一、代码

 1 import React, { Component } from 'react';
 2 import {
 3     AppRegistry,
 4     StyleSheet,
 5     Text,
 6     View
 7 } from 'react-native';
 8 
 9 //默认应用的容器组件
10 export default class App extends Component {
11 
12     //构造函数
13     constructor(props) {
14         super(props);
15         this.state = {
16             responseText: null
17         };
18     }
19 
20     //渲染
21     render() {
22         return (
23             <View style={styles.container}>
24                 <Text style={styles.item} onPress={this.doXMLHttpRequest.bind(this)}>获取数据</Text>
25                 <Text>{this.state.responseText}</Text>
26             </View>
27         );
28     }
29 
30     //使用XMLHttpRequest请求数据
31     doXMLHttpRequest(){
32         var request = new XMLHttpRequest();
33         request.onreadystatechange = (e) => {
34             if (request.readyState !== 4) {
35                 return;
36             }
37 
38             if (request.status === 200) {
39                 alert("请求成功！");
40                 this.setState({responseText: request.responseText})
41                 console.log(request.responseText);
42 
43             } else {
44                 alert("请求失败！");
45             }
46         };
47 
48         request.open('GET', 'https://httpbin.org/get');
49         request.send();
50     }
51 }
52 
53 //样式定义
54 const styles = StyleSheet.create({
55     container:{
56         flex: 1,
57         marginTop:25
58     },
59     item:{
60         margin:15,
61         height:30,
62         borderWidth:1,
63         padding:6,
64         borderColor:'#ddd',
65         textAlign:'center'
66     },
67 });

二、效果图