• vue vuex应用


    vue结构图:

    vuex为vue的一个插件,用来管理共享数据的,局部数据声明在自己组件内部.
    没有使用vuex时,所有共享数据和操作数据的方法都声明在父组件内,数据的通信用props及pubsub等.下面是由vuex改下之前编写的一个小demo:

    效果图示:
    在这里插入图片描述

    需求:
    header部输入任务,进行添加,在list中显示;
    list中每个item项,鼠标移入时,背景变灰并显示delete按钮.点击按钮可删除该项;鼠标移出时,恢复原样;
    footer部: 1.根据列表勾选状态及数量显示已完成数和全部数; 2.当已完成数为0时,不显示清除已完成任务按钮; 3.当已完成数等于全部数量时,全选框勾选. 4.当list列表为空时,全选框不勾选; 5.当主动勾选全选时,所有项都勾选,去勾选时所有项去勾选.

    项目目录:
    在这里插入图片描述
    代码:

    1.main.js

    import Vue from 'vue'
    import App from './App'
    import store from './store'
    
    import './base.css' // 全局引入base.css文件
    
    /*new Vue({
      el: '#app',
      components: { App },
      template: '<App/>',
      store // 全局注册store对象
    })*/
    
    new Vue({
      el: '#app',
      render: h => h(App),
      store // 全局注册store对象
    })
    
    /*new vue({
      el: '#app',
      render: function (createElement) {
        return createElement(App)   // <App/>
      },
      store
    })*/
    
    

    2.App.vue

    <template>
      <div class="todo-container">
        <div class="todo-wrap">
          <!-- 传递函数属性(传递性)和绑定事件监听(用于父子组件) -->
          <Header />  <!-- 给标签对象绑定addProject事件监听 -->
          <List />
          <todo-footer />
        </div>
      </div>
    </template>
    
    <script>
      import Header from './components/Header'
      import List from './components/List'
      import TodoFooter from './components/Footer'
    
      export default {
        name: 'App',
        mounted() {
          // 异步获取projects数据并显示: 发送命令给actions
          this.$store.dispatch('reqProjects')
        },
        components: { Header, List, TodoFooter},
    
      }
    </script>
    
    <style>
      /*app*/
      .todo-container {
         600px;
        margin: 0 auto;
      }
      .todo-container .todo-wrap {
        padding: 10px;
        border: 1px solid #ddd;
        border-radius: 5px;
      }
    </style>
    
    

    3.Head.vue

    <template>
      <div class="todo-header">
        <input type="text" placeholder="请输入你的任务名称,按回车键确认"
          @keyup.enter="addItem" v-model="content"/>
      </div>
    </template>
    
    <script>
        export default {
          props: {
            // addProject: Function
          },
          data () {
            return {
              content: '',  // 组件内部使用的状态,不存在共享的问题 --> 不需要使用vuex管理
            }
          },
          methods: {
            addItem () {
              // 1.检查输入的合法性
              const content = this.content.trim()
              if (!content) { // content默认不为空字符串,可不写 === ''
                alert("不能为空")
                return
              }
              // 2.根据输入生成一个project对象
              const project = {
                content: this.content,
                complete: false
              }
              // 3.将对象添加到projects中
              // this.addProject(project)
              // 触发自定义事件:addProject; 只能用在父子组件,不能跨代通信
              // this.$emit('addProject',project)
              this.$store.dispatch('addProject', project)
              // 4.清空输入
              this.content = ''
            }
          }
        }
    </script>
    
    <style>
      /*header*/
      .todo-header input {
         560px;
        height: 28px;
        font-size: 14px;
        border: 1px solid #ccc;
        border-radius: 4px;
        padding: 4px 7px;
      }
    
      .todo-header input:focus {
        outline: none;
        border-color: rgba(82, 168, 236, 0.8);
        box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 8px rgba(82, 168, 236, 0.6);
      }
    
    </style>
    
    

    4.List.vue

    <template>
      <ul class="todo-main">
        <Item v-for="(project,index) in projects" :key="index" :project="project"
          :index="index" />
      </ul>
    </template>
    
    <script>
        import Item from "../components/Item";
        import {mapState} from 'vuex'
        import storageUtil from '../utils/storageUtil'
    
        export default {
          name: 'List',
          computed: {
            ...mapState(['projects'])
          },
          watch: {  // 监视
            projects: {
              deep: true, // 深度监视
              /*handler: function (val) {
                // 将projects最新的值的json数据保存到localStorage
                // window.localStorage.setItem('project_key', JSON.stringify(val))
                storageUtil.saveProjects(val)
              }*/
              handler: storageUtil.saveProjects
            }
          },
          components: {Item},
        }
    </script>
    
    <style>
      /*main*/
      .todo-main {
        margin-left: 0px;
        border: 1px solid #ddd;
        border-radius: 2px;
        padding: 0px;
      }
    
      .todo-empty {
        height: 40px;
        line-height: 40px;
        border: 1px solid #ddd;
        border-radius: 2px;
        padding-left: 5px;
        margin-top: 10px;
      }
    </style>
    
    

    5.Item.vue

    <template>
    <!-- onmouseover="" onmouseout="" -->
      <li @mouseenter="handleEnter(true)" @mouseleave="handleEnter(false)" :style="{background: bgColor}">
        <label>
          <input type="checkbox" v-model="project.complete"/>
          <span>{{project.content}}</span>
        </label>
        <button class="btn btn-danger" v-show="isShow" @click="deleteItem">删除</button>
      </li>
    </template>
    
    <script>
        export default {
          name: 'Item',
          props: {
            project: Object,
            index: Number,
          },
          data () {
            return {
              bgColor: 'white',
              isShow: false
            }
          },
          methods: {
            handleEnter (isEnter) {
              if (isEnter) {
                this.bgColor = '#aaaaaa'
                this.isShow = true
              }else {
                this.bgColor = 'white'
                this.isShow = false
              }
            },
            deleteItem () {
              const {project, index} = this
              if (window.confirm(`确认删除${project.content}吗`)) {
                this.$store.dispatch('deleteProject',index)
              }
            }
          }
        }
    </script>
    
    <style>
      /*item*/
      li {
        list-style: none;
        height: 36px;
        line-height: 36px;
        padding: 0 5px;
        border-bottom: 1px solid #ddd;
      }
    
      li label {
        float: left;
        cursor: pointer;
      }
    
      li label li input {
        vertical-align: middle;
        margin-right: 6px;
        position: relative;
        top: -1px;
      }
    
      li button {
        float: right;
        display: none;
        margin-top: 3px;
      }
    
      li:before {
        content: initial;
      }
    
      li:last-child {
        border-bottom: none;
      }
    </style>
    
    

    6.Footer.vue

    <template>
      <div class="todo-footer">
        <label>
          <input type="checkbox" v-model="isAllCheck"/>
        </label>
        <span>
              <span>已完成{{completeSize}}</span> / 全部{{totalSize}}
            </span>
        <button class="btn btn-danger" v-show="completeSize" @click="deleteAllComplete">清除已完成任务</button>
      </div>
    </template>
    
    <script>
      import {mapGetters,mapActions} from 'vuex'
    
      export default {
        name: 'Footer',
        computed: {
          ...mapGetters(['completeSize','totalSize']),
    
          isAllCheck: {
            get () {  //获取多选框的值,当已完成数等于全部数量且已完成数大于0时,勾选(默认>0,可以不写)
              return this.$store.getters.isAllSelect
            },
            set (value) { //监视多选框的值,value是当前多选框最新的值
              this.$store.dispatch('setSelect',value)
            }
          }
        },
        methods: {
          ...mapActions(['deleteAllComplete'])
        }
      }
    </script>
    
    <style>
      /*footer*/
      .todo-footer {
        height: 40px;
        line-height: 40px;
        padding-left: 6px;
        margin-top: 5px;
      }
    
      .todo-footer label {
        display: inline-block;
        margin-right: 20px;
        cursor: pointer;
      }
    
      .todo-footer label input {
        position: relative;
        top: -1px;
        vertical-align: middle;
        margin-right: 5px;
      }
    
      .todo-footer button {
        float: right;
        margin-top: 5px;
      }
    </style>
    
    

    7.index.js

    /**
     * vuex最核心的管理对象store
     */
    import Vue from 'vue'
    import Vuex from 'vuex'
    import state from './state'
    import mutations from './Mutations'
    import actions from './Actions'
    import getters from './getters'
    
    Vue.use(Vuex)
    
    export default new Vuex.Store({
      state,
      mutations,
      actions,
      getters
    })
    
    

    8.actives.js

    /**
     * 包含n个用于间接更新状态的方法的对象模块
     */
    import {ADD_PROJECT, DEL_PROJECT, SELECT_ALL_PROJECT, DELETE_COMPLETE_PROJECT, RECEIVE_PROJECTS} from './mutations-types'
    import storageUtil from '../utils/storageUtil'
    
    export default {
      addProject( {commit}, project){ //添加project
        // 提交对mutations的请求
        commit(ADD_PROJECT, project)
      },
      deleteProject( {commit}, index){  //根据index删除project
        // 提交对mutations的请求
        commit(DEL_PROJECT, index)
      },
      setSelect ({commit}, check) { //根据全选框值设置多选框是否勾选
        commit(SELECT_ALL_PROJECT, check)
      },
      deleteAllComplete ({commit}) {  //删除所有完成的任务
        commit(DELETE_COMPLETE_PROJECT)
      },
      reqProjects({commit}) { // 异步获取projects并更新状态
        // 模拟
        setTimeout(() => {
          // 读取数据
          const projects = storageUtil.readProjects()
          // 提交
          commit('receive_projects', projects)
        },1000)
      }
    
    }
    
    

    9.mutations-types.js

    /**
     * 所有mutations的名称常量
     * @type {string}
     */
    export const ADD_PROJECT = 'add_project'  // 添加project
    export const DEL_PROJECT = 'del_project'  // 删除project
    export const SELECT_ALL_PROJECT = 'select_all_project'  // 全选/全不选projects
    export const DELETE_COMPLETE_PROJECT = 'delete_complete_project' // 删除所有选中的
    export const RECEIVE_PROJECTS = 'receive_projects' // 接受projects
    
    

    10.mutations.js

    /**
     * 包含n个用于直接更新状态的方法的对象模块
     */
    import {ADD_PROJECT, DEL_PROJECT, SELECT_ALL_PROJECT, DELETE_COMPLETE_PROJECT, RECEIVE_PROJECTS} from './mutations-types'
    
    export default {
      [ADD_PROJECT](state, project) { // 将常量转为变量用 []
        state.projects.unshift(project)
      },
      [DEL_PROJECT](state, index) {
        state.projects.splice(index, 1)
      },
      [SELECT_ALL_PROJECT](state, check) {
        //根据全选框值设置多选框是否勾选
        state.projects.forEach(project => project.complete = check)
      },
      [DELETE_COMPLETE_PROJECT](state) {
        //将project中complete为true的过滤掉,留下false为一个新的数组,重新赋值
        state.projects = state.projects.filter(project => !project.complete)
      },
      [RECEIVE_PROJECTS](state, projects) {
        state.projects = projects
      }
    
    }
    
    

    11.state.js

    /**
     * 状态对象模块
     */
    export default {
      // 从localStorage中读取数据
      projects: []
    }
    
    

    12.getters.js

    /**
     * 包含n个基于state的getter计算属性方法的对象模块
     */
    export default {
      // 完成的数量
      completeSize (state) {
        // 遍历projects,初始化preTotal为0,若project.complete为true则加1,返回最终preTotal值
        return state.projects.reduce((preTotal, project) => preTotal + (project.complete ? 1 : 0), 0)
      },
      // 总数量
      totalSize (state) {
        return state.projects.length
      },
      // 判断是否需要全选
      isAllSelect (state, getters) {  // 用this获取不到当前对象方法,用getters
        return getters.completeSize === getters.totalSize && getters.completeSize
      }
    }
    
    

    13.storageUtil.js

    /**
     * 使用localStorage存储数据的工具模块
     * 1.函数
     * 2.模块
     * 需要向外暴露一个功能还是多个功能
     */
    
    const PROJECTS_KEY = 'project_key'
    
    export default {
      saveProjects(val) {
        window.localStorage.setItem(PROJECTS_KEY, JSON.stringify(val))
    
      },
    
      readProjects() {
        return JSON.parse(window.localStorage.getItem(PROJECTS_KEY) || '[]');
      }
    }
    
    

    14.base.css

    /*base*/
    body {
      background: #fff;
    }
    
    .btn {
      display: inline-block;
      padding: 4px 12px;
      margin-bottom: 0;
      font-size: 14px;
      line-height: 20px;
      text-align: center;
      vertical-align: middle;
      cursor: pointer;
      box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.2), 0 1px 2px rgba(0, 0, 0, 0.05);
      border-radius: 4px;
    }
    
    .btn-danger {
      color: #fff;
      background-color: #da4f49;
      border: 1px solid #bd362f;
    }
    
    .btn-danger:hover {
      color: #fff;
      background-color: #bd362f;
    }
    
    .btn:focus {
      outline: none;
    }
    
    

    15.index.html

    <!DOCTYPE html>
    <html>
    <head>
      <meta charset="utf-8">
      <meta name="viewport" content="width=device-width,initial-scale=1.0">
      <title>vuex_demo</title>
      <link rel="stylesheet" href="./static/css/bootstrap.css">
      <style>
        .router-link-active {
          color: red !important;
        }
      </style>
    </head>
    <body>
    <div id="app"></div>
    <!-- built files will be auto injected -->
    </body>
    </html>
    
    
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  • 原文地址:https://www.cnblogs.com/itzlg/p/11925533.html
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