最近在用 iview-admin的Vue后台模板，从git上下载后发现左侧导航栏最多支持到二级菜单,也发现很多童鞋在问如何实现三级菜单。在实际的应用场景中还是会出现三级菜单的需求的，木有其他好办法，只能自己手动改代码了。
1. 第一步：首先改写VUE中的模板，修改sidebarMenu.vue文件，文件具体目录建下图：
将Menu导航菜单组件的的二级嵌套结构改为三级嵌套，无非就是判断二级路由页面下是否有children属性及是否含有子元素，有的话直接v-for循环生成子元素标签，新结构如下：
<template>
<Menu ref="sideMenu" :active-name="$route.name" :open-names="openNames" :theme="menuTheme" width="auto" @on-select="changeMenu">
<template v-for="item in menuList">
<MenuItem v-if="item.children.length<=1" :name="item.children[0].name" :key="‘menuitem‘ + item.name">
<Icon :type="item.children[0].icon || item.icon" :size="iconSize" :key="‘menuicon‘ + item.name"></Icon>
<span class="layout-text" :key="‘title‘ + item.name">{{ itemTitle(item.children[0]) }}</span>
</MenuItem>
<Submenu v-if="item.children.length > 1" :name="item.name" :key="item.name">
<template slot="title">
<Icon :type="item.icon" :size="iconSize"></Icon>
<span class="layout-text">{{ itemTitle(item) }}</span>
</template>
<template v-for="child in item.children">
<!-- 添加条件判断是否还有三级菜单 v-if="child.children.length<=1" -->
<MenuItem v-if="isThirdLeveMenu(child)==false" :name="child.name" :key="‘menuitem‘ + child.name">
<Icon :type="child.icon" :size="iconSize" :key="‘icon‘ + child.name"></Icon>
<span class="layout-text" :key="‘title‘ + child.name">{{ itemTitle(child) }}</span>
</MenuItem>
<!-- 以下为新增 添加条件判断如果有三级菜单 则增加三级菜单 -->
<Submenu v-if="isThirdLeveMenu(child)==true" :name="child.name" :key="‘menuitem‘ + child.name">
<template slot="title">
<Icon :type="child.icon" :size="iconSize" :key="‘icon‘ + child.name"></Icon>
<span class="layout-text" :key="‘title‘ + child.name">{{ itemTitle(child) }}</span>
</template>
<template v-for="son in child.children">
<MenuItem :name="son.name" :key="‘menuitem‘ + son.name">
<Icon :type="son.icon" :size="iconSize" :key="‘icon‘ + son.name"></Icon>
<span class="layout-text" :key="‘title‘ + son.name">{{ itemTitle(son) }}</span>
</MenuItem>
</template>
</Submenu>
<!-- 以上为新增 -->
</template>
</Submenu>
</template>
</Menu>
</template>组件中methods下添加一个方法isThirdLeveMenu,判断是否含有children属性:
methods: {
changeMenu(active) {
this.$emit("on-change", active);
},
itemTitle(item) {
if (typeof item.title === "object") {
return this.$t(item.title.i18n);
} else {
return item.title;
}
},
isThirdLeveMenu(child){
if(child.children){
if(child.children.length>0)return true;
else return false;
}
else {
return false;
}
}
},第二步：修改创建当前path路径的逻辑方法：setCurrentPath ,在libs文件夹下util.js文件中：
util.setCurrentPath = function (vm, name) {
let title = ‘‘;
let isOtherRouter = false;
vm.$store.state.app.routers.forEach(item => {
if (item.children.length === 1) {
if (item.children[0].name === name) {
title = util.handleTitle(vm, item);
if (item.name === ‘otherRouter‘) {
isOtherRouter = true;
}
}
} else {
item.children.forEach(child => {
if (child.name === name) {
title = util.handleTitle(vm, child);
if (item.name === ‘otherRouter‘) {
isOtherRouter = true;
}
}
});
}
});
let currentPathArr = [];
//去首页
if (name === ‘home_index‘) {
currentPathArr = [
{
title: util.handleTitle(vm, util.getRouterObjByName(vm.$store.state.app.routers, ‘home_index‘)),
path: ‘‘,
name: ‘home_index‘
}
];
}
//去导航菜单一级页面或者OtherRouter路由中的页面
else if ((name.indexOf(‘_index‘) >= 0 || isOtherRouter) && name !== ‘home_index‘) {
currentPathArr = [
{
title: util.handleTitle(vm, util.getRouterObjByName(vm.$store.state.app.routers, ‘home_index‘)),
path: ‘/home‘,
name: ‘home_index‘
},
{
title: title,
path: ‘‘,
name: name
}
];
}
//去导航菜单二级页面或三级页面
else {
let currentPathObj = vm.$store.state.app.routers.filter(item => {
var hasMenu;
if (item.children.length <= 1) {
hasMenu = item.children[0].name === name;
return hasMenu;
} else {
let i = 0;
let childArr = item.children;
let len = childArr.length;
while (i < len) {
//如果是三级页面按钮，则在二级按钮数组中找不到这个按钮名称
//需要二级页面下可能出现三级子菜单的情况逻辑加入
if (childArr[i].name === name) {
hasMenu = true;
return hasMenu;
}
i++;
}
//如果一级，二级菜单下都没有此按钮名称，则遍历三级菜单
if(!hasMenu){
for(let m=0;m<childArr.length;m++){
if(!childArr[m].children) continue;
let sonArr = childArr[m].children;
for(let n=0;n<sonArr.length;n++){
if(sonArr[n].name === name){
hasMenu = true;
return hasMenu;
}
}
}
}
return false;
}
})[0];
if (currentPathObj.children.length <= 1 && currentPathObj.name === ‘home‘) {
currentPathArr = [
{
title: ‘首页‘,
path: ‘‘,
name: ‘home_index‘
}
];
} else if (currentPathObj.children.length <= 1 && currentPathObj.name !== ‘home‘) {
currentPathArr = [
{
title: ‘首页‘,
path: ‘/home‘,
name: ‘home_index‘
},
{
title: currentPathObj.title,
path: ‘‘,
name: name
}
];
} else {
//如果是三级页面按钮，则在二级按钮数组中找不到这个按钮名称
//需要二级页面下可能出现三级子菜单的情况逻辑加入
let childObj = currentPathObj.children.filter((child) => {
return child.name === name;
})[0];
// let thirdLevelObj =
console.log(childObj)
//二级页面
if (childObj) {
currentPathArr = [
{
title: ‘首页‘,
path: ‘/home‘,
name: ‘home_index‘
},
{
title: currentPathObj.title,
path: ‘‘,
name: currentPathObj.name
},
{
title: childObj.title,
path: currentPathObj.path + ‘/‘ + childObj.path,
name: name
}
];
}
//childobj为undefined，再从三级页面中遍历
else {
let thirdObj;
let childObj = currentPathObj.children.filter((child) => {
let hasChildren;
hasChildren = child.name === name;
if (hasChildren) return hasChildren
if (child.children) {
let sonArr = child.children;
for (let n = 0; n < sonArr.length; n++) {
if (sonArr[n].name === name) {
thirdObj = sonArr[n];
hasChildren = true;
return hasChildren;
}
}
}
return hasChildren
})[0];
if(thirdObj && childObj){
currentPathArr = [
{
title: ‘首页‘,
path: ‘/home‘,
name: ‘home_index‘
},
{
title: currentPathObj.title,
path: ‘‘,
name: currentPathObj.name
},
{
title: childObj.title,
path: ‘‘, //设为空是因为此二级菜单没有实际页面且用于面包屑组件显示，path为空的将不可单击
name: childObj.name
},
{
title: thirdObj.title,
path: currentPathObj.path + ‘/‘ + childObj.path + ‘/‘ + thirdObj.path,
name: thirdObj.name
}
];
}
}
}
}
vm.$store.commit(‘setCurrentPath‘, currentPathArr);
return currentPathArr;
};第三步：建立三级页面test-child.vue,testcaca.vue和三级路由的容器组件artical-publish-center.vue
artical-publish-center.vue结构如下图： 要有<rout-view>标签
其他两个三级页面vue随便写了：
第四步：到这里，容器可以实现期待已久三级菜单了，^_^. 在router里添加三级页面路由，router文件夹下router.js中：
加到appRouter中吧,可以放到title: ‘组件‘的children数组中：
{
path: ‘artical-publish‘,
title: ‘用户配置‘,
name: ‘artical-publish‘,
icon: ‘compose‘,
component: () => import(‘@/views/test/artical-publish-center.vue‘), //引用三级页面的中间容器层
children:[
{
path: ‘testcaca‘,
icon: ‘ios-pause‘,
name: ‘testcaca‘,
title: ‘test4‘,
component: () => import(‘@/views/test/testcaca.vue‘)
},
{
path: ‘test-child‘,
icon: ‘ios-pause‘,
name: ‘test-child‘,
title: ‘test-child‘,
component: () => import(‘@/views/test/test-child.vue‘)
}
]
} 最后保存，运行你的项目，看下三级菜单出来了吧：
