Vue

HTML

<div id="app">
  <div class="block">
    <div class="text">{{ computedCounter }}</div>
    <div class="text">{{ methodsCounter() }}</div>
    <button @click="count += 1">カウントアップ (+1)</button>
  </div>

  <hr>

  <h2>Todos:</h2>
  <ol>
    <li v-for="todo in todos">
      <label>
        <input type="checkbox"
          v-on:change="toggle(todo)"
          v-bind:checked="todo.done">

        <del v-if="todo.done">
          {{ todo.text }}
        </del>
        <span v-else>
          {{ todo.text }}
        </span>
      </label>
    </li>
  </ol>
</div>

CSS

body {
  background: #20262E;
  padding: 20px;
  font-family: Helvetica;
}

#app {
  background: #fff;
  border-radius: 4px;
  padding: 20px;
  transition: all 0.2s;
}

li {
  margin: 8px 0;
}

h2 {
  font-weight: bold;
  margin-bottom: 15px;
}

del {
  color: rgba(0, 0, 0, 0.3);
}

.text {
  margin-bottom: 10px;
}

.block {
  margin: 10px auto;
}

Vue

new Vue({
  el: "#app",
  data: {
    todos: [
      { text: "Learn JavaScript", done: false },
      { text: "Learn Vue", done: false },
      { text: "Play around in JSFiddle", done: true },
      { text: "Build something awesome", done: true }
    ],
    count: 0,
	},
  computed: {
    computedCounter() {
    	console.log('computedCounter called!');
    	return `computedCounter: ${this.count}`;
    }
  },
  methods: {
  	methodsCounter() {
    	console.log('methodsCounter called!');
    	return `methodsCounter: ${this.count}`;
    },
  	toggle(todo) {
    	todo.done = !todo.done
    }
  }
})