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React Native ListView不会更新数据更改

[英]React Native ListView not updating on data change

我不确定为什么在我的数据发生变化时ListView没有更新。 我已经将代码条带化,以便于阅读和创建一个rnplay:

https://rnplay.org/apps/ivG0mg

我期望发生的是,用户单击列表项并切换行的bool isCollapsed使背景isCollapsed红色。 实际发生的是数据源已更新但列表视图无法识别更改并且未呈现任何新内容。 有任何想法吗?

'use strict';

var React = require('react-native');

var {
    ScrollView,
    Text,
    Image,
    StyleSheet,
    TouchableHighlight,
    AppRegistry,
    View,
    ListView,
} = React;

var styles = StyleSheet.create({
    container: {
        flex: 1,
        flexDirection: 'column',
        padding: 15,
    },
    red: {
        backgroundColor: "red",
    }
});

var foods = [
    {key: 'Almond Milk (Homemade)', details:''},
    {key: 'Club Soda', details:'', isCollapsed: true},
    {key: 'Coconut Milk/Cream', details:''},
    {key: 'Coconut Water', details:''},
    {key: 'Coffee/Espresso', details:'', isCollapsed: true},
    {key: 'Fruit Juice', details:''},
    {key: 'Kombucha', details:''},
    {key: 'Mineral Water', details:''},
    {key: 'Unsweetened Tea', details:''},
    {key: 'Water', details:''},
    {key: 'Fruit Juice', details:''},
    {key: 'Kombucha', details:''},
    {key: 'Mineral Water', details:''},
    {key: 'Unsweetened Tea', details:''},
    {key: 'Water', details:''},
    {key: 'Fruit Juice', details:''},
    {key: 'Kombucha', details:''},
    {key: 'Mineral Water', details:''},
    {key: 'Unsweetened Tea', details:''},
    {key: 'Water', details:''},
    {key: 'Fruit Juice', details:''},
    {key: 'Kombucha', details:''},
    {key: 'Mineral Water', details:''},
    {key: 'Unsweetened Tea', details:''},
    {key: 'Water', details:''},
    {key: 'Fruit Juice', details:''},
    {key: 'Kombucha', details:''},
    {key: 'Mineral Water', details:''},
    {key: 'Unsweetened Tea', details:''},
    {key: 'Water', details:''},
];

class SampleApp extends React.Component{
    constructor(props){
        super(props);
        var ds = new ListView.DataSource({
            rowHasChanged: (row1, row2) => row1 !== row2,
        });
        this.state = {
            dataSource: ds.cloneWithRows(foods),
        };
    }
    _renderRow(data, sectionID, rowID) {
                return (
                        <TouchableHighlight 
                            style={[
                                    styles.container,
                                    data.isCollapsed && styles.red]}
                onPress={()=>this.onCollapse(rowID)}>
                <Text>{data.key}</Text>
            </TouchableHighlight>
        );
    }
    onCollapse(rowID: number) {
        console.log("rowID", rowID);
        foods[rowID].isCollapsed = !foods[rowID].isCollapsed;
        this.setState({dataSource: this.state.dataSource.cloneWithRows(foods)});
    }
    render() {
        return(
            <ListView
                style={styles.subContainer}
                dataSource={this.state.dataSource}
                renderRow={this._renderRow.bind(this)}
                initialListSize={15}/>
        )
    }
};

AppRegistry.registerComponent('SampleApp', () => SampleApp);

这是一个工作版本的链接:

https://rnplay.org/apps/GWoFWg

这些是我需要做的修改来修复它:

constructor(props){
    super(props);
    var ds = new ListView.DataSource({
        rowHasChanged: (row1, row2) => row1 !== row2,
    });
    this.state = {
        dataSource: ds.cloneWithRows(foods),
        db: foods,
    };
}

还有这个:

onCollapse(rowID: number) {
    var newArray = this.state.db.slice();
    newArray[rowID] = {
        key: newArray[rowID].key,
        details: newArray[rowID].details,
        isCollapsed: newArray[rowID].isCollapsed == false ? true : false,
    };
    this.setState({
        dataSource: this.state.dataSource.cloneWithRows(newArray),
        db: newArray,
    });
}

看起来这将是您需要的解决方案React-Native Updating List View DataSource

但我玩了一下它也无法使它工作。 https://rnplay.org/apps/sk_ukQ

不确定它是否会有所帮助,但我尝试将此数组设置为空白并且能够清除整个列表... this.setState({dataSource:this.state.dataSource.cloneWithRows([])});

我认为由于某种原因它使用原始数组的缓存版本而不是更新的数组。 只是不确定为什么。

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