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Expo ScreenOrientation
用于管理设备屏幕方向的通用库。
屏幕方向是指图形在设备上绘制的方向。例如,下图中的设备处于纵向和横向两种物理方向,但屏幕方向为纵向。有关设备的物理方向,请参阅 Device Motion 的方向部分。
在 Android 和 iOS 平台上,屏幕方向的更改会覆盖任何系统设置或用户偏好。在 Android 上,可以在考虑用户偏好的方向的同时更改屏幕方向。在 iOS 上,应用无法访问用户和系统设置,因此任何屏幕方向更改都会覆盖现有设置。
Web 支持有限。
iOS 27 及更高版本中的方向锁定 iOS
从 iOS 27 开始,iPhone 应用可以调整大小,例如在 macOS 上使用 iPhone Mirroring 时,或在 iPad 上运行时。当应用可调整大小时,系统会将受支持的方向视为偏好而非要求。这会带来两个后果:
lockAsync可能不起作用。系统可以拒绝该请求,而应用仍可调整大小。getOrientationAsync可能无法反映应用所绘制窗口的形状。无论窗口的宽高比如何,iPhone Mirroring 始终报告纵向方向。
请设计能够适应可用空间的屏幕,而不要依赖固定方向。在调试版本中,如果系统拒绝方向锁定,此库会记录警告。利用这些警告找出仍依赖平台不再保证的方向锁定的屏幕。
安装
If you are installing this in an existing React Native app, make sure to install expo in your project.
警告
Apple 在 iOS 9 中为 iPad 添加了对 分屏视图 模式的支持。这改变了系统处理屏幕方向的方式。简而言之,对于 iOS,除非你并排打开两个应用,否则 iPad 始终处于横向模式。若要使用此模块锁定屏幕方向,需要通过在应用配置中将 ios.requireFullScreen 设置为 true,禁用对此功能的支持。
在 iOS 27 及更高版本中,requireFullScreen 不再阻止应用调整大小,因此无法可靠地锁定屏幕方向。请参阅 iOS 27 及更高版本中的方向锁定。有关 分屏视图 模式的更多信息,请参阅 Apple 官方文档。
在应用配置中配置
如果项目中使用配置插件(Continuous Native Generation (CNG)),可以使用内置的配置插件配置 expo-screen-orientation。该插件允许你配置各种无法在运行时设置、且需要重新构建应用二进制文件才能生效的属性。如果应用不使用 CNG,则需要手动配置此库。
Example app.json with config plugin
Configurable properties
Are you using this library in an existing React Native app?
- 在 Xcode 中使用
xed ios打开 ios 目录。如果该目录不存在,请运行npx expo prebuild -p ios生成。 - 在 Xcode 中勾选
Requires Full Screen复选框。它应位于 Project Target > General > Deployment Info 下。
使用 Expo Router 设置每个屏幕的方向
如果使用 Expo Router,可以通过 Stack.Screen 上的 orientation 选项为每个屏幕设置方向。此功能由 react-native-screens 提供支持,也是堆栈导航器中为每个屏幕设置方向的推荐方法。
API
import * as ScreenOrientation from 'expo-screen-orientation';
Methods
Gets the current screen orientation.
Promise<Orientation>Returns a promise that fulfils with an Orientation
value that reflects the current screen orientation.
Gets the current screen orientation lock type.
Promise<OrientationLock>Returns a promise which fulfils with an OrientationLock
value.
Gets the platform specific screen orientation lock type.
Promise<PlatformOrientationInfo>Returns a promise which fulfils with a PlatformOrientationInfo
value.
Lock the screen orientation to a particular OrientationLock.
Promise<void>Returns a promise with void value, which fulfils when the orientation is set.
Example
async function changeScreenOrientation() { await ScreenOrientation.lockAsync(ScreenOrientation.OrientationLock.LANDSCAPE_LEFT); }
Promise<void>Returns a promise with void value, resolving when the orientation is set and rejecting
if an invalid option or value is passed.
Returns whether the OrientationLock policy is supported on
the device.
Promise<boolean>Returns a promise that resolves to a boolean value that reflects whether or not the
orientationLock is supported.
Sets the screen orientation back to the OrientationLock.DEFAULT policy.
Promise<void>Returns a promise with void value, which fulfils when the orientation is set.
Event subscriptions
Invokes the listener function when the screen orientation changes from portrait to landscape
or from landscape to portrait. For example, it won't be invoked when screen orientation
change from portrait up to portrait down, but it will be called when there was a change from
portrait up to landscape left.
EventSubscriptionDeprecated: this function will be removed in a future version. Use
subscription.remove()instead.
Unsubscribes the listener associated with the Subscription object from all orientation change
updates.
voidDeprecated: this function will be removed in future versions. Keep track of your own subscriptions.
Removes all listeners subscribed to orientation change updates.
voidInterfaces
A subscription object that allows to conveniently remove an event listener from the emitter.
Types
Enums
Orientation.UNKNOWN = 0An unknown screen orientation. For example, the device is flat, perhaps on a table.
An enum whose values can be passed to the lockAsync
method.
Note:
OrientationLock.ALLandOrientationLock.PORTRAITare invalid on devices which don't supportOrientationLock.PORTRAIT_DOWN.
OrientationLock.DEFAULT = 0The default orientation. On iOS, this will allow all orientations except Orientation.PORTRAIT_DOWN.
On Android, this lets the system decide the best orientation.
OrientationLock.OTHER = 8A platform specific orientation. This is not a valid policy that can be applied in lockAsync.
OrientationLock.UNKNOWN = 9An unknown screen orientation lock. This is not a valid policy that can be applied in lockAsync.
Each iOS device has a default set of size classes that you can use as a guide when designing your interface.
An enum representing the lock policies that can be applied on the web platform, modelled after
the W3C specification.
These values can be applied through the lockPlatformAsync
method.