Vue 核心技术与实战day07

1. vuex概述

2. 构建 vuex [多组件数据共享] 环境

<template><div id="app"><h1>根组件- {{ title }}- {{ count }}</h1><input :value="count" @input="handleInput" type="text"><Son1></Son1><hr><Son2></Son2></div>
</template><script>
import Son1 from './components/Son1.vue'
import Son2 from './components/Son2.vue'
import { mapState } from 'vuex'
// console.log(mapState(['count', 'title']))export default {name: 'app',created () {// console.log(this.$router) // 没配console.log(this.$store.state.count)},computed: {...mapState(['count', 'title'])},data: function () {return {}},methods: {handleInput (e) {// 1. 实时获取输入框的值const num = +e.target.value// 2. 提交mutation，调用mutation函数this.$store.commit('changeCount', num)}},components: {Son1,Son2}
}
</script><style>
#app {width: 600px;margin: 20px auto;border: 3px solid #ccc;border-radius: 3px;padding: 10px;
}
</style>

<template><div class="box"><h2>Son1 子组件</h2>从vuex中获取的值: <label>{{ $store.state.count }}</label><br><button @click="handleAdd(1)">值 + 1</button><button @click="handleAdd(5)">值 + 5</button><button @click="handleAdd(10)">值 + 10</button><button @click="handleChange">一秒后修改成666</button><button @click="changeFn">改标题</button><hr><!-- 计算属性getters --><div>{{ $store.state.list }}</div><div>{{ $store.getters.filterList }}</div><hr><!-- 测试访问模块中的state - 原生 --><div>{{ $store.state.user.userInfo.name }}</div><button @click="updateUser">更新个人信息</button><button @click="updateUser2">一秒后更新信息</button><div>{{ $store.state.setting.theme }}</div><button @click="updateTheme">更新主题色</button><hr><!-- 测试访问模块中的getters - 原生 --><div>{{ $store.getters['user/UpperCaseName'] }}</div></div>
</template><script>
export default {name: 'Son1Com',created () {console.log(this.$store.getters)},methods: {updateUser () {// $store.commit('模块名/mutation名', 额外传参)this.$store.commit('user/setUser', {name: 'xiaowang',age: 25})},updateUser2 () {// 调用action dispatchthis.$store.dispatch('user/setUserSecond', {name: 'xiaohong',age: 28})},updateTheme () {this.$store.commit('setting/setTheme', 'pink')},handleAdd (n) {// 错误代码(vue默认不会监测，监测需要成本)// this.$store.state.count++// console.log(this.$store.state.count)// 应该通过 mutation 核心概念，进行修改数据// 需要提交调用mutation// this.$store.commit('addCount')// console.log(n)// 调用带参数的mutation函数this.$store.commit('addCount', {count: n,msg: '哈哈'})},changeFn () {this.$store.commit('changeTitle', '传智教育')},handleChange () {// 调用action// this.$store.dispatch('action名字', 额外参数)this.$store.dispatch('changeCountAction', 666)}}
}
</script><style lang="css" scoped>
.box{border: 3px solid #ccc;width: 400px;padding: 10px;margin: 20px;
}
h2 {margin-top: 10px;
}
</style>

<template><div class="box"><h2>Son2 子组件</h2>从vuex中获取的值:<label>{{ count }}</label><br /><button @click="subCount(1)">值 - 1</button><button @click="subCount(5)">值 - 5</button><button @click="subCount(10)">值 - 10</button><button @click="changeCountAction(888)">1秒后改成888</button><button @click="changeTitle('前端程序员')">改标题</button><hr><div>{{ filterList }}</div><hr><!-- 访问模块中的state --><div>{{ user.userInfo.name }}</div><div>{{ setting.theme }}</div><hr><!-- 访问模块中的state --><div>user模块的数据：{{ userInfo }}</div><button @click="setUser({ name: 'xiaoli', age: 80 })">更新个人信息</button><button @click="setUserSecond({ name: 'xiaoli', age: 80 })">一秒后更新信息</button><div>setting模块的数据：{{ theme }} - {{ desc }}</div><button @click="setTheme('skyblue')">更新主题</button><hr><!-- 访问模块中的getters --><div>{{ UpperCaseName }}</div></div>
</template><script>
import { mapState, mapMutations, mapActions, mapGetters } from 'vuex'
export default {name: 'Son2Com',computed: {// mapState 和 mapGetters 都是映射属性...mapState(['count', 'user', 'setting']),...mapState('user', ['userInfo']),...mapState('setting', ['theme', 'desc']),...mapGetters(['filterList']),...mapGetters('user', ['UpperCaseName'])},methods: {// mapMutations 和 mapActions 都是映射方法// 全局级别的映射...mapMutations(['subCount', 'changeTitle']),...mapActions(['changeCountAction']),// 分模块的映射...mapMutations('setting', ['setTheme']),...mapMutations('user', ['setUser']),...mapActions('user', ['setUserSecond'])// handleSub (n) {//   this.subCount(n)// }}
}
</script><style lang="css" scoped>
.box {border: 3px solid #ccc;width: 400px;padding: 10px;margin: 20px;
}
h2 {margin-top: 10px;
}
</style>

3. 创建一个空仓库

     //这里面存放的就是vuex相关的核心代码import Vue from 'vue'import Vuex from 'vuex//插件安装Vue.use(Vuex)//创建仓库（空仓库）const store = new Vuex.Store()//到处给main.js使用export dafault store

导入挂载：

import Vue from 'vue'
import App from './App.vue'
import store from '@/store/index'
console.log(store.state.count)Vue.config.productionTip = falsenew Vue({render: h => h(App),store
}).$mount('#app')

验证是否导入成功

<template><div id="app"><h1>根组件- {{ title }}- {{ count }}</h1><input :value="count" @input="handleInput" type="text"><Son1></Son1><hr><Son2></Son2></div>
</template><script>
import Son1 from './components/Son1.vue'
import Son2 from './components/Son2.vue'
import { mapState } from 'vuex'
// console.log(mapState(['count', 'title']))export default {name: 'app',created () {// console.log(this.$router) // 没配console.log(this.$store.state.count)},computed: {...mapState(['count', 'title'])},data: function () {return {}},methods: {handleInput (e) {// 1. 实时获取输入框的值const num = +e.target.value// 2. 提交mutation，调用mutation函数this.$store.commit('changeCount', num)}},components: {Son1,Son2}
}
</script><style>
#app {width: 600px;margin: 20px auto;border: 3px solid #ccc;border-radius: 3px;padding: 10px;
}
</style>

4. 核心概念 - state 状态

// 这里面存放的就是 vuex 相关的核心代码
import Vue from 'vue'
import Vuex from 'vuex'
import user from './modules/user'
import setting from './modules/setting'// 插件安装
Vue.use(Vuex)// 创建仓库
const store = new Vuex.Store({// 严格模式 (有利于初学者，检测不规范的代码 => 上线时需要关闭)strict: true,// 1. 通过 state 可以提供数据 (所有组件共享的数据)state: {title: '仓库大标题',count: 100,list: [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]},// 2. 通过 mutations 可以提供修改数据的方法mutations: {// 所有mutation函数，第一个参数，都是 state// 注意点：mutation参数有且只能有一个，如果需要多个参数，包装成一个对象addCount (state, obj) {console.log(obj)// 修改数据state.count += obj.count},subCount (state, n) {state.count -= n},changeCount (state, newCount) {state.count = newCount},changeTitle (state, newTitle) {state.title = newTitle}},// 3. actions 处理异步// 注意：不能直接操作 state，操作 state，还是需要 commit mutationactions: {// context 上下文 (此处未分模块，可以当成store仓库)// context.commit('mutation名字', 额外参数)changeCountAction (context, num) {// 这里是setTimeout模拟异步，以后大部分场景是发请求setTimeout(() => {context.commit('changeCount', num)}, 1000)}},// 4. getters 类似于计算属性getters: {// 注意点：// 1. 形参第一个参数，就是state// 2. 必须有返回值，返回值就是getters的值filterList (state) {return state.list.filter(item => item > 5)}},// 5. modules 模块modules: {user,setting}
})// 导出给main.js使用
export default store

<template><div id="app"><h1>根组件- {{ $store.state.title }}- {{  $store.state.count }}</h1><input :value="count" @input="handleInput" type="text"><Son1></Son1><hr><Son2></Son2></div>
</template><script>
import Son1 from './components/Son1.vue'
import Son2 from './components/Son2.vue'
import { mapState } from 'vuex'
// console.log(mapState(['count', 'title']))export default {name: 'app',created () {// console.log(this.$router) // 没配console.log(this.$store.state.count)},computed: {...mapState(['count', 'title'])},data: function () {return {}},methods: {handleInput (e) {// 1. 实时获取输入框的值const num = +e.target.value// 2. 提交mutation，调用mutation函数this.$store.commit('changeCount', num)}},components: {Son1,Son2}
}
</script><style>
#app {width: 600px;margin: 20px auto;border: 3px solid #ccc;border-radius: 3px;padding: 10px;
}
</style>

5. 核心概念 - mutations

第一：

第二：·

第三

如果说要同时传递好几个参数，可以包装成一个对象

6. 核心概念 - mutations - 练习

练习1：

练习2：

<template><div id="app"><h1>根组件- {{ title }}- {{ count }}</h1>//1<input :value="count" @input="handleInput" type="text"><Son1></Son1><hr><Son2></Son2></div>
</template><script>
import Son1 from './components/Son1.vue'
import Son2 from './components/Son2.vue'
import { mapState } from 'vuex'
// console.log(mapState(['count', 'title']))export default {name: 'app',created () {// console.log(this.$router) // 没配console.log(this.$store.state.count)},computed: {...mapState(['count', 'title'])},data: function () {return {}},//2methods: {handleInput (e) {// 1. 实时获取输入框的值const num = +e.target.value//4// 2. 提交mutation，调用mutation函数this.$store.commit('changeCount', num)}},components: {Son1,Son2}
}
</script><style>
#app {width: 600px;margin: 20px auto;border: 3px solid #ccc;border-radius: 3px;padding: 10px;
}
</style>

7. 辅助函数 - mapMutations

8. 核心概念 - actions

9. 辅助函数 - mapActions

调用这个

10. 核心概念 - getters

<template><div class="box"><h2>Son2 子组件</h2>从vuex中获取的值:<label>{{ count }}</label><br /><button @click="subCount(1)">值 - 1</button><button @click="subCount(5)">值 - 5</button><button @click="subCount(10)">值 - 10</button><button @click="changeCountAction(888)">1秒后改成888</button><button @click="changeTitle('前端程序员')">改标题</button><hr><div>{{ filterList }}</div><hr><!-- 访问模块中的state --><div>{{ user.userInfo.name }}</div><div>{{ setting.theme }}</div><hr><!-- 访问模块中的state --><div>user模块的数据：{{ userInfo }}</div><button @click="setUser({ name: 'xiaoli', age: 80 })">更新个人信息</button><button @click="setUserSecond({ name: 'xiaoli', age: 80 })">一秒后更新信息</button><div>setting模块的数据：{{ theme }} - {{ desc }}</div><button @click="setTheme('skyblue')">更新主题</button><hr><!-- 访问模块中的getters --><div>{{ UpperCaseName }}</div></div>
</template><script>
import { mapState, mapMutations, mapActions, mapGetters } from 'vuex'
export default {name: 'Son2Com',computed: {// mapState 和 mapGetters 都是映射属性...mapState(['count', 'user', 'setting']),...mapState('user', ['userInfo']),...mapState('setting', ['theme', 'desc']),...mapGetters(['filterList']),...mapGetters('user', ['UpperCaseName'])},methods: {// mapMutations 和 mapActions 都是映射方法// 全局级别的映射...mapMutations(['subCount', 'changeTitle']),...mapActions(['changeCountAction']),// 分模块的映射...mapMutations('setting', ['setTheme']),...mapMutations('user', ['setUser']),...mapActions('user', ['setUserSecond'])// handleSub (n) {//   this.subCount(n)// }}
}
</script><style lang="css" scoped>
.box {border: 3px solid #ccc;width: 400px;padding: 10px;margin: 20px;
}
h2 {margin-top: 10px;
}
</style>

11. 核心概念 - 模块 module (进阶语法)

第一：

// user模块
const state = {userInfo: {name: 'zs',age: 18},score: 80
}
const mutations = {setUser (state, newUserInfo) {state.userInfo = newUserInfo}
}
const actions = {setUserSecond (context, newUserInfo) {// 将异步在action中进行封装setTimeout(() => {// 调用mutation   context上下文，默认提交的就是自己模块的action和mutationcontext.commit('setUser', newUserInfo)}, 1000)}
}
const getters = {// 分模块后，state指代子模块的stateUpperCaseName (state) {return state.userInfo.name.toUpperCase()}
}export default {namespaced: true,state,mutations,actions,getters
}

// setting模块
const state = {theme: 'light', // 主题色desc: '测试demo'
}
const mutations = {setTheme (state, newTheme) {state.theme = newTheme}
}
const actions = {}
const getters = {}export default {namespaced: true,state,mutations,actions,getters
}

第二：

法一：

法二：

第三

法一：

法2：

第四

法一：

法2：

第五

法一：

法二

12. 综合案例 - 购物车

1.

2

3

4

存储数据

渲染

<template><div class="app-container"><!-- Header 区域 --><cart-header></cart-header><!-- 商品 Item 项组件 --><cart-item v-for="item in list" :key="item.id" :item="item"></cart-item><!-- Foote 区域 --><cart-footer></cart-footer></div>
</template><script>
import CartHeader from '@/components/cart-header.vue'
import CartFooter from '@/components/cart-footer.vue'
import CartItem from '@/components/cart-item.vue'import { mapState } from 'vuex'export default {name: 'App',created () {this.$store.dispatch('cart/getList')},computed: {...mapState('cart', ['list'])},components: {CartHeader,CartFooter,CartItem}
}
</script><style lang="less" scoped>
.app-container {padding: 50px 0;font-size: 14px;
}
</style>

<template><div class="goods-container"><!-- 左侧图片区域 --><div class="left"><img :src="item.thumb" class="avatar" alt=""></div><!-- 右侧商品区域 --><div class="right"><!-- 标题 --><div class="title">{{ item.name }}</div><div class="info"><!-- 单价 --><span class="price">￥{{ item.price }}</span><div class="btns"><!-- 按钮区域 --><button class="btn btn-light" @click="btnClick(-1)">-</button><span class="count">{{ item.count }}</span><button class="btn btn-light" @click="btnClick(1)">+</button></div></div></div></div>
</template><script>
export default {name: 'CartItem',methods: {btnClick (step) {const newCount = this.item.count + stepconst id = this.item.idif (newCount < 1) returnthis.$store.dispatch('cart/updateCountAsync', {id,newCount})}},//直接接收props: {item: {type: Object,required: true}}
}
</script><style lang="less" scoped>
.goods-container {display: flex;padding: 10px;+ .goods-container {border-top: 1px solid #f8f8f8;}.left {.avatar {width: 100px;height: 100px;}margin-right: 10px;}.right {display: flex;flex-direction: column;justify-content: space-between;flex: 1;.title {font-weight: bold;}.info {display: flex;justify-content: space-between;align-items: center;.price {color: red;font-weight: bold;}.btns {.count {display: inline-block;width: 30px;text-align: center;}}}}
}.custom-control-label::before,
.custom-control-label::after {top: 3.6rem;
}
</style>

5

<template><div class="goods-container"><!-- 左侧图片区域 --><div class="left"><img :src="item.thumb" class="avatar" alt=""></div><!-- 右侧商品区域 --><div class="right"><!-- 标题 --><div class="title">{{ item.name }}</div><div class="info"><!-- 单价 --><span class="price">￥{{ item.price }}</span><div class="btns"><!-- 按钮区域 --><button class="btn btn-light" @click="btnClick(-1)">-</button><span class="count">{{ item.count }}</span><button class="btn btn-light" @click="btnClick(1)">+</button></div></div></div></div>
</template><script>
export default {name: 'CartItem',methods: {btnClick (step) {const newCount = this.item.count + stepconst id = this.item.idif (newCount < 1) return
//调用this.$store.dispatch('cart/updateCountAsync', {id,newCount})}},props: {item: {type: Object,required: true}}
}
</script><style lang="less" scoped>
.goods-container {display: flex;padding: 10px;+ .goods-container {border-top: 1px solid #f8f8f8;}.left {.avatar {width: 100px;height: 100px;}margin-right: 10px;}.right {display: flex;flex-direction: column;justify-content: space-between;flex: 1;.title {font-weight: bold;}.info {display: flex;justify-content: space-between;align-items: center;.price {color: red;font-weight: bold;}.btns {.count {display: inline-block;width: 30px;text-align: center;}}}}
}.custom-control-label::before,
.custom-control-label::after {top: 3.6rem;
}
</style>

import axios from 'axios'
export default {namespaced: true,state () {return {// 购物车数据 [{}, {}]list: []}},mutations: {updateList (state, newList) {state.list = newList},// obj: { id: xxx, newCount: xxx }updateCount (state, obj) {// 根据 id 找到对应的对象，更新count属性即可const goods = state.list.find(item => item.id === obj.id)goods.count = obj.newCount}},actions: {// 请求方式：get// 请求地址：http://localhost:3000/cartasync getList (context) {const res = await axios.get('http://localhost:3000/cart')context.commit('updateList', res.data)},// 请求方式：patch// 请求地址：http://localhost:3000/cart/:id值  表示修改的是哪个对象// 请求参数：// {//   name: '新值',  【可选】//   price: '新值', 【可选】//   count: '新值', 【可选】//   thumb: '新值'  【可选】// }async updateCountAsync (context, obj) {// 将修改更新同步到后台服务器await axios.patch(`http://localhost:3000/cart/${obj.id}`, {//count不能改count: obj.newCount})// 将修改更新同步到 vuexcontext.commit('updateCount', {id: obj.id,newCount: obj.newCount})}},getters: {// 商品总数量 累加counttotal (state) {return state.list.reduce((sum, item) => sum + item.count, 0)},// 商品总价格 累加count * pricetotalPrice (state) {return state.list.reduce((sum, item) => sum + item.count * item.price, 0)}}
}

6