我用onPress“handler”渲染了下列类型的列表。如何将组件引用传递给onPress回调?
我已经意识到,onPress处理程序是无用的,因为我无法获得比赛按下的参考。我得到ref是没有定义的错误。
var races = Engine.possibleRaces;
function racePressed(ref) {
console.log("REF: " + ref); // is never called
}
var races = Engine.possibleRaces;
var rowViews = [];
for (var i = 0; i < races.length; i++) {
rowViews.push(
<Text
ref={i}
onPress={() => racePressed(ref)} // ref is not defined
style={styles.raceText}>{races[i].text}
</Text>
);
}
<View style={{width: Screen.width, flexDirection:'row', flexWrap: 'wrap', alignItems: "center"}}>
{rowViews}
</View>
我也尝试着我作为参数传递。它不起作用,因为它在迭代结束后具有值。基本上它具有比赛价值。
onPress={() => racePressed(i)} // Same as races.length
编辑:
我做分离问题下面的程序。
'use strict';
import React, {
AppRegistry,
Component,
StyleSheet,
Text,
View
} from 'react-native';
let texts = [{text: "Click wrapper text1"}, {text: "Click wrapper text2"}];
class sandbox extends Component {
rowPressed(ref, i) {
console.log("rowPressed: " + ref + " " + i)
}
render() {
var rows = [];
for (var i = 0; i < texts.length; i++) {
rows.push(
<Text
ref={i}
onPress={() => this.rowPressed.bind(this, i)}
style={styles.raceText}>{texts[i].text}
</Text>
);
}
return (
<View style={styles.container}>
<View>
{rows}
</View>
</View>
);
}
}
const styles = StyleSheet.create({
container: {
flex: 1,
justifyContent: 'center',
alignItems: 'center'
}
});
AppRegistry.registerComponent('sandbox',() => sandbox);
回调不叫,丢除了没有错误以下警告
[tid:com.facebook.React.JavaScript] Warning: Each child in an array or iterator should have a unique "key" prop. Check the render method of `sandbox`. See https://fb.me/react-warning-keys for more information.
Chaining key ref来解决警告信息问题! – Markku
你能分享更多的代码吗?我应该如何更改以下代码以访问“this”? '渲染:函数(){ 功能rowPressed(ID){// 无法读取未定义 this.state.races的特性 '状态'[ID] .chosen = this.state.races [ID] .chosen ; } this.rowPressed = this.rowPressed.bind(this); ... onPress = {()=> rowPressed(i)}' – Markku