Expo KeepAwake

一个 React 组件，可防止屏幕在渲染时休眠。

Android

iOS

tvOS

Web

expo-keep-awake 提供了一个 React hook 来防止屏幕休眠，以及一对函数来强制启用此行为。

¥expo-keep-awake provides a React hook that prevents the screen from sleeping and a pair of functions to enable this behavior imperatively.

安装

¥Installation

Terminal

- npx expo install expo-keep-awake

If you are installing this in an existing React Native app (bare workflow), start by installing expo in your project. Then, follow the additional instructions as mentioned by library's README under "Installation in bare React Native projects" section.

用法

¥Usage

示例：hook

¥Example: hook

Keep Awake hook

import { useKeepAwake } from 'expo-keep-awake';
import React from 'react';
import { Text, View } from 'react-native';

export default function KeepAwakeExample() {
  useKeepAwake();
  return (
    <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
      <Text>This screen will never sleep!</Text>
    </View>
  );
}

示例：functions

¥Example: functions

Keep Awake functions

import { activateKeepAwake, deactivateKeepAwake } from 'expo-keep-awake';
import React from 'react';
import { Button, View } from 'react-native';

export default class KeepAwakeExample extends React.Component {
  render() {
    return (
      <View style={{ flex: 1, alignItems: 'center', justifyContent: 'center' }}>
        <Button onPress={this._activate} title="Activate" />
        <Button onPress={this._deactivate} title="Deactivate" />
      </View>
    );
  }

  _activate = () => {
    activateKeepAwake();
    alert('Activated!');
  };

  _deactivate = () => {
    deactivateKeepAwake();
    alert('Deactivated!');
  };
}

API

import KeepAwake from 'expo-keep-awake';

Constants

`KeepAwake.ExpoKeepAwakeTag`

Type: 'ExpoKeepAwakeDefaultTag'

Default tag, used when no tag has been specified in keep awake method calls.

Hooks

`useKeepAwake(tag, options)`

Name	Type	Description
tag (optional)	`string`	Tag to lock screen sleep prevention. If not provided, an ID unique to the owner component is used.
options (optional)	`KeepAwakeOptions`	Additional options for the keep awake hook.

A React hook to keep the screen awake for as long as the owner component is mounted. The optionally provided tag argument is used when activating and deactivating the keep-awake feature. If unspecified, an ID unique to the owner component is used. See the documentation for activateKeepAwakeAsync below to learn more about the tag argument.

Returns:

void

Methods

Deprecated use activateKeepAwakeAsync instead.

`KeepAwake.activateKeepAwake(tag)`

Name	Type	Description
tag (optional)	`string`	Tag to lock screen sleep prevention. If not provided, the default tag is used. Default: `ExpoKeepAwakeTag`

Prevents the screen from sleeping until deactivateKeepAwake is called with the same tag value.

If the tag argument is specified, the screen will not sleep until you call deactivateKeepAwake with the same tag argument. When using multiple tags for activation you'll have to deactivate each one in order to re-enable screen sleep. If tag is unspecified, the default tag is used.

Web support is limited.

Returns:

Promise<void>

`KeepAwake.activateKeepAwakeAsync(tag)`

Name	Type	Description
tag (optional)	`string`	Tag to lock screen sleep prevention. If not provided, the default tag is used. Default: `ExpoKeepAwakeTag`

Prevents the screen from sleeping until deactivateKeepAwake is called with the same tag value.

Web support is limited.

Returns:

Promise<void>

`KeepAwake.deactivateKeepAwake(tag)`

Name	Type	Description
tag (optional)	`string`	Tag to release the lock on screen sleep prevention. If not provided, the default tag is used. Default: `ExpoKeepAwakeTag`

Releases the lock on screen-sleep prevention associated with the given tag value. If tag is unspecified, it defaults to the same default tag that activateKeepAwake uses.

Returns:

Promise<void>

`KeepAwake.isAvailableAsync()`

Returns:

Promise<boolean>

true on all platforms except unsupported web browsers.

Event Subscriptions

Only for:

Web

`KeepAwake.addListener(tagOrListener, listener)`

Name	Type
tagOrListener	`string \| KeepAwakeListener`
listener (optional)	`KeepAwakeListener`

Observe changes to the keep awake timer. On web, this changes when navigating away from the active window/tab. No-op on native.

Returns:

Subscription

Example

KeepAwake.addListener(({ state }) => {
  // ...
});

Types

`KeepAwakeEvent`

Name	Type	Description
state	`KeepAwakeEventState`	Keep awake state.

`KeepAwakeListener()`

Name	Type
event	`KeepAwakeEvent`

`KeepAwakeOptions`

Name	Type	Description
listener (optional)	`KeepAwakeListener`	Only for: Web A callback that is invoked when the keep-awake state changes.
suppressDeactivateWarnings (optional)	`boolean`	The call will throw an unhandled promise rejection on Android when the original Activity is dead or deactivated. Set the value to `true` for suppressing the uncaught exception.

Expo KeepAwake

安装

用法

示例：hook

示例：functions

API

Constants

`KeepAwake.ExpoKeepAwakeTag`

Hooks

`useKeepAwake(tag, options)`

Methods

`KeepAwake.activateKeepAwake(tag)`

`KeepAwake.activateKeepAwakeAsync(tag)`

`KeepAwake.deactivateKeepAwake(tag)`

`KeepAwake.isAvailableAsync()`

Event Subscriptions

`KeepAwake.addListener(tagOrListener, listener)`

Types

`KeepAwakeEvent`

`KeepAwakeListener()`

`KeepAwakeOptions`

Enums

`KeepAwakeEventState`

`RELEASE`