看，田野里的玉米露出了笑脸，秋风吹过，闪烁着太阳的光芒，秋天是金色的。看满山的枫叶，红得就像一团火焰在熊熊燃烧，散发着生机，秋天是红色的。呵呵，我们都错了，秋天不是金黄的，也不是红色的，秋天是五颜六色的。
早就实现了功能，但是发现点击的时候，选中的菜单项背景色会变白，周五时候仔细观察了一下，发现并不是调整样式的问题，而是选项没有被选中，于是好好研究了一下组件递归这块，总结记录一下心路历程
一、概念
递归：递归其实说白了，就是自己调用自己，样子就像是套娃一个套一个的，小时候玩过一个游戏汉诺塔就是利用的递归原理：
函数递归：函数利用函数名还调用自己 组件递归：所以组件递归利用的是vue组件中的name属性来实现的
二、需求
实现可折叠动态渲染多级侧边栏导航
三、分析
1、观察到侧边栏导航是一级一级的，第二级就相当于再重复一遍第一级 2、有一个特点，有的菜单有下级，有的没有下一级 3、动态渲染，说明是从后台接口获取的树类型数据，动态的渲染上去 四、代码实现 1、首先先执行一下文档里的demo试一下：
文档：element文档
2、改成自己需要的样式，第一次是这么写的
父组件SideBar
<template>
<el-menu class="menu-wrap" :default-active="menuActiveName || 'home'" :active="menuActiveName || 'home'"
:collapse="sidebarFold" :collapseTransition="false" :unique-opened="true" @select="selectItem">
<template>
<el-menu-item @click="sidebarFold = !sidebarFold">
<i v-show="!sidebarFold" class="el-icon-s-fold"></i>
<i v-show="sidebarFold" class="el-icon-s-unfold"></i>
<span slot="title" class="sidebar-one">导航列表</span>
</el-menu-item>
</template>
<!-- <side-bar-item :list="menuList"></side-bar-item>-->
<template v-for="(item,index) in menuList" class="menu">
<!-- 标题 -->
<template v-if="item.children.length" >
<el-submenu :key="index" :index="item.id" class="sub-menu-item">
<template :index="item.index" slot="title">
<!-- <i :class="item.icon"></i>-->
<i class="iconfont icon-danganjianying"></i>
<span>{{item.name}}</span>
</template>
<el-menu-item-group class="menu-item-group">
<side-bar-item :list="item.children"></side-bar-item>
</el-menu-item-group>
</el-submenu>
</template>
<!-- 选项 -->
<template v-else>
<el-menu-item :key="index" :index="item.id" class="menu-item">
<!-- <i :class="item.icon"></i>-->
<i class="iconfont icon-danganjianying"></i>
<span>{{item.name}}</span>
</el-menu-item>
</template>
</template>
</el-menu>
</template>
<script>
export default {
name: 'SideBar',
components: {
SideBarItem: () => import('@/components/common/SideBarItem')
},
data () {
return {
}
},
mounted () {
},
methods: {
selectItem(name, path){
// alert(name)
this.$router.push(path)
this.$store.commit('common/updateMenuActiveName', name)
}
},
computed: {
menuList: {
get () {
return this.$store.state.common.menuList
},
set (val) {
this.$store.commit('common/updateMenuList', val)
}
},
menuActiveName: {
get () { return this.$store.state.common.menuActiveName },
set (val) { this.$store.commit('common/updateMenuActiveName', val) }
},
sidebarFold: {
get() {return this.$store.state.common.sidebarFold;},
set(val) {this.$store.commit("common/updateSidebarFold", val);}
},
},
}
</script>
<style lang="less" scoped>
.menu-wrap{
width: 200px;
min-height: 1020px;
background: url('../../assets/img/sidebar_bg.png') no-repeat;
background-size: 100% 100%;
}
/deep/ .el-menu{
background-color: transparent !important;
.iconfont {
font-size: 18px;
vertical-align: sub;
margin-right: 5px;
display: inline-block;
width: 20px;
text-align: center;
}
}
/deep/ .el-menu-item,
/deep/ .el-submenu__title{
color: #fff;
.iconfont{
color: #fff;
}
}
/deep/ .el-menu-item span,
/deep/ .el-submenu__title span{
padding-left: 10px;
}
/deep/ .el-menu-item.is-active {
-webkit-box-shadow: inset 5px 100px 0px -2px #0064B6;
box-shadow: inset 5px 100px 0px -2px #0064B6;
}
/deep/ .el-submenu__title:hover,
/deep/ .el-menu-item:hover{
background: #0064B6;
}
/deep/ .el-menu-item-group__title{
padding: 0;
}
</style>
子组件SideBarItem
<template>
<div class="menu">
<template v-for="(item,index) in list">
<!-- 标题 -->
<template v-if="item.children.length" >
<el-submenu :key="index" :index="item.id" class="sub-menu-item">
<template :index="item.index" slot="title">
<!-- <i :class="item.icon"></i>-->
<i class="iconfont icon-danganjianying"></i>
<span>{{item.name}}</span>
</template>
<el-menu-item-group class="menu-item-group">
<side-bar-item :list="item.children"></side-bar-item>
</el-menu-item-group>
</el-submenu>
</template>
<!-- 选项 -->
<template v-else>
<el-menu-item :key="index" :index="item.id" class="menu-item" @click="selectItem(item.name, item.path)">
<!-- <i :class="item.icon"></i>-->
<i class="iconfont icon-danganjianying"></i>
<span>{{item.name}}</span>
</el-menu-item>
</template>
</template>
</div>
</template>
<script>
export default {
name: 'SideBarItem',
// props: ['list'],
props: {
list: {
type: Array || ''
}
},
data () {
return {
treeData: [{
label: '某某省',
children: [{
label: '中共某某省委员会'
// children: [{
// label: '三级 1-1-1'
// }]
}, {
label: '中共某某省办公室'
}, {
label: '中共某某省组织部'
}
]
}
],
isShow: false
// menuList: []
}
},
mounted () {
this.loadSysMenu()
},
methods: {
loadSysMenu () {
// console.log('menu', this.menuList)
},
// personManage (name) {
// if (name === '人员管理') {
// this.isShow = !this.$store.state.common.rbflag
// // alert('111' + this.isShow)
// this.$store.commit('common/updateShowRbox', this.isShow)
// }
// },
selectItem(name, path){
// alert(name)
this.$router.push(path)
this.$store.commit('common/updateMenuActiveName', name)
}
},
}
</script>
<style lang="less" scoped>
.menu{
width: 100%;
.sub-menu-item /deep/ .el-submenu__title,
.menu-item{
height: 60px;
line-height: 60px;
text-align: left;
//padding-left: 30px !important;
//border-bottom: 1px solid #000;
//border-right: 1px solid #000;
color: #fff;
}
.sub-menu-item .el-menu-item{
padding-right: 0;
}
/deep/ .el-menu-item .is-active{
background-color: #0087df;
}
.menu-item:hover,
/deep/ .el-submenu__title:hover{
background-color: #0087df;
}
.menu-item span,
.sub-menu-item /deep/ .el-submenu__title>span{
font-weight: 700;
}
.menu-item-group /deep/ .el-menu-item-group__title{
padding: 0 !important;
}
.menu-item-group .menu-item{
background: url('../../assets/img/sidebar_bg.png') no-repeat;
}
.el-menu-item-group span{
font-weight: normal;
}
}
</style>
后来发现折叠不成功，而且选中之后选中项样式没变，后来发现是没选中，研究发现是因为多嵌套了一层div，而且用了el-menu-item-group项目中并不需要这个，于是改进如下：
父组件SideBar
<template>
<el-menu class="menu-wrap" :default-active="menuActiveName" :collapse="sidebarFold" :collapseTransition="false" :unique-opened="true">
<template>
<el-menu-item @click="foldSideBar">
<i v-show="!sidebarFold" class="el-icon-s-fold"></i>
<i v-show="sidebarFold" class="el-icon-s-unfold"></i>
<span slot="title" class="sidebar-one">导航列表</span>
</el-menu-item>
</template>
<side-bar-item v-for="menu in menuList" :key="menu.id" :menu="menu"></side-bar-item>
</el-menu>
</template>
<script>
export default {
name: 'SideBar',
components: {
SideBarItem: () => import('@/components/common/SideBarItem')
},
data () {
return {
}
},
mounted () {
},
methods: {
foldSideBar(){
this.sidebarFold = !this.sidebarFold
this.menuActiveName = 'NAV'
}
},
computed: {
menuList: {
get () {
return this.$store.state.common.menuList
},
set (val) {
this.$store.commit('common/updateMenuList', val)
}
},
menuActiveName: {
get () {
console.log(this.$store.state.common.menuActiveName)
return this.$store.state.common.menuActiveName
},
set (val) {
this.$store.commit('common/updateMenuActiveName', val)
}
},
sidebarFold: {
get() {return this.$store.state.common.sidebarFold;},
set(val) {this.$store.commit("common/updateSidebarFold", val);}
},
},
}
</script>
<style lang="less" scoped>
.menu-wrap{
width: 200px;
min-height: 1020px;
background: url('../../assets/img/sidebar_bg.png') no-repeat;
background-size: 100% 100%;
}
/deep/ .el-menu{
background-color: transparent !important;
.iconfont {
font-size: 18px;
vertical-align: sub;
margin-right: 5px;
display: inline-block;
width: 20px;
text-align: center;
}
}
/deep/ .el-menu-item,
/deep/ .el-submenu__title{
color: #fff;
.iconfont{
color: #fff;
}
}
/deep/ .el-menu-item span,
/deep/ .el-submenu__title span{
padding-left: 10px;
}
/deep/ .el-menu-item.is-active {
-webkit-box-shadow: inset 5px 100px 0px -2px #0064B6;
box-shadow: inset 5px 100px 0px -2px #0064B6;
}
/deep/ .el-submenu__title:hover,
/deep/ .el-menu-item:hover{
background: #0064B6;
}
</style>
子组件SideBarItem
<template>
<!-- 该菜单下还有子菜单-->
<el-submenu v-if="menu.children.length" :index="menu.code" :popper-append-to-body=false>
<template slot="title">
<i class="iconfont icon-danganjianying"></i>
<span>{{ menu.name }}</span>
</template>
<side-bar-item v-for="item in menu.children" :key="item.id" :menu="item"></side-bar-item>
</el-submenu>
<!-- 该菜单下无子菜单-->
<el-menu-item v-else :index="menu.code" @click="selectItem(menu.code, menu.path)">
<i class="iconfont icon-danganjianying"></i>
<span>{{ menu.name }}</span>
</el-menu-item>
</template>
<script>
export default {
name: 'SideBarItem',
// props: ['menu'],
props: {
menu: {
type: Object || {}
}
},
data () {
return {
}
},
mounted () {
},
methods: {
selectItem(code, path){
// alert(name)
console.log(code, path)
this.$router.push(path)
this.$store.commit('common/updateMenuActiveName', code)
}
},
}
</script>
<style lang="less" scoped>
.menu{
width: 100%;
.menu-item{
height: 60px;
line-height: 60px;
text-align: left;
color: #fff;
}
.sub-menu-item .el-menu-item{
padding-right: 0;
}
/deep/ .el-menu-item .is-active{
background-color: #0087df;
}
.menu-item:hover{
background-color: #0087df;
}
.menu-item span{
font-weight: 700;
}
}
</style>
功能基本实现，但是出现一个bug，当鼠标点折叠时，会出现循环调用某个事件，导致栈溢出报错，查看文章只需对子菜单设置属性 :popper-append-to-body=“false” 即可 参考文章：Element-ui NavMenu子菜单使用递归生成时使用报错
最后附上简单的测试数据：
testData: [
{"id":"34161C2E8-7348-4439-8899-9A8039AE6AE4","pid":"0","code":"HOME","name":"首页","path":"/home","type":null,"icon":null,"sysId":"2761C2E8-7348-4439-8899-9A8039AE6AE3","orderNo":0,"isCheck":null,"children":[]},
{"id":"703DBEBD-F92C-4347-9203-F60A73153C3F","pid":"0","code":"WD","name":"温度","path":"/temperature","type":null,"icon":null,"sysId":"2AB00274-73DF-459A-A02E-C79A4D8A8929","orderNo":0,"isCheck":null,"children":[]},
{"id":"73660AB4-48D3-4BDB-86FD-C8397D4D54EC","pid":"0","code":"BJ","name":"报警","path":"/alarm","type":null,"icon":null,"sysId":"2AB00274-73DF-459A-A02E-C79A4D8A8929","orderNo":0,"isCheck":null,
"children":[
{"id":"1C99333D-886F-4AD6-93C4-7C5244E48247","pid":"73660AB4-48D3-4BDB-86FD-C8397D4D54EC","code":"FD","name":"防盗","path":"/burg","type":null,"icon":null,"sysId":"3691C2E8-8848-4439-8899-9A8039AE6AB5","orderNo":0,"isCheck":null,"children":[]},
{"id":"1DBDF678-F51F-444A-B995-61E5D9CCA5AF","pid":"73660AB4-48D3-4BDB-86FD-C8397D4D54EC","code":"JL","name":"警铃","path":"/bell","type":null,"icon":null,"sysId":"3691C2E8-8848-4439-8899-9A8039AE6AB5","orderNo":0,"isCheck":null,"children":[]},
{"id":"BFC8C2E1-0E5B-4EEE-B91D-3DABC63FF481","pid":"73660AB4-48D3-4BDB-86FD-C8397D4D54EC","code":"JS","name":"浸水","path":"/immersion","type":null,"icon":null,"sysId":"3691C2E8-8848-4439-8899-9A8039AE6AB5","orderNo":0,"isCheck":null,"children":[]},
{"id":"BFC8C2E1-0E5B-4EEE-B91D-3DABC63FF482","pid":"73660AB4-48D3-4BDB-86FD-C8397D4D54EC","code":"MJ","name":"门禁","path":"/punch","type":null,"icon":null,"sysId":"3691C2E8-8848-4439-8899-9A8039AE6AB5","orderNo":0,"isCheck":null,"children":[]},
{"id":"BFC8C2E1-0E5B-4EEE-B91D-3DABC63FF483","pid":"73660AB4-48D3-4BDB-86FD-C8397D4D54EC","code":"ZT","name":"状态","path":"/state","type":null,"icon":null,"sysId":"3691C2E8-8848-4439-8899-9A8039AE6AB5","orderNo":0,"isCheck":null,"children":[]}
]
},
{"id":"34161C2E8-7348-4439-8899-9A8039AE6AE5","pid":"0","code":"GZ","name":"工作","path":"/work","type":null,"icon":null,"sysId":"3691C2E8-8848-4439-8899-9A8039AE6AB5","orderNo":0,"isCheck":null,
"children":[]
},
{"id":"0CD6B09A-AA43-4AE9-9AC7-29BC5AC83495","pid":"0","code":"SJ","name":"数据","path":"/data","type":null,"icon":null,"sysId":"2AB00274-73DF-459A-A02E-C79A4D8A8929","orderNo":0,"isCheck":null,
"children":[]
},
{"id":"049C670D-A33E-4188-9206-B3F3B5DDE77B","pid":"0","code":"SP","name":"视频","path":"/video","type":null,"icon":null,"sysId":"3691C2E8-8848-4439-8899-9A8039AE6AB5","orderNo":0,"isCheck":null,"children":[]},
{"id":"0A15DBB6-3241-4C7F-AAD4-5417E7BBECAA","pid":"0","code":"RZ","name":"日志","path":"/log","type":null,"icon":null,"sysId":"2AB00274-73DF-459A-A02E-C79A4D8A8929","orderNo":0,"isCheck":null,
"children":[]
}
]
效果如图：
折叠后如图：
到此这篇关于vue+elementUI组件递归实现可折叠动态渲染多级侧边栏导航的文章就介绍到这了,更多相关elementUI可折叠动态侧边栏导航内容请搜索以前的文章或继续浏览下面的相关文章希望大家以后多多支持！
