Question

我有两个类Parent类和Child类，我想从Parent类调用Child类函数。问题是我想从父标题按钮调用子类函数。我尝试了refs方法，但没有得到结果。还有其他方法吗？

子类：

 class FilterSlider extends React.Component {
    constructor(props) {
    super(props);
    console.log(props);
}

  PanelShow = () => {
    this._panel.show();
   };

  render() {
      return (
        <SlidingUpPanel
            ref={(c) => (this._panel = c)}
            draggableRange={{ top: height / 1.2, bottom: -10 }}
            animatedValue={this._draggedValue}
            showBackdrop={false}
        >
            <View style={styles.panel}>
                <View style={styles.panelHeader}>
                    <Text style={{ color: '#FFF' }}>Bottom Sheet Peek</Text>
                </View>
                <View style={styles.container}>
                    <Text>Bottom Sheet Content</Text>
                </View>
            </View>
        </SlidingUpPanel>
    );
   }
 }
export default FilterSlider;

和父类：

  class ReportsListView extends Component {
    constructor(props) {
     super(props);
   }
   componentDidMount() {
     this.props.navigation.setParams({
        openSlider : this._openSlider
    });
  }
  _openSlider() {
    this.refs.child.PaenlShow();
 }
 static navigationOptions = ({ navigation }) => {
    const { params = {} } = navigation.state;

    return {
        title            : navigation.state.params.name,
        headerLeft       : null,
        headerStyle      : {
            backgroundColor : '#4c8572'
        },
        headerRight      : (
            <View style={{ paddingLeft: 10, flexDirection: 'row' }}>
                <TouchableOpacity onPress={() => params.openSlider()}> //from this icon i want to call the child PanelShow function.
                    <Icon name="arrow-left" size={30} color="#ffffff" />
                </TouchableOpacity>
            </View>
        ),
        headerTitleStyle : {
            flex           : 1,
            color          : '#fff',
            alignItems     : 'center',
            justifyContent : 'center',
            fontWeight     : 'bold'
        }
    };
  render()
   {
   return(
      <FilterSlider ref = 'child'/>
    )
   }
 };

Answer 1

您错误地使用了ref属性。要解决此问题，您可以尝试以下操作：

父项

class ReportsListView extends Component {
    componentWillMount(){
        this.refs.child = null;
    }

    render() {
        return (
            <FilterSlider ref={(ref) => {
                this.refs.child = ref
            }}/>
        )
    }
}

现在，您可以从子组件中调用函数，例如：this.refs.child.doSomethings()。

从父标题按钮调用子组件功能

1 个答案: