 如果您的应用在 Compose 中使用 Material 3 组件 (
androidx.compose.material3
),例如TopAppBar
、BottomAppBar
和NavigationBar
,这些组件可能不会受到影响,因为它们会自动处理边衬区。 - 如果应用使用的是 Compose 中的 Material 2 组件 (
androidx.compose.material
),这些组件本身并不会自动处理边衬区。不过,您可以获得边衬区的访问权限,然后手动应用边衬区。在 androidx.compose.material 1.6.0 及更高版本中,使用windowInsets
参数为BottomAppBar
、TopAppBar
、BottomNavigation
和NavigationRail
手动应用边衬区。同样,请为Scaffold
使用contentWindowInsets
参数。 - 如果应用使用了 View 和 Material 组件 (
com.google.android.material
),则大多数基于 View 的 Material 组件(例如BottomNavigationView
、BottomAppBar
、NavigationRailView
或NavigationView
)都会处理边衬区,因此不需要执行额外的操作。不过,如果使用AppBarLayout
,则需要添加android:fitsSystemWindows="true"
。 - 对于自定义可组合项,请手动将边衬区应用为内边距。如果您的内容位于
Scaffold
中,您可以使用Scaffold
内边距值使用内边距。否则,请使用WindowInsets
之一应用内边距。 - 如果应用使用的是 View 和
BottomSheet
、SideSheet
或自定义容器,请使用ViewCompat.setOnApplyWindowInsetsListener
应用内边距。对于RecyclerView
,请使用此监听器应用内边距,并添加clipToPadding="false"
。
如果您的应用必须提供自定义后台保护,应检查哪些方面
如果您的应用必须为三按钮导航栏或状态栏提供自定义背景保护,则应使用 WindowInsets.Type#tappableElement()
获取三按钮导航栏高度或 WindowInsets.Type#statusBars
,将可组合项或视图放置在系统栏后面。
其他端到端资源
如需了解有关应用内边距的其他注意事项,请参阅边到边视图和边到边 Compose 指南。
已弃用的 API
以下 API 已废弃,但并未停用:
R.attr#enforceStatusBarContrast
R.attr#navigationBarColor
(适用于三按钮导航,透明度为 80%)Window#isStatusBarContrastEnforced
Window#setNavigationBarColor
(适用于 80% Alpha 版的三按钮导航)Window#setStatusBarContrastEnforced
以下 API 已弃用和停用:
R.attr#navigationBarColor
(适用于手势导航)R.attr#navigationBarDividerColor
R.attr#statusBarColor
Window#setDecorFitsSystemWindows
Window#getNavigationBarColor
Window#getNavigationBarDividerColor
Window#getStatusBarColor
Window#setNavigationBarColor
(适用于手势导航)Window#setNavigationBarDividerColor
Window#setStatusBarColor
Stable configuration
If your app targets Android 15 (API level 35) or higher, Configuration
no
longer excludes the system bars. If you use the screen size in the
Configuration
class for layout calculation, you should replace it with better
alternatives like an appropriate ViewGroup
, WindowInsets
, or
WindowMetricsCalculator
depending on your need.
Configuration
has been available since API 1. It is typically obtained from
Activity.onConfigurationChanged
. It provides information like window density,
orientation, and sizes. One important characteristic about the window sizes
returned from Configuration
is that it previously excluded the system bars.
The configuration size is typically used for resource selection, such as
/res/layout-h500dp
, and this is still a valid use case. However, using it for
layout calculation has always been discouraged. If you do so, you should move
away from it now. You should replace the use of Configuration
with something
more suitable depending on your use case.
If you use it to calculate the layout, use an appropriate ViewGroup
, such as
CoordinatorLayout
or ConstraintLayout
. If you use it to determine the height
of the system navbar, use WindowInsets
. If you want to know the current size
of your app window, use computeCurrentWindowMetrics
.
The following list describes the fields affected by this change:
Configuration.screenWidthDp
andscreenHeightDp
sizes no longer exclude the system bars.Configuration.smallestScreenWidthDp
is indirectly affected by changes toscreenWidthDp
andscreenHeightDp
.Configuration.orientation
is indirectly affected by changes toscreenWidthDp
andscreenHeightDp
on close-to-square devices.Display.getSize(Point)
is indirectly affected by the changes inConfiguration
. This was deprecated beginning in API level 30.Display.getMetrics()
has already worked like this since API level 33.
elegantTextHeight 属性的默认值为 true
For apps targeting Android 15 (API level 35), 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
In previous versions of Android, some cursive fonts or languages that have
complex shaping might draw the letters in the previous or next character's area.
In some cases, such letters were clipped at the beginning or ending position.
Starting in Android 15, a TextView
allocates width for drawing enough space
for such letters and allows apps to request extra paddings to the left to
prevent clipping.
Because this change affects how a TextView
decides the width, TextView
allocates more width by default if the app targets Android 15 (API level 35) or
higher. You can enable or disable this behavior by calling the
setUseBoundsForWidth
API on TextView
.
Because adding left padding might cause a misalignment for existing layouts, the
padding is not added by default even for apps that target Android 15 or higher.
However, you can add extra padding to preventing clipping by calling
setShiftDrawingOffsetForStartOverhang
.
The following examples show how these changes can improve text layout for some fonts and languages.
EditText 的语言区域感知默认行高
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 (API level 35), 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。
有关请求音频焦点的限制
以 Android 15 为目标平台的应用必须是顶级应用或运行前台服务,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,该调用将返回 AUDIOFOCUS_REQUEST_FAILED
。
您可以参阅管理音频焦点,详细了解音频焦点。
更新后的非 SDK 限制
Android 15 includes updated lists of restricted non-SDK interfaces based on collaboration with Android developers and the latest internal testing. Whenever possible, we make sure that public alternatives are available before we restrict non-SDK interfaces.
If your app does not target Android 15, some of these changes might not immediately affect you. However, while it's possible for your app to access some non-SDK interfaces depending on your app's target API level, using any non-SDK method or field always carries a high risk of breaking your app.
If you are unsure if your app uses non-SDK interfaces, you can test your app to find out. If your app relies on non-SDK interfaces, you should begin planning a migration to SDK alternatives. Nevertheless, we understand that some apps have valid use cases for using non-SDK interfaces. If you can't find an alternative to using a non-SDK interface for a feature in your app, you should request a new public API.
To learn more about the changes in this release of Android, see Updates to non-SDK interface restrictions in Android 15. To learn more about non-SDK interfaces generally, see Restrictions on non-SDK interfaces.