React native React Native:如何获取设备屏幕亮度并进行渲染
我正在创建一个React应用程序来显示设备信息。我想渲染屏幕亮度级别,而不是在控制台中。我该怎么做React native React Native:如何获取设备屏幕亮度并进行渲染,react-native,screen-brightness,React Native,Screen Brightness,我正在创建一个React应用程序来显示设备信息。我想渲染屏幕亮度级别,而不是在控制台中。我该怎么做 DeviceBrightness.getSystemBrightnessLevel().then(function(luminous) { console.log(luminous) }) 我希望渲染屏幕亮度级别,而不是显示在控制台中从“react native device brightness”导入设备亮度; import DeviceBrightness from 'react-n
DeviceBrightness.getSystemBrightnessLevel().then(function(luminous) {
console.log(luminous)
})
我希望渲染屏幕亮度级别,而不是显示在控制台中从“react native device brightness”导入设备亮度;
import DeviceBrightness from 'react-native-device-brightness';
export default class YourComponent extends React.Component {
constructor(props) {
super(props);
this.state = {
isLoaded: false,
brightness: 0
};
}
componentDidMount() {
DeviceBrightness.getSystemBrightnessLevel()
.then(luminous => {
this.setState({
brightness: luminous,
isLoaded: true,
});
});
}
render() {
const { isLoaded, brightness } = this.state;
if (!isLoaded) {
return {/*loading view*/}
} else {
return (
<Text>{brightness}</Text>
);
}
}
}
导出默认类YourComponent扩展React.Component{
建造师(道具){
超级(道具);
此.state={
isLoaded:false,
亮度:0
};
}
componentDidMount(){
DeviceBrightness.getSystemBrightnessLevel()
.然后(发光=>{
这是我的国家({
亮度:发光,
isLoaded:是的,
});
});
}
render(){
const{isLoaded,brightness}=this.state;
如果(!已加载){
返回{/*加载视图*/}
}否则{
返回(
{亮度}
);
}
}
}
}
render(){
返回(
{this.state.brightness}
);
}
}你说的“渲染”是什么意思?你的意思是在视图中显示它?这样做的方式与在React中显示其他异步内容的方式相同。使用
setState
将值置于状态,然后在渲染方法中从状态读取值。代码不起作用。其显示亮度值为零。我在componentWillMount函数中添加了一个箭头函数,代码现在起作用。这是已更改的componentWillMount函数。谢谢你的贡献。componentWillMount(){DeviceBrightness.getSystemBrightnessLevel().then((发光)=>{this.setState({brightness:Lightning,isLoaded:true,});});
import DeviceBrightness from 'react-native-device-brightness';
export default class App extends Component{
constructor(props){
super(props);
this.state = {
isLoaded: false,
brightness: 0,
};
}
componentWillMount() {
DeviceBrightness.getSystemBrightnessLevel()
.then((luminous) =>{
this.setState({
brightness: luminous,
isLoaded: true,
});
});
render() {
return (
<View style={styles.container}>
<Text style={styles.instructions}>{this.state.brightness}</Text>
</View>
);