Redux模块化拆分reducer函数流程介绍

// 导入redux中的createStore创建仓库数据的方法
// combineReducers 用来合并多个拆分后的 reducer方式,返回一个新 reducer
// applyMiddleware 扩展redux功能
import { createStore, combineReducers, applyMiddleware } from 'redux'
// 配合浏览器安装的插件来进行redux调试所用  
// 开发时有用，生产要关闭
import { composeWithDevTools } from '@redux-devtools/extension'
// 导入拆分开的模块
import count from './reducers/count'
import film from './reducers/film'
// 合并多个模块中的 reducer 函数，并且返回一个新的 reducer 函数
const reducer = combineReducers({
  // key:value
  // key：它是在获取 state 数据时的命名空间名称，redux 中没有 dispatch 操作的命名空间名称
  // 如果你进行了 redux 模块化拆分，则需要注意 type 的类型名称不能重名，如果重名则都会执行
  // type: 以拆分后的文件名称为前缀：xxx_type 类型名，不会重名
  // value：拆分后的 reducr 纯函数
  count,
  film
})
const store = createStore(
  reducer,
  composeWithDevTools()
)
// 导出
export default store

// 计数模块
// 初始state数据
const initState = {
  num: 100
}
// 定义一个纯函数reducer，专门用来操作state中的数据,要返回一个新的state
const reducer = (state = initState, action) => {
  if (action.type === 'count_add_num') return { ...state, num: state.num + action.payload }
  return state;
}
// 导出
export default reducer

// 电影列表展示模块
// 初始state数据
const initState = {
  nowplayings: []
}
// 定义一个纯函数reducer，专门用来操作state中的数据,要返回一个新的state
const reducer = (state = initState, action) => {
  if (action.type === 'film_set_nowplayings') return { ...state, nowplayings: action.payload }
  return state;
}
// 导出
export default reducer

import { connect } from 'react-redux'
// todo... 一会要配置路径别名，它引入时就会短一些
// import countAction from '../../store/actionCreators/countAction'
import countAction from '@/store/actionCreators/countAction'
const mapDispatchToProps = dispatch => ({
  ...countAction(dispatch)
})
export default connect(state => state.count, mapDispatchToProps)

export default dispatch => ({
  add(n = 1) {
    dispatch({ type: 'count_add_num', payload: n })
  }
})

import React, { Component } from 'react'
import { Switch, Route, Link } from 'react-router-dom'
import Count from './views/Count'
import Nowplaying from './views/Nowplaying'
class App extends Component {
  render() {
    return (
      <div>
        <div>
          <Link to='/nowplaying'>nowplaying</Link> -- 
          <Link to='/count'>count</Link>
        </div>
        <hr />
        {/* 定义路由规则 */}
        <Switch>
          <Route path="/nowplaying" component={Nowplaying} />
          <Route path="/count" component={Count} />
        </Switch>
      </div>
    )
  }
}
export default App

// 计数组件
import React, { Component } from 'react'
import connect from './connect'
@connect
class Count extends Component {
  render() {
    return (
      <div>
        <h3>{this.props.num}</h3>
        <button onClick={() => this.props.add()}>累加NUM</button>
      </div>
    )
  }
}
export default Count

import { connect } from 'react-redux'
import filmAction from '@/store/actionCreators/filmAction'
export default connect(state => state.film, dispatch => filmAction(dispatch))

import { getNowPlayingFilmListApi } from '@/api/filmApi'
export default dispatch => ({
  add(page = 1) {
    getNowPlayingFilmListApi(page).then(ret => {
      dispatch({ type: 'film_set_nowplayings', payload: ret.data.films })
    })
  }
})
// async 和 await 写法
// export default dispatch => ({
//   async add(page = 1) {
//     let ret = await getNowPlayingFilmListApi(page)
//     dispatch({ type: 'film_set_nowplayings', payload: ret.data.films })
//   }
// })

import { get } from '@/utils/http'
export const getNowPlayingFilmListApi = (page = 1) => {
  return get(`/api/v1/getNowPlayingFilmList?cityId=110100&pageNum=${page}&pageSize=10`)
}

// 电影展示列表组件
import React, { Component } from 'react'
import connect from './connect'
@connect
class Nowplaying extends Component {
  componentDidMount() {
    this.props.add()
  }
  render() {
    return (
      <div>
        {this.props.nowplayings.length === 0 ? (
          <div>加载中...</div>
        ) : (
          this.props.nowplayings.map(item => <div key={item.filmId}>{item.name}</div>)
        )}
      </div>
    )
  }
}
export default Nowplaying

// 导入redux中的createStore创建仓库数据的方法
// combineReducers 用来合并多个拆分后的 reducer方式,返回一个新 reducer
// applyMiddleware 扩展redux功能
import { createStore, combineReducers, applyMiddleware } from 'redux'
// 配合浏览器安装的插件来进行redux调试所用  
// 开发时有用，生产要关闭
import { composeWithDevTools } from '@redux-devtools/extension'
// 导入拆分开的模块
import count from './reducers/count'
import film from './reducers/film'
import thunk from 'redux-thunk'
// 合并多个模块中的 reducer 函数，并且返回一个新的 reducer 函数
const reducer = combineReducers({
  count,
  film
})
const store = createStore(
  reducer,
  composeWithDevTools(applyMiddleware(thunk))
)
// 导出
export default store

import { connect } from 'react-redux'
// actions 这是一个对象 {a:funtion(){}}
import * as actions from '@/store/actionCreators/filmAction'
export default connect(state => state.film, actions)

import { getNowPlayingFilmListApi } from '@/api/filmApi'
const addActionCreator = data => ({ type: 'film_set_nowplayings', payload: data })
// 异步
export const add = (page = 1) => async dispatch => {
  let ret = await getNowPlayingFilmListApi(page)
  dispatch(addActionCreator(ret.data.films))
}