这是父组件:
class Parent extends Component {
constructor(props) {
super(props);
this.state = {
news: ""
}
}
componentDidMount() {
this.updateNews();
}
updateNews = () => {
...
}
render() {
<CustomButton type="primary" />
}
这是CustomButton
:
const CustomButton = (props) => {
const {
type
} = props;
const updateItem = () => {
... // The firing of the setState should be here
}
return (
<Button
type={type}
onClick={() => {
updateItem();
}}
>{value}
</Button>
);
如何从const updateItem = () => {
的{{1}}内部触发,以便CustomButton
运行Parent
或updateNews
?
答案 0 :(得分:2)
像这样在父组件中使用componentDidUpdate。
class Parent extends Component {
constructor(props) {
super(props);
this.state = {
news: "",
fetchToggle:true
}
}
componentDidMount() {
this.updateNews();
}
componentDidUpdate(prevprops,prevstate){
if(prevstate.fetchToggle!==this.state.fetchToggle){
this.updateNews();
}
}
updateNews = () => {
...
}
fetchToggle=()=>{
this.setState({
fetchToggle:!this.state.fetchToggle;
})
}
render() {
<CustomButton type="primary" fetchToggle={this.fetchToggle} />
}
在子组件中单击按钮,调用此切换功能。
const CustomButton = (props) => {
const {
type
} = props;
const updateItem = () => {
... // The firing of the setState should be here
}
return (
<Button
type={type}
onClick={() => {
props.fetchToggle()
}}
>{value}
</Button>
);
请记住,状态切换值是每次单击时更新或获取最新数据的一种简洁,优雅的方法。
答案 1 :(得分:0)
您应该将回调函数传递给CustomButton,如下所示:
class Parent extends Component {
constructor(props) {
super(props);
this.state = {
news: ""
}
}
componentDidMount() {
this.updateNews();
}
updateNews = () => {
...
}
render() {
<CustomButton type="primary" stateUpdatingCallback={(val) => {this.setState({myVal: val})}}/>
}
const CustomButton = (props) => {
const {
type
} = props;
const updateItem = () => {
... // The firing of the setState should be here
}
return (
<Button
type={type}
onClick={() => {
this.props.stateUpdatingCallback("somevalue")
}}
>{value}
</Button>
);