React Native之通過DeviceEventEmitter發(fā)送和接收事件

1 怎么實現(xiàn)發(fā)送和接收事件

理論上封裝了Android原生廣播的代碼,需要注冊和反注冊,這里用DeviceEventEmitter實現(xiàn)
//增加監(jiān)聽
DeviceEventEmitter.addListener
//取消監(jiān)聽
//this.emitter.remove();
這里可也可以通過安卓原生向頁面js發(fā)送消息,可以參考我的這篇博客


React Native之Android原生通過DeviceEventEmitter發(fā)送消息給js
 

今天還發(fā)現(xiàn)

const {navigate} = this.props;

等價于

let navigate = this.props.navigate;

 

2 測試代碼

    import React from 'react';
    import {View, Text} from 'react-native';
    import {DeviceEventEmitter} from "react-native";
     
    export default class App extends React.Component {
            
           constructor(props) {
              super(props);
              this.state = {name: '點擊我'};
           }
     
           render() {
              return (
                <View style={{flex: 1, alignItems: 'center', justifyContent: 'center'}}>
                  <Text
                  onPress={() => this._press()}
                   >{this.state.name}</Text>
                </View>
              );
           }
           componentDidMount() {
               this.emitter = DeviceEventEmitter.addListener("hello", (data) => {
               console.log("收到通知了:內容是:" + data);
               this.setState({name: data});
               });
           }
           _press = () => {
               DeviceEventEmitter.emit('hello', 'chenyu');
           }
           
           componentWillUnmount() {
               this.emitter.remove();
           }
    }

 

3 運行結果

一開始的效果

然后 點擊"點擊我"效果如下

然后日志打印如下

ReactNativeJS  I  收到通知了:內容是:chenyu

 











作者：chen.yu
深信服三年半工作經(jīng)驗，目前就職游戲廠商，希望能和大家交流和學習,
微信公眾號：編程入門到禿頭 或掃描下面二維碼
零基礎入門進階人工智能(鏈接)