import TodoList from "./components/todoList";

export default {
 name: 'app',
 components: {
  TodoList
 }
}

<template>
 <div id="app">
  <h1>TO DO LIST !</h1>
  <todo-list></todo-list>
 </div>
</template>

data () {
   return{
     items:[
      {
        label:"homework",
        finish:false
      },
      {
        label:"run",
        finish:false
      },
      {
        label:"drink water",
        finish:false
      }
     ]
   }
 }

<ul>
  <li v-for="item in items">{{item.label}}</li>
</ul>

<ul>
  <li v-for="item in items" v-on:click="done(item)" v-bind:class="{done:item.finish}">{{item.label}}</li>
</ul>

methods:{
  done:function (item) {
    item.finish = !item.finish
  }
 }

.done{
  color: red;
 }