Sync in Vue 2.x

by asemahle

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.1.3/vue.js"></script>

<div id="app">
  <p>
    Value in parent: {{title}}
  </p>
  <custom-component :value_sync="title" v-on:value-change="title = arguments[0]"></custom-component>
  <button v-on:click="title = 'Changed From Parent!'">CHANGE FROM PARENT</button>
</div>

<template id="custom-component">
  <div>
    <p>
      Value in child: {{value}}
    </p>
    <button v-on:click="value = 'Changed From Child!'">CHANGE FROM CHILD</button>
  </div>
</template>

JavaScript

Vue.component('custom-component', {
  template: '#custom-component',
  props: ['value_sync'],
  data: function() {
  	return {
    	value: '',
    }
  },
  watch: {
  	'value_sync': function() {
    	this.value = this.value_sync;
    },
    'value': function() {
    	this.$emit('value-change', this.value);
    }
  },
  created() {
  	this.value = this.value_sync;
  }
});

var app = new Vue({
    el: '#app',
    data: {
        title: 'Original Value',
    }
});