vue.jstodolist如何实现

const STORAGE_KEY = 'todos-vue.js'
export default{
 fetch(){
 return JSON.parse(window.localStorage.getItem(STORAGE_KEY) || '[]')
 },
 save(items){
 window.localStorage.setItem(STORAGE_KEY,JSON.stringify(items));
 }
}

<template>
 <p id="app">
 <h1 v-text="title"></h1>
 <input v-model="newItem" v-on:keyup.enter="addNew"/>
 <ul>
 <li v-for="item in items" v-bind:class="{finished:item.isFinished}" v-on:click='toogleFinish(item)'>
 {{item.label}}
 </li>
 </ul>
 </p>
</template>
<script>
import Store from './store'
export default {
 name: 'app',
 data () {
 return {
 title: 'this is a todo list',
 items:Store.fetch(),
 newItem:''
 }
 },
 watch:{
 items:{
 handler(items){ //经过变化的数组会作为第一个参数传入
 Store.save(items)
 console.log(Store.fetch());
 },
 deep:true //深度复制
 }
 },
 methods:{
 toogleFinish(item){
 item.isFinished = !item.isFinished
 },
 addNew(){
 this.items.push({
 label:this.newItem,
 isFinished:false,
 })
 this.newItem = ''
 }
 }
}
</script>
<style>
#app {
 font-family: 'Avenir', Helvetica, Arial, sans-serif;
 -webkit-font-smoothing: antialiased;
 -moz-osx-font-smoothing: grayscale;
 text-align: center;
 color: #2c3e50;
 margin-top: 60px;
}
.finished{
 text-decoration: underline;
}
</style>