無法在React Native中將類作爲函數錯誤調用

Question

我在React Native中製作ListView並獲取「無法將類作爲函數調用」錯誤。我還嘗試在課前添加「新」關鍵字，但仍然沒有解決錯誤。以下是我的代碼：

import React, {Component} from 'react'; 
import {StyleSheet, View, AppRegistry, ListView, Text} from 'react-native'; 

    class listview extends Component{ 

    constructor(props){ 
    super(props); 
    var ds = ListView.DataSource({rowHasChanged : (r1,r2) => r1!==r2}); 
    this.state = { 
    dataSource: ds.cloneWithRows(['1','2','3','4']) 
    } 
    } 

    _renderRow(rowData){ 
     return <Text>{rowData}</Text>; 
     } 

    render(){ 
    return(
    <ListView 
    dataSource = {this.state.dataSource} 
    renderRow = {this._renderRow.bind(this)} 
    /> 
    ); 
    } 
    } 
    AppRegistry.registerComponent('listview',() => listview); 

您可以看到錯誤here。我如何解決它？

Answer 1

constructor(props){ 
    super(props); 
    var ds = new ListView.DataSource({rowHasChanged : (r1,r2) => r1!==r2}); 
    //-------^^^ you forgot to place `new` keyword here. 
    this.state = { 
    dataSource: ds.cloneWithRows(['1','2','3','4']) 
    } 
}