Vue50 todolist自定义事件版本

代码

MyFooter.vue

<template><div class="todo-footer" v-show="total"><label><!-- <input type="checkbox" :checked="isAll" @change="checkAll"/> --><input type="checkbox" v-model="isAll"/></label><span><span>已完成{{doneTotal}}</span> / 全部{{total}}</span><button class="btn btn-danger" @click="clearAll">清除已完成任务</button></div>
</template><script>export default {name:'MyFooter',props:['todos'],computed: {//总数total(){return this.todos.length},//已完成数doneTotal(){//此处使用reduce方法做条件统计/* const x = this.todos.reduce((pre,current)=>{console.log('@',pre,current)return pre + (current.done ? 1 : 0)},0) *///简写return this.todos.reduce((pre,todo)=> pre + (todo.done ? 1 : 0) ,0)},//控制全选框isAll:{//全选框是否勾选get(){return this.doneTotal === this.total && this.total > 0},//isAll被修改时set被调用set(value){// this.checkAllTodo(value)this.$emit('checkAllTodo',value)}}},methods: {/* checkAll(e){this.checkAllTodo(e.target.checked)} *///清空所有已完成clearAll(){// this.clearAllTodo()this.$emit('clearAllTodo')}},}
</script><style scoped>/*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>

MyHeader.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" v-model="title" @keyup.enter="add"/></div>
</template><script>import {nanoid} from 'nanoid'export default {name:'MyHeader',data() {return {//收集用户输入的titletitle:''}},methods: {add(){//校验数据if(!this.title.trim()) return alert('输入不能为空')//将用户的输入包装成一个todo对象const todoObj = {id:nanoid(),title:this.title,done:false}//通知App组件去添加一个todo对象this.$emit('addTodo',todoObj,1,2,3)//清空输入this.title = ''}},}
</script><style scoped>/*header*/.todo-header input {width: 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>

MyItem.vue

<template><li><label><input type="checkbox" :checked="todo.done" @change="handleCheck(todo.id)"/><!-- 如下代码也能实现功能，但是不太推荐，因为有点违反原则，因为修改了props --><!-- <input type="checkbox" v-model="todo.done"/> --><span>{{todo.title}}</span></label><button class="btn btn-danger" @click="handleDelete(todo.id)">删除</button></li>
</template><script>export default {name:'MyItem',//声明接收todo、checkTodo、deleteTodoprops:['todo','checkTodo','deleteTodo'],methods: {//勾选or取消勾选handleCheck(id){//通知App组件将对应的todo对象的done值取反this.checkTodo(id)},//删除handleDelete(id){if(confirm('确定删除吗？')){//通知App组件将对应的todo对象删除this.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 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;}li:hover{background-color: #ddd;}li:hover button{display: block;}
</style>

MyList.vue

<template><ul class="todo-main"><MyItem v-for="todoObj in todos":key="todoObj.id" :todo="todoObj" :checkTodo="checkTodo":deleteTodo="deleteTodo"/></ul>
</template><script>import MyItem from './MyItem'export default {name:'MyList',components:{MyItem},//声明接收App传递过来的数据，其中todos是自己用的，checkTodo和deleteTodo是给子组件MyItem用的props:['todos','checkTodo','deleteTodo']}
</script><style scoped>/*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>

App.vue

<template><div id="root"><div class="todo-container"><div class="todo-wrap"><MyHeader @addTodo="addTodo"/><MyList :todos="todos" :checkTodo="checkTodo" :deleteTodo="deleteTodo"/><MyFooter :todos="todos" @checkAllTodo="checkAllTodo" @clearAllTodo="clearAllTodo"/></div></div></div>
</template><script>import MyHeader from './components/MyHeader'import MyList from './components/MyList'import MyFooter from './components/MyFooter.vue'export default {name:'App',components:{MyHeader,MyList,MyFooter},data() {return {//由于todos是MyHeader组件和MyFooter组件都在使用，所以放在App中（状态提升）todos:JSON.parse(localStorage.getItem('todos')) || []}},methods: {//添加一个todoaddTodo(todoObj){this.todos.unshift(todoObj)},//勾选or取消勾选一个todocheckTodo(id){this.todos.forEach((todo)=>{if(todo.id === id) todo.done = !todo.done})},//删除一个tododeleteTodo(id){this.todos = this.todos.filter( todo => todo.id !== id )},//全选or取消全选checkAllTodo(done){this.todos.forEach((todo)=>{todo.done = done})},//清除所有已经完成的todoclearAllTodo(){this.todos = this.todos.filter((todo)=>{return !todo.done})}},watch: {todos:{deep:true,handler(value){localStorage.setItem('todos',JSON.stringify(value))}}},}
</script><style>/*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;}.todo-container {width: 600px;margin: 0 auto;}.todo-container .todo-wrap {padding: 10px;border: 1px solid #ddd;border-radius: 5px;}
</style>

运行