PHP前端开发

小程序中wepy-redux的使用以及存储全局变量

百变鹏仔 1周前 (03-12) #前端问答
文章标签 全局变量

wepy里推荐使用wepy-redux存储全局变量

使用

1.初始化store

// app.wpyimport { setStore } from 'wepy-redux'import configStore from './store'const store = configStore()setStore(store) //setStore是将store注入到所有页面中
// store文件夹下的index.jsimport { createStore, applyMiddleware } from 'redux'import promiseMiddleware from 'redux-promise'import rootReducer from './reducers'export default function configStore () {  const store = createStore(rootReducer, applyMiddleware(promiseMiddleware)) //生成一个 store 对象  return store}

applyMiddleware 函数的作用就是对 store.dispatch 方法进行增强和改造
这里就是使用redux-promise来解决异步

2.page里面获取store


import { getStore } from 'wepy-redux' const store = getStore()// dispatchstore.dispatch({type: 'xx', payload: data}) //xx是reducer名字 payload就是携带的数据store.dispatch(getAllHoomInfo(store.getState().base)) //xx是action名字//获取stateconst state = store.getState()

3.连接组件

@connect({    data:(state) => state.base.data //注意这里是base下的state 所有要加上base.})

文件介绍

redux文件

type

types里是触发action的函数名称 只是存储函数名字

按照模块去创建type.js

//base.jsexport const GETALLHOMEINFO = 'GETALLHOMEINFO'

写好了函数名称 在index.js中export出来

export * from './counter'export * from './base'

reducers

随着应用变得复杂,需要对 reducer 函数 进行拆分,拆分后的每一块独立负责管理 state 的一部分
这个时候多个模块的reducer通过combineReducers合并成一个最终的 reducer 函数,

import { combineReducers } from 'redux'import base from './base'import counter from './counter'export default combineReducers({  base,  counter})

模块使用handleActions 来处理reducer,将多个相关的reducers写在一起
handleActions有两个参数:第一个是多个reducers,第二个是初始state

GETALLHOMEINFO reducer是将异步action返回的值赋值给data

//base.jsimport { handleActions } from 'redux-actions'import { GETALLHOMEINFO } from '../types/base'const initialState = {  data: {}}export default handleActions({  [GETALLHOMEINFO] (state, action) {    return {      ...state,      data: action.payload    }  }}, initialState)

actions

actions是对数据的处理

在index.js中export出来

export * from './counter'export * from './base'

createAction用来创建Action的

import { GETALLHOMEINFO } from '../types/base'import { createAction } from 'redux-actions'import { Http, Apis } from '../../libs/interface'export const getAllHoomInfo = createAction(GETALLHOMEINFO, (base) => {  return new Promise(async resolve => {    let data = await Http.get({      url: Apis.ls_url + Apis.allHomeInfo,      data: {}    })    resolve(data)**//返回到reduer的action.payload**  })})

用法

<script>  import wepy from &#39;wepy&#39;  import { connect } from &#39;wepy-redux&#39;  import { getAllHoomInfo } from &#39;../store/actions/base.js&#39;// 引入action方法  import { getStore } from &#39;wepy-redux&#39;   const store = getStore()    @connect({    data:(state) => state.base.data  })  export default class Index extends wepy.page {    data = {    }    computed = {    }    onLoad() {      store.dispatch(getAllHoomInfo(store.getState().base))    }      }</script>

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