react发出了action，然而却改变不了值？

Question

为什么我发出了action，然而改变不了值呢？
git: https://gitee.com/ChuanChuan3...

import React, {Component} from 'react'
import {
    ListItem,
    ListInfo,
    LoadMore
} from '../style';
import {
    connect
} from 'react-redux';
import {
    Link
} from 'react-router-dom';


class List extends Component {
    render() {
        const {
            list
        } = this.props;
        return (
            <div>
                {list}
            </div>
        )
    }
}

const mapState = (state) => {
   return {
       list: state.getIn(['home', 'topicList'])
   }
         

}

const mapDispatch = (dispatch) => {

}

export default connect(mapState, null)(List);

import React, {Component} from 'react'
import {
    connect
} from 'react-redux';
import Topic from './components/Topic';
import List from './components/List';
import Recommend from './components/Recommend';
import Writer from './components/Writer';
import {
    HomeWrapper,
    HomeLeft,
    HomeRight
} from './style';

import axios from 'axios'

class Home extends Component {
    render() {
        return (
            <HomeWrapper>
                <HomeLeft>
                    <img className='banner-img' alt='' src="//upload.jianshu.io/admin_banners/web_images/4318/60781ff21df1d1b03f5f8459e4a1983c009175a5.jpg?imageMogr2/auto-orient/strip|imageView2/1/w/1250/h/540" />
                    <Topic />
                    <List />
                </HomeLeft>
                <HomeRight>
                    <Recommend />
                    <Writer />
                </HomeRight>
                {/* { this.props.showScroll ? <BackTop onClick={this.handleScrollTop}>顶部</BackTop> : null} */}
            </HomeWrapper>
        )
    }

    componentDidMount() {
        axios.get('/v2/movie/in_theaters').then((res) => {
            const data = res.data.subjects;
            console.log(res, data, 'res')
            const action = {
                type: 'change_home_data',
                topicList: data[0].casts,
                articleList: data[0].casts,
                recommendList: data[0].directors
            }
            this.props.changeHomeData(action)
        })
    }

}

const mapDispatch = (dispatch) => ({
    changeHomeData(action) {
         console.log(action, 'action')
        dispatch(action)
    }

})


export default connect(null, mapDispatch)(Home);

Answer 1

用了immutableJs吧？immutableJs的每一个操作都会返回新的对象

state = state.merge({});

return state;

很明显，你少了一个赋值表达式（state=）