vue--day51----todolist 中App.vue 和 MyItem.vue 类似 父亲和子通信 通过全局事件总线实现通信

标签：vue -- App 通信 li todo id todos

1.mainjs

/** * 该文件是整个项目的入口文件 */ //引入Vue import Vue from 'vue' // 引入App 组件 他是所有组件的父组件 import App from './App.vue'
//关闭vue 的生产提示 Vue.config.productionTip = false // const Demo=Vue.extend({}) // const d=new Demo(); // Vue.prototype.x=d; // 创建Vue 实例对象--vm new Vue({ //将 app 组件放入到容器中 render: h => h(App),
beforeCreate(){ Vue.prototype.$bus=this // 安装全局事件总监 } }).$mount('#app') 2. App.vue
<template> <div id="root"> <div class="todo-container"> <div class="todo-wrap"> <!-- @addTodo 事件名 addTodo 回调名--> <MyHeader @addTodo="addTodo"/> <!--父亲给儿子传数据 父亲通过数据绑定传数据 儿子通过 props:['todos'],//声明接收todo 对象 --> <MyList :todos="todos" :checkTodo="checkTodo" :deleteTodo="deleteTodo"/> <MyFooter :todos="todos" @checkAllTodo="checkAllTodo" @clearAllTodo="clearAllTodo"/> </div> </div> </div>     </template>   <script> //样式的引入和这里有关系 import MyHeader from './components/MyHeader.vue'; import MyList from './components/MyList.vue'; import MyFooter from './components/MyFooter.vue';     export default { name: 'App', components: { MyHeader, MyList, MyFooter }, data(){ return { todos:JSON.parse(localStorage.getItem("todos"))||[] }   },   methods:{ // 添加一个todo addTodo(todoObj){ // console.log('我是app组件,我收到了数据x==',todoObj); this.todos.unshift(todoObj)   }, //勾选or 取消勾选 todo checkTodo(id){ this.todos.forEach((todo)=>{ if(todo.id===id) todo.done=!todo.done }) }, //删除一个todo deleteTodo(id){ this.todos=this.todos.filter((todo)=>{ return todo.id!==id; }) },   //全选or全不选 checkAllTodo(done){ this.todos.forEach((todo)=>{ todo.done=done }) },   clearAllTodo(){ this.todos=this.todos.filter((todo)=>{ return !todo.done }) }   }, watch:{ // todos(value){ // localStorage.setItem("todos", JSON.stringify(value)); // } todos:{ deep:true, handler(value){ localStorage.setItem("todos", JSON.stringify(value)); } }   }, mounted(){ this.$bus.$on('checkTodo',this.checkTodo) this.$bus.$on('deleteTodo',this.deleteTodo) }, beforeDestroy(){ this.$bus.$off('checkTodo') this.$bus.$off('deleteTodo') } } </script>   <style>     /* 整体样式 */ body { background: rgba(230, 241, 245, 0.816); }   .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; }   .todo-container { width: 600px; margin: 0 auto; }   .todo-container .todo-wrap { padding: 10px; border: 1px solid #ddd; border-radius: 5px; }   </style>  3. MyItem.vue   <template> <li> <label> <input type="checkbox" :checked="todo.done" @click="handlerCheck(todo.id)"/>
<!--
let a=1; a=2; 改了 let obj={a:1,b:2} obj.a=8; 代码层底改了 但是 obj 内存地址没有变化 vue 认为没有变化 如下代码也能实现功能 但是步太推荐 因为有点违反了原则 因为修改了 props 属性 --> <!-- <input type="checkbox" v-model:="todo.done"/> -->
  <span>{{todo.title}}</span> </label> <button class="btn btn-danger" @click="hadnlerDelete(todo.id)">删除</button> </li> </template>
<script> export default { name:"MyItem", props:['todo'],//声明接收todo 对象 mounted(){ //console.log(this.todo); }, methods:{ //勾选或者取消勾选 handlerCheck(id){ //通知app 组件 将对应的todo 对象的done 值取反 //console.log("id",id); //this.checkTodo(id);
this.$bus.$emit('checkTodo',id) }, //闪促 hadnlerDelete(id){ if(confirm('确定删除么')){ //console.log("id",id);
//通知app 删除一个对象 this.deleteTodo(id);

this.$bus.$emit('deleteTodo',id) } } } } </script>
<style scoped>
/*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:hover { background-color: grey; 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:hover button { display: block; }
li:before { content: initial; }
li:last-child { border-bottom: none; }
</style>

   

标签：vue,--,App,通信,li,todo,id,todos
From： https://www.cnblogs.com/satisfysmy/p/17604804.html