redux更新了却没有重新渲染?

Question

//reducer
const initState={
    style:{left:0}
}
const Tabs=(state=initState,action)=>{
    switch (action.type){
        case 'recommend':
            Object.assign(state,{style:{left:0}})
            return state
        case 'list':
            Object.assign(state,{style:{left:'25%'}})
            return state
        default:
            return state
    }
}
export default Tabs

//组件
 export default class Tab extends Component{
    render(){
        const {style}=this.props
        return(
            <div>
                      ...
                    <div style={style}><span></span></div>
            </div>
        )
    }
}

Answer 1

const Tabs=(state=initState,action)=>{
    switch (action.type){
        case 'recommend':
            return Object.assign({style:{left:0}},state);
        case 'list':
           return Object.assign({style:{left:'25%'}},state);
        default:
            return state
    }
}

redux是覆盖式更新的不能把旧的state对象返回回去，必须是新建的对象才会更新