需求分析：
如图，有很多高度不固定的模块（图中只显示两个，本人项目有十三个），点击模块标题展开相应的模块，再次点击此模块匿藏，如何实现此需求并实现复用？
点击红框前：
点击后：
难点分析:
模块高度不固定。比如，本人一开始想到的方法如下：
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
<style>
.box{
height:500px;
background-color:black;
overflow: hidden;
}
.mybox-leave-active,.mybox-enter-active{
transition: all 1s ease;
}
.mybox-leave-active,.mybox-enter{
height:0px !important;
}
.mybox-leave,.mybox-enter-active{
height: 500px;
}
</style>
</head>
<body>
<p id="box">
<transition name="mybox">
<p class="box" v-show="boxshow"></p>
</transition>
<button @click="togglebox">按钮</button>
</p>
</body>
<script src="../bower_components/vue/dist/vue.js"></script>
<script>
new Vue({
el:'#box',
data:{
boxshow:false
},
methods:{
togglebox:function(){
this.boxshow = !this.boxshow;
}
}
});
</script>
</html>这种方法确实可以实现点击展开，再次点击收缩的需求，但是有一个明显的缺点：限定了容器的高度，也就是每个模块都需要固定高度，并不适用于需求场景。
解决方案：
1、实现一个函数式组件
本人命名为vertical-toggle.js
// Created by xiaoqiang on 17/04/2018.
const elTransition = '0.3s height ease-in-out, 0.3s padding-top ease-in-out, 0.3s padding-bottom ease-in-out'
const Transition = {
'before-enter' (el) {
el.style.transition = elTransition
if (!el.dataset) el.dataset = {}
el.dataset.oldPaddingTop = el.style.paddingTop
el.dataset.oldPaddingBottom = el.style.paddingBottom
el.style.height = 0
el.style.paddingTop = 0
el.style.paddingBottom = 0
},
'enter' (el) {
el.dataset.oldOverflow = el.style.overflow
if (el.scrollHeight !== 0) {
el.style.height = el.scrollHeight + 'px'
el.style.paddingTop = el.dataset.oldPaddingTop
el.style.paddingBottom = el.dataset.oldPaddingBottom
} else {
el.style.height = ''
el.style.paddingTop = el.dataset.oldPaddingTop
el.style.paddingBottom = el.dataset.oldPaddingBottom
}
el.style.overflow = 'hidden'
},
'after-enter' (el) {
el.style.transition = ''
el.style.height = ''
el.style.overflow = el.dataset.oldOverflow
},
'before-leave' (el) {
if (!el.dataset) el.dataset = {}
el.dataset.oldPaddingTop = el.style.paddingTop
el.dataset.oldPaddingBottom = el.style.paddingBottom
el.dataset.oldOverflow = el.style.overflow
el.style.height = el.scrollHeight + 'px'
el.style.overflow = 'hidden'
},
'leave' (el) {
if (el.scrollHeight !== 0) {
el.style.transition = elTransition
el.style.height = 0
el.style.paddingTop = 0
el.style.paddingBottom = 0
}
},
'after-leave' (el) {
el.style.transition = ''
el.style.height = ''
el.style.overflow = el.dataset.oldOverflow
el.style.paddingTop = el.dataset.oldPaddingTop
el.style.paddingBottom = el.dataset.oldPaddingBottom
}
}
export default {
name: 'VerticalToggle',
functional: true,
render (h, { children }) {
const data = {
on: Transition
}
return h('transition', data, children)
}
}2、引用此组件
在components中注册了此组件：
即可在teamplate中引用，请留意红框文字说明部分。
至此，Vue.js实现垂直展开、收缩不定高度模块组件实现完成及应用均已完成。
实现效果：