React中setState方法无效

Question

看代码

class Background extends React.Component{    constructor(opts) {        super(opts);        this.initStatus();
    }
    initStatus() {        this.state = {            effect: false
        }
    }
    render(){        this.initStatus();        return <div className={cs({background: true, effect: this.state.effect})}>
            <div className="background-pannel">
                <div className="background-image-back"></div>
            </div>
            <div className="background-pannel">
                <div className="background-image"></div>
            </div>
        </div>
    }
    
    componentDidMount() {        this.setState({effect: true}, ()=>{            console.log(this.state.effect);
        })
    }
}export { Background }

为什么没有效果，打印出来的effect值依然是false？

Answer 1

是有效果的，不过在render里面的 this.initStatus()又重新把它设置为false了