我试图通过" var result"将login.php的文本内容打印到屏幕上,但是获取功能不会改变" var result"的值。如何设置获取函数输出的结果值?
import React, { Component } from 'react';
import {
StyleSheet,
Text,
View,
StatusBar,
} from 'react-native';
import Logo from '../components/Logo';
import Form from '../components/Form';
import loginapi from '../apis/loginapi';
var result='noresult';
export default class Login extends Component<{}> {
render() {
login();
return (
<View style={styles.container}>
<Logo/>
<Form/>
<Text>
{result}
</Text>
<Text>
</Text></View>
);
}
}
function login() {
result = fetch('https://www.skateandstrike.com/loginsv/login.php').then((text) => {return text;});
}
const styles = StyleSheet.create({
container : {
backgroundColor:'#f05545',
flex: 1,
alignItems:'center',
justifyContent:'center',
}
});
function myFunction() {
this.setState({ showLoading: false });
}
&#13;
这也不起作用,使用setState:
import React, { Component } from 'react';
import {
StyleSheet,
Text,
View,
StatusBar,
} from 'react-native';
import Logo from '../components/Logo';
import Form from '../components/Form';
import loginapi from '../apis/loginapi';
export default class Login extends Component<{}> {
constructor(){
super();
this.state = {
data:'NoData',
}
}
render() {
login();
return (
<View style={styles.container}>
<Logo/>
<Form/>
<Text>
{this.state.data}
</Text>
</View>
);
}
}
function login() {
fetch('https://www.skateandstrike.com/loginsv/login.php').then(data => this.setState(data));
}
const styles = StyleSheet.create({
container : {
backgroundColor:'#f05545',
flex: 1,
alignItems:'center',
justifyContent:'center',
}
});
function myFunction() {
this.setState({ showLoading: false });
}
&#13;
我是否以错误的方式使用setState?在此先感谢您的帮助。
答案 0 :(得分:1)
使用fetch api时,id建议使用promise,
如果需要你解析它然后你设置状态。
React重新渲染状态/道具变化。这是反应101 btw
快速帮助:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/dynamic_layout"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
.........
</LinearLayout>
记得在构造函数中设置状态。