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="$route.name" :open-names="openNames" :theme="menuTheme" @on-select="changeMenu"> <template v-for="item in menuList"> <MenuItem v-if="item.children.length<=1" :name="item.children[0].name" :key="'menuitem' + item.name"> <Icon :type="item.children[0].icon || item.icon" :size="iconSize" :key="'menuicon' + item.name"></Icon> <span :key="'title' + item.name">{{ itemTitle(item.children[0]) }}</span> </MenuItem> <Submenu v-if="item.children.length > 1" :name="item.name" :key="item.name"> <template slot="title"> <Icon :type="item.icon" :size="iconSize"></Icon> <span>{{ itemTitle(item) }}</span> </template> <template v-for="child in item.children"> <!-- 添加条件判断是否还有三级菜单 v-if="child.children.length<=1" --> <MenuItem v-if="isThirdLeveMenu(child)==false" :name="child.name" :key="'menuitem' + child.name"> <Icon :type="child.icon" :size="iconSize" :key="'icon' + child.name"></Icon> <span :key="'title' + child.name">{{ itemTitle(child) }}</span> </MenuItem> <!-- 以下为新增 添加条件判断如果有三级菜单 则增加三级菜单 --> <Submenu v-if="isThirdLeveMenu(child)==true" :name="child.name" :key="'menuitem' + child.name"> <template slot="title"> <Icon :type="child.icon" :size="iconSize" :key="'icon' + child.name"></Icon> <span :key="'title' + child.name">{{ itemTitle(child) }}</span> </template> <template v-for="son in child.children"> <MenuItem :name="son.name" :key="'menuitem' + son.name"> <Icon :type="son.icon" :size="iconSize" :key="'icon' + son.name"></Icon> <span :key="'title' + son.name">{{ itemTitle(son) }}</span> </MenuItem> </template> </Submenu> <!-- 以上为新增 --> </template> </Submenu> </template> </Menu> </template>
组件中methods下添加一个方法isThirdLeveMenu,判断是否含有children属性:
methods: { changeMenu(active) { this.$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 + 'https://www.jb51.net/' + 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 + 'https://www.jb51.net/' + childObj.path + 'https://www.jb51.net/' + thirdObj.path, name: thirdObj.name } ]; } } } } vm.$store.commit('setCurrentPath', currentPathArr); return currentPathArr; };