类型错误：未定义不是对象 this.prop

Question

收到错误 TypeError: Undefined is not an object(evaluating 'this.props.track[this.state.selectedTrack]')

尝试为 iOS 运行我的模拟器时。我正在构建播放器。我在启动时收到的错误如下。并且代码将在播放器的正下方

任何指导将不胜感激。

import React, { Component } from 'react';

import {Player as PodCast} from './PodcastLayers/Player';

export const TRACKS = [

{

title: 'Stressed Out',

artist: 'Twenty One Pilots',

albumArtUrl: "http://36.media.tumblr.com/14e9a12cd4dca7a3c3c4fe178b607d27/tumblr_nlott6SmIh1ta3rfmo1_1280.jpg",

audioUrl: "http://russprince.com/hobbies/files/13%20Beethoven%20-%20Fur%20Elise.mp3",

},

];

export default class PodCastScreen extends React.Component {

render() {

return <PodCast tracks={TRACKS}/>

}

}

Answer 1

2 状态可能正在发生：你没有在你的道具中传递“轨道”您正在传递带有 null 或 undefined 值的“track”

Answer 2

您发布的第二个问题，您应该将类导入&nbsp;PodCastScreen为import PodCastScreen from'./PodcastLayers/Player';