Vue 2.0 Hello World

HTML

<script src="https://unpkg.com/vue"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
<div id="app">
<form @keydown="hasChanged=true">
<input type="text"/>
<input type="text"/>
<input type="text"/>


</form>
<button class="btn btn-primary" :class="{disabled: !hasChanged}" @click="hasChanged=false">
Click
</button>
  <p>{{ message }}</p>
</div>

JavaScript

new Vue({
  el: '#app',
  data: {
    message: 'Hello Vue.js!',
    hasChanged: false
  },
  methods: {
  	formChange () {
    	this.message = 'formChange'
    }
  }
})