<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>watch</title>
</head>
<body>
<div id="app">
<input type="checkbox" v-model=‘selected‘ @change="handle">全选/全不选
<br>
<span>
<span v-for="(item,index) in hobbyList">
<input type="checkbox" :id="item.id|handleId" :value="item.value" v-model=‘checkList‘>
<label :for="item.id|handleId" v-text="item.name">
</label>
</span>
</span>
</div>
<script src="../node_modules/vue/dist/vue.js"></script>
<script>
let vm = new Vue({
el: "#app",
data: {
hobbyList:[
{
id:1,
name:‘唱歌‘,
value:‘song‘
},
{
id:2,
name:‘跳舞‘,
value:‘dance‘
},
{
id:3,
name:‘阅读‘,
value:‘read‘
},
{
id:4,
name:‘睡觉‘,
value:‘sleep‘
}
],
// 存储选中的兴趣爱好
checkList:[],
// 存储全选按钮的选中状态
selected: false
},
// watch => 监听响应式数据的改变 (watch 监听的响应式数据必须在data中初始化) 和
// computed中的setter 类似 只不过computed 是自己单独设置的计算属性(不能和data中的冲突)
// 而 watch 只能监听 DATA 中有的属性
// => 监听器支持异步操作 computed 的getter 不支持异步获取数据
watch:{
checkList(){
this.selected = this.checkList.length === this.hobbyList.length ? true : false;
}
},
methods:{
handle(){
if(this.selected){
this.hobbyList.forEach(item => {
this.checkList.push(item.value);
});
return;
}
this.checkList = [];
}
},
filters:{
handleId(value){
return ‘hobby‘ + value;
}
},
});
</script>
</body>
</html>
