一个 react-router + redux  + react-redux 的例子与分析

index.js 

import React from 'react'
import ReactDom from 'react-dom'
import App from './App'
ReactDom.render(
    <App/>,
    document.getElementById('root')
)

没什么好说的

App.js : 

import React from 'react'
import { createStore, applyMiddleware } from 'redux'
import { Provider } from 'react-redux'
import thunk from 'redux-thunk'
import reducers from './reducers'
import RouterMap from './router'
let store = createStore(reducers, applyMiddleware(thunk))
const App = () => {
    return (
        <Provider store={ store }>
            <RouterMap/>
        </Provider>
    )
}
export default App

代码分析:

  1. reducers: redux 中的 reducers
  2. thunk: 异步action 的插件
  3. applyMiddleware: react 的中间件,用于添加插件
  4. RouterMap: 路由配置
  5. Provider:让所有容器组件都可以访问 store
  6. createStore: redux 生成 store 的方法

例子中的:RouterMap

import React from 'react'
// react-router 相关
import { Router, Route, Switch } from 'react-router-dom'
// 浏览器的History模式
import createHistory from 'history/createBrowserHistory'
// 生成一个redux容器的方法
import { connect } from 'react-redux'
// 一个action
import { initCity } from '../actions/userinfo'
// 组件
import Home from '../containers/Home'
import City from '../containers/City'
// 创建 history
const history = createHistory()

class App extends React.Component {
    render() {
        return (
            <Router history={ history }>
                <Switch>
                    <Route exact path="/" component={ Home }></Route>
                    <Route path="/city" component={ City }></Route>
                </Switch>
            </Router>
        )
    }
    componentDidMount() {
        this.props.initCity(cityName)
    }
}
function mapStateToProps(state) {
    return {
        userInfo: state.userInfo
    }
}
function mapDispatchToProps(dispatch, ownprops) {
    return {
        initCity: (cityName) => {
        }
    }
}
export default connect(
    mapStateToProps,
    mapDispatchToProps
)(App)

代码分析:

  • connect:
  1. 该方法接受2个参数,返回一个函数,返回的函数的参数通常 是react 组件,例子是App
  2. 参数1是函数,函数接收 store 中的 state 作为参数,通常 返回 state 中的数据,例子中的App组件可以通过 this.props.userInfo 获取数据
  3. 参数2是函数,函数接收 store 中的 dispatch作为第一个参数,通常返回提交action的一些方法,例子中的App组件可以通过 this.props.initCity(cityName) 提交action
  • <Router history={ history }> : 传递history 给所有组件,组件就可以通过 this.props.history.push('路由')跳转页面, this.props.history.goBack() 方法返回
  • <Route path="/city" component={ City }></Route> : 路由配置  

例子中的:reducers

import { combineReducers } from 'redux'

export function detailInfo(state = {}, action) {
    switch (action.type) {
        case 'GET_DETAIL_INFO':
            return {
                ...state,
                info: action.payload.info
            }
        case 'GET_COMMENT_LIST':
            return {
                ...state,
                comments: action.payload.comments
            }
        default:
            return state
    }
}

const initialState = {page: 0, likeList: [] }
export function userInfo(state = initialState, action) {
    switch (action.type) {
        case 'USER_CURRENTCITY':
            return {
                ...state,
                cityName: action.payload.cityName,
                userName: '小名'
            }
        case 'SAVE_HOMEAD':
            return {
                ...state,
                homeAd: action.payload.homeAd
            }
        case 'SAVE_LIKELIST':
            return {
                ...state,
                page: state.page + 1,
                likeList: state.likeList.concat(action.payload.likeList)
            }
        case 'SET_ISLOADINGLIKELIST_FLAG':
            return {
                ...state,
                isLoading: action.payload.isLoading
            }
        default:
            return state
    }
}

export  default combineReducers({
    userInfo,
    detailInfo
})

代码分析:combineReducers: 接收一个拆分后 reducer 函数组成的对象,返回一个新的 Reducer 函数

 

代码中的:所有action ,案例只列举:initCity

import axois from 'axios'

export function getDetailInfo(shopId) {
    return dispatch => axois.get(`/api/detail/info/${shopId}`).then((res) => {
        dispatch(saveDetailInfo(res.data))
    }).catch((error) => {
        console.log(error)
    })
}
export function saveDetailInfo(res) {
    return {
        type: 'GET_DETAIL_INFO',
        payload: {
            info: res
        }
    }
}

export function getComments(shopId) {
    return axois.get(`/api/detail/comment/${shopId}`).then((res) => {
        dispatch(saveComments(res.data))
    }).catch((error) => {
        console.log(error)
    })
}
export function saveComments(res) {
    return {
        type: 'GET_COMMENT_LIST',
        payload: {
            comments: res
        }
    }
}
  1. axois: ajax请求的插件
  2. getDetailInfo:
  • 该action 返回了一个发送ajax异步请求的函数
  • 异步请求成功后 触发一个action :  dispatch(saveDetailInfo(res.data))
  • 普通的action 通常返回一个对象,它之所以能够返回函数,是由于利用了插件“thunk'”,这个是异步action 的写法

City

import React from 'react'
import { connect } from 'react-redux'
import { updateCity } from '../../actions/userinfo'
import Header from '../../components/Header'
import CityList from '../../components/CityList'
import CurrentCity from './subpages/CurrentCity'

class City extends React.Component {
    render() {
        return (
            <div>
                <Header title="选择城市" goBack={ this.goBack.bind(this) }></Header>
                <CurrentCity currentCityName={ this.props.userInfo.cityName }></CurrentCity>
                <CityList chooseCity= { this.chooseCity.bind(this) }></CityList>
            </div>
        )
    }
    goBack() {
        this.props.history.goBack()
    }
    chooseCity(cityName) {
        localStore.setItem('USER_CURRENT_CITY', cityName)
        this.props.initCity(cityName)
        this.props.history.goBack()
    }
}

function mapStateToProps(state) {
    return {
        userInfo: state.userInfo
    }
}
function mapDispatchToProps(dispatch, ownProps) {
    return {
        initCity: (cityName) => {
            dispatch(updateCity(cityName))
        }
    }
}
export default connect(
    mapStateToProps,
    mapDispatchToProps
)(City)

goBack={ this.goBack.bind(this) } : 将组件本身的goBack方法,传递给 Header 组件 , bind的作用是:在Header组件调用该方法时,上下文为City组件的 this

Header

import React from 'react'
class Header extends React.Component {
    render() {
        return (
            <div id="common-header">
                <span className="back-icon" onClick={ this.clickHandle.bind(this) }>
                    <i className="icon-chevron-left"></i>
                </span>
                <h1>{ this.props.title }</h1>
            </div>
        )
    }
    clickHandle() {
        window.history.back()
    }
}
export default Header

Header组件并没有用connect包装,因为它是纯显示的组件,只有跟业务相关的组件,才会用connect容器包装

05-22 10:49