1.vm.$set
问题描述:
如何在不通过循环数据给list数据添加一个showMore属性，并且在moreFun中改变这个新增属性的值，并实现双向绑定？
<template>
<div id="app">
<div class="demo">
<ul>
<template v-for="(v,index) in list">
<li>{{v.name}}</li>
<div v-show="!v.showMore">
<button @click="moreFun(index)">展示更多</button>
</div>
</template>
</ul>
</div>
</div>
</template>
<script>
export default {
name: 'app',
data() {
return {
list: [{
name: '小颖'
}, {
name: '仔仔'
}, {
name: '黑妞'
}, {
name: '土豆'
}]
}
},
methods: {
moreFun(index) {
console.log(this.list);
}
}
}
</script>
<style>
#app {
font-family: 'Avenir', Helvetica, Arial, sans-serif;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
text-align: center;
color: #2c3e50;
margin-top: 60px;
}
</style>
一开始小颖并不知道怎么做，而且小颖觉得
<div v-show="!v.showMore">
<button @click="moreFun(index)">展示更多</button>
</div>
这段代码肯定会报错，然而当小颖写上后发现，并没有，后来那位帅锅告诉我，看看vue的 vm.$set 小颖看后将moreFun方法写为:
moreFun(index) {
this.$set(this.list[index], 'showMore', true);
console.log(this.list);
}
然后就达到小颖想要的结果啦。小颖当时遇到的问题类似于这样的：
<template>
<div id="app">
<div class="demo">
<ul>
<template v-for="(v,index) in list">
<li>{{v.name}}</li>
<div v-show="!v.showMore">
<button @click="moreFun(index)">展示更多</button>
</div>
</template>
</ul>
</div>
</div>
</template>
<script>
export default {
name: 'app',
data() {
return {
list: [{
name: '小颖'
}, {
name: '仔仔'
}, {
name: '黑妞'
}, {
name: '土豆'
}]
}
},
mounted: function() {
this.list.forEach(function(element, index) {
element.showMore = false;
});
},
methods: {
moreFun(index) {
this.list[index].showMore = true;
console.log(this.list);
}
}
}
</script>
<style>
#app {
font-family: 'Avenir', Helvetica, Arial, sans-serif;
-webkit-font-smoothing: antialiased;
-moz-osx-font-smoothing: grayscale;
text-align: center;
color: #2c3e50;
margin-top: 60px;
}
</style>