<template>
 <div>
 <input type='checkbox' class='input-checkbox' v-model='checked' v-on:click='checkedAll'>全选
 <template v-for='checkb in checkboxData'>
 <input type='checkbox' name='checkboxinput' class='input-checkbox' v-model='checkboxModel' value='{{checkb.id}}'>{{checkb.value}}
 </template>
 </div>
</template>

<script>
export default {
methods:{
 checkedAll: function() {
 var _this = this;
 console.log(_this.checkboxModel);
 if (this.checked) {//实现反选
 _this.checkboxModel = [];
 }else{//实现全选
 _this.checkboxModel = [];
 _this.checkboxData.forEach(function(item) {
 _this.checkboxModel.push(item.id);
 });
 }
 }
},
watch: {//深度 watcher
 'checkboxModel': {
 handler: function (val, oldVal) { 
 if (this.checkboxModel.length === this.checkboxData.length) {
 this.checked=true;
 }else{
 this.checked=false;
 }
 },
 deep: true
 }
},
data () {
 return {
 checkboxData:[{
 id:'1',
 value:'苹果'
 },{
 id:'2',
 value:'荔枝'
 },{
 id:'3',
 value:'香蕉'
 },{
 id:'4',
 value:'火龙果'
 }],
 checkboxModel:['1','3','4'],
 checked:""
 }
}
}
</script>

var vm = new Vue({
 data: {
 a: 1
 },
 watch: {
 'a': function (val, oldVal) {
 console.log('new: %s, old: %s', val, oldVal)
 },
 // 方法名
 'b': 'someMethod',
 // 深度 watcher
 'c': {
 handler: function (val, oldVal) { /* ... */ },
 deep: true
 }
 }
})
vm.a = 2 // -> new: 2, old: 1