Question

Component A
this.state = {
    x: 1,
    y: 2
}

reset () {
    this.setState ({
        x: 3,
        y: 5
    })
}


render () {
    <B x = {this.state.x} y = {this.state.y} onClick = {this.reset.bind(this)}/>
}

=============================================== =========

Component B

this.state = {
    z: someMethod()
}

someMethod () {
    return this.props.x + this.props.y
}

On Click，我正在调用reset方法并更新组件A的状态但是如何重新呈现组件B.现在它不更新组件B.

Tried with 

componentWillReceiveProps (nextProps) {

    this.constructor(nextProps)
}

Answer 1

setState函数中的第二个组件也需要componentWillReceiveProps。构造函数仅在初始渲染时调用，并且如果它依赖于道具，则不应仅在构造函数中指定状态

componentWillReceiveProps (nextProps) {

    this.setState({z: nextProps.x + nextProps.y})
}

如果你想使用someMethod就像

那样

someMethod(props) {
     props? return props.x + props.y : return this.props.x + this.props.y
}

然后在componentWillReceiveProps

中

 componentWillReceiveProps (nextProps) {
    var z = someMethod(nextProps)
    this.setState({z})
}

关于一个组件的状态更改重新渲染第二个组件

1 个答案: