Reactjs 如何在类组件中使用React forwardRef和React redux?
如何使用带有连接功能的Reactjs 如何在类组件中使用React forwardRef和React redux?,reactjs,react-native,react-redux,react-forwardref,Reactjs,React Native,React Redux,React Forwardref,如何使用带有连接功能的react-redux的类内组件forwardRef import React, { Component } from 'react'; import ChildComponent from './ChildComponent'; class ParentComponent extends Component { constructor(props) { super(props); this.myRef = React.createRef(); } re
react-redux
的类内组件forwardRef
import React, { Component } from 'react';
import ChildComponent from './ChildComponent';
class ParentComponent extends Component {
constructor(props) {
super(props);
this.myRef = React.createRef();
}
render() {
return <ChildComponent ref={this.myRef} />;
}
}
export default ParentComponent;
import React,{Component}来自'React';
从“/ChildComponent”导入ChildComponent;
类ParentComponent扩展组件{
建造师(道具){
超级(道具);
this.myRef=React.createRef();
}
render(){
返回;
}
}
导出默认父组件;
子组件
import React, { Component } from 'react';
import { TextInput } from 'react-native';
import { connect } from 'react-redux';
class ChildComponent extends Component {
render() {
return <TextInput value={'Hi'} ref={??} />;
}
}
export default connect(null, null, null, { forwardRef: true })(ChildComponent);
import React,{Component}来自'React';
从“react native”导入{TextInput};
从'react redux'导入{connect};
类ChildComponent扩展组件{
render(){
返回;
}
}
导出默认连接(null,null,null,{forwardRef:true})(ChildComponent);
我不知道如何在类组件中使用
React.forwardRef()
。connect
函数是一个高阶组件。您可以按照中的步骤来更好地理解HOC如何将ref转发到已包装组件
要点是react ref不是道具,它像react键一样特殊,但必要时可以将它们作为道具传递{forwardRef:true}
连接的connect
选项将只将ref
转发到包装的组件,在本例中为ChildComponent
。相反,您希望进一步“传递”一个ref,并将其附加到ChildComponent
的子组件
forwardedRef
传递给子组件class ParentComponent extends Component {
constructor(props) {
super(props);
this.myRef = React.createRef(); // <-- (1)
}
render() {
return <ChildComponent forwardedRef={this.myRef} />; // <-- (2)
}
}
class ChildComponent extends Component {
render() {
const { forwardedRef } = this.props; // <-- (3a)
return <TextInput ref={forwardedRef} value={'Hi'} />; // <-- (3b)
}
}
类ParentComponent扩展组件{
建造师(道具){
超级(道具);
this.myRef=React.createRef()//