结构示意图
├── index.html├── main.js├── router│ └── index.js # 路由配置文件├── components # 组件目录│ ├── App.vue # 根组件│ ├── Home.vue # 大的框架结构组件│ ├── TreeView.vue│ ├── TreeViewItem.vue│ └── TreeDetail.vue├── store├── index.js # 我们组装模块并导出 store 的地方├── modules # 模块目录└── menusModule.js # 菜单模块
这个多级菜单实现的功能如下:
- 1、可展示多级菜单,理论上可以展无限级菜单
- 2、当前菜单高亮功能
- 3、刷新后依然会自动定位到上一次点击的菜单,即使这个是子菜单,并且父菜单会自动展开
- 4、子菜单的显示隐藏有收起、展开,同时带有淡入效果
这个例子用到的知识点:路由、状态管理、组件。
状态管理安装:
npm install --save vuex
更多关于 vuex 的介绍可以看官方文档:https://vuex.vuejs.org/zh-cn/。
我们先来看看效果演示图:

程序员是用代码来沟通的,所以费话不多说,直接上码:
index.html
<!DOCTYPE html><html><head><meta charset="utf-8"><meta name="viewport" content="width=device-width,initial-scale=1.0"><title>Vue 实现树形菜单(多级菜单)功能模块- 云库网</title></head><body><div id="app"></div></body></html>
main.js
import Vue from 'vue'import App from './components/App'import router from './router'import store from './store/index'Vue.config.productionTip = false/* eslint-disable no-new */new Vue({el: '#app',router,store,components: {App},template: '<App/>'})
在 main.js 中引入 路由和状态管理配置
App.vue
<template><div id="app"><Home></Home></div></template><script>import Home from "./Home";export default {components: {Home},name: "App"};</script><style>* {padding: 0;margin: 0;}#app {font-family: "Avenir", Helvetica, Arial, sans-serif;-webkit-font-smoothing: antialiased;-moz-osx-font-smoothing: grayscale;color: #2c3e50;}html,body,#app,.home {height: 100%;}html,body {overflow: hidden;}</style>
Home.vue
<template><div class="home"><div class="side-bar"><Tree-view></Tree-view></div><div class="continer"><router-view></router-view></div></div></template><script>import TreeView from "./TreeView";export default {components: {TreeView},name: "Home"};</script><style scoped>.side-bar {width: 300px;height: 100%;overflow-y: auto;overflow-x: hidden;font-size: 14px;position: absolute;top: 0;left: 0;}.continer {padding-left: 320px;}</style>
这个 Home.vue 主要是用来完成页面的大框架结构。
TreeView.vue
<template><div class="tree-view-menu"><Tree-view-item :menus='menus'></Tree-view-item></div></template><script>import TreeViewItem from "./TreeViewItem";const menusData = [];export default {components: {TreeViewItem},name: "TreeViewMenu",data() {return {menus: this.$store.state.menusModule.menus};}};</script><style scoped>.tree-view-menu {width: 300px;height: 100%;overflow-y: auto;overflow-x: hidden;}.tree-view-menu::-webkit-scrollbar {height: 6px;width: 6px;}.tree-view-menu::-webkit-scrollbar-trac {-webkit-box-shadow: inset 0 0 6px rgba(0, 0, 0, 0.3);box-shadow: inset 0 0 6px rgba(0, 0, 0, 0.3);}.tree-view-menu::-webkit-scrollbar-thumb {background-color: #6e6e6e;outline: 1px solid #333;}.tree-view-menu::-webkit-scrollbar {height: 4px;width: 4px;}.tree-view-menu::-webkit-scrollbar-track {-webkit-box-shadow: inset 0 0 6px rgba(0, 0, 0, 0.3);box-shadow: inset 0 0 6px rgba(0, 0, 0, 0.3);}.tree-view-menu::-webkit-scrollbar-thumb {background-color: #6e6e6e;outline: 1px solid #708090;}</style>
这个组件也非常地简单,拿到菜单数据,传给子组件,并把菜单的滚动条样式修改了下。
TreeViewItem.vue
<template><div class="tree-view-item"><div class="level" :class="'level-'+ menu.level" v-for="menu in menus" :key="menu.id"><div v-if="menu.type === 'link'"><router-link class="link" v-bind:to="menu.url" @click.native="toggle(menu)">{{menu.name}}</router-link></div><div v-if="menu.type === 'button'"><div class="button heading" :class="{selected: menu.isSelected,expand:menu.isExpanded}" @click="toggle(menu)">{{menu.name}}<div class="icon"><svg xmlns="http://www.w3.org/2000/svg" focusable="false" viewBox="0 0 24 24"><path d="M8.59 16.34l4.58-4.59-4.58-4.59L10 5.75l6 6-6 6z "></path></svg></div></div><transition name="fade"><div class="heading-children" v-show="menu.isExpanded" v-if="menu.subMenu"><Tree-view-item :menus='menu.subMenu'></Tree-view-item></div></transition></div></div></div></template><script>export default {name: "TreeViewItem",props: ["menus"],created() {this.$store.commit("firstInit", { url: this.$route.path });},methods: {toggle(menu) {this.$store.commit("findParents", { menu });}}};</script><style scoped>a {text-decoration: none;color: #333;}.link,.button {display: block;padding: 10px 15px;transition: background-color 0.2s ease-in-out 0s, color 0.3s ease-in-out 0.1s;-moz-user-select: none;-webkit-user-select: none;-ms-user-select: none;-khtml-user-select: none;user-select: none;}.button {position: relative;}.link:hover,.button:hover {color: #1976d2;background-color: #eee;cursor: pointer;}.icon {position: absolute;right: 0;display: inline-block;height: 24px;width: 24px;fill: currentColor;transition: -webkit-transform 0.15s;transition: transform 0.15s;transition: transform 0.15s, -webkit-transform 0.15s;transition-timing-function: ease-in-out;}.heading-children {padding-left: 14px;overflow: hidden;}.expand {display: block;}.collapsed {display: none;}.expand .icon {-webkit-transform: rotate(90deg);transform: rotate(90deg);}.selected {color: #1976d2;}.fade-enter-active {transition: all 0.5s ease 0s;}.fade-enter {opacity: 0;}.fade-enter-to {opacity: 1;}.fade-leave-to {height: 0;}</style>
上面的这个组件才是这个树型结构重点代码,用了递归的思想来实现这个树型菜单。
TreeViewDetail.vue
<template><h3>这里是{{currentRoute}}导航详情</h3></template><script>export default {name: "TreeViewDetail",data() {return {currentRoute: this.$route.path};},watch: {//监听路由,只要路由有变化(路径,参数等变化)都有执行下面的函数$route: {handler: function(val, oldVal) {this.currentRoute = val.name;},deep: true}}};</script><style scoped>h3 {margin-top: 10px;font-weight: normal;}</style>
router/index.js
import Vue from 'vue';import Router from 'vue-router';import App from '@/components/App';import TreeViewDetail from '@/components/TreeViewDetail';Vue.use(Router)export default new Router({linkActiveClass: 'selected',routes: [{path: '/',name: 'App',component: App},{path: '/detail/quickstart',name: 'quickstart',component: TreeViewDetail},{path: '/detail/tutorial',name: 'tutorial',component: TreeViewDetail},{path: '/detail/toh-pt1',name: 'toh-pt1',component: TreeViewDetail},{path: '/detail/toh-pt2',name: 'toh-pt2',component: TreeViewDetail},{path: '/detail/toh-pt3',name: 'toh-pt3',component: TreeViewDetail},{path: '/detail/toh-pt4',name: 'toh-pt4',component: TreeViewDetail},{path: '/detail/toh-pt5',name: 'toh-pt5',component: TreeViewDetail},{path: '/detail/toh-pt6',name: 'toh-pt6',component: TreeViewDetail},{path: '/detail/architecture',name: 'architecture',component: TreeViewDetail},{path: '/detail/displaying-data',name: 'displaying-data',component: TreeViewDetail},{path: '/detail/template-syntax',name: 'template-syntax',component: TreeViewDetail},{path: '/detail/lifecycle-hooks',name: 'lifecycle-hooks',component: TreeViewDetail},{path: '/detail/component-interaction',name: 'component-interaction',component: TreeViewDetail},{path: '/detail/component-styles',name: 'component-styles',component: TreeViewDetail},{path: '/detail/dynamic-component-loader',name: 'dynamic-component-loader',component: TreeViewDetail},{path: '/detail/attribute-directives',name: 'attribute-directives',component: TreeViewDetail},{path: '/detail/structural-directives',name: 'structural-directives',component: TreeViewDetail},{path: '/detail/pipes',name: 'pipes',component: TreeViewDetail},{path: '/detail/animations',name: 'animations',component: TreeViewDetail},{path: '/detail/user-input',name: 'user-input',component: TreeViewDetail},{path: '/detail/forms',name: 'forms',component: TreeViewDetail},{path: '/detail/form-validation',name: 'form-validation',component: TreeViewDetail},{path: '/detail/reactive-forms',name: 'reactive-forms',component: TreeViewDetail},{path: '/detail/dynamic-form',name: 'dynamic-form',component: TreeViewDetail},{path: '/detail/bootstrapping',name: 'bootstrapping',component: TreeViewDetail},{path: '/detail/ngmodule',name: 'ngmodule',component: TreeViewDetail},{path: '/detail/ngmodule-faq',name: 'ngmodule-faq',component: TreeViewDetail},{path: '/detail/dependency-injection',name: 'dependency-injection',component: TreeViewDetail},{path: '/detail/hierarchical-dependency-injection',name: 'hierarchical-dependency-injection',component: TreeViewDetail},{path: '/detail/dependency-injection-in-action',name: 'dependency-injection-in-action',component: TreeViewDetail},{path: '/detail/http',name: 'http',component: TreeViewDetail},{path: '/detail/router',name: 'router',component: TreeViewDetail},{path: '/detail/testing',name: 'testing',component: TreeViewDetail},{path: '/detail/cheatsheet',name: 'cheatsheet',component: TreeViewDetail},{path: '/detail/i18n',name: 'i18n',component: TreeViewDetail},{path: '/detail/language-service',name: 'language-service',component: TreeViewDetail},{path: '/detail/security',name: 'security',component: TreeViewDetail},{path: '/detail/setup',name: 'setup',component: TreeViewDetail},{path: '/detail/setup-systemjs-anatomy',name: 'setup-systemjs-anatomy',component: TreeViewDetail},{path: '/detail/browser-support',name: 'browser-support',component: TreeViewDetail},{path: '/detail/npm-packages',name: 'npm-packages',component: TreeViewDetail},{path: '/detail/typescript-configuration',name: 'typescript-configuration',component: TreeViewDetail},{path: '/detail/aot-compiler',name: 'aot-compiler',component: TreeViewDetail},{path: '/detail/metadata',name: 'metadata',component: TreeViewDetail},{path: '/detail/deployment',name: 'deployment',component: TreeViewDetail},{path: '/detail/upgrade',name: 'upgrade',component: TreeViewDetail},{path: '/detail/ajs-quick-reference',name: 'ajs-quick-reference',component: TreeViewDetail},{path: '/detail/visual-studio-2015',name: 'visual-studio-2015',component: TreeViewDetail},{path: '/detail/styleguide',name: 'styleguide',component: TreeViewDetail},{path: '/detail/glossary',name: 'glossary',component: TreeViewDetail},{path: '/detail/api',name: 'api',component: TreeViewDetail}]})
store/module/menusModule.js
let menus = [{ id: 1, level: 1, name: '快速上手', type: "link", url: "/detail/quickstart" },{id: 2,level: 1,name: '教程',type: "button",isExpanded: false,isSelected: false,subMenu: [{ id: 21, level: 2, name: '简介', type: "link", url: "/detail/tutorial" },{ id: 22, level: 2, name: '英雄编辑器', type: "link", url: "/detail/toh-pt1" },{ id: 23, level: 2, name: '主从结构', type: "link", url: "/detail/toh-pt2" },{ id: 24, level: 2, name: '多个组件', type: "link", url: "/detail/toh-pt3" },{ id: 25, level: 2, name: '服务', type: "link", url: "/detail/toh-pt4" },{ id: 26, level: 2, name: '路由', type: "link", url: "/detail/toh-pt5" },{ id: 27, level: 2, name: 'HTTP', type: "link", url: "/detail/toh-pt6" },]},{id: 3,level: 1,name: '核心知识',type: "button",isExpanded: false,isSelected: false,subMenu: [{ id: 31, level: 2, name: '架构', type: "link", url: "/detail/architecture" },{id: 32,level: 2,name: '模板与数据绑定',type: "button",isExpanded: false,isSelected: false,subMenu: [{ id: 321, level: 3, name: '显示数据', type: "link", url: "/detail/displaying-data" },{ id: 322, level: 3, name: '模板语法', type: "link", url: "/detail/template-syntax" },{ id: 323, level: 3, name: '生命周期钩子', type: "link", url: "/detail/lifecycle-hooks" },{ id: 324, level: 3, name: '组件交互', type: "link", url: "/detail/component-interaction" },{ id: 325, level: 3, name: '组件样式', type: "link", url: "/detail/component-styles" },{ id: 326, level: 3, name: '动态组件', type: "link", url: "/detail/dynamic-component-loader" },{ id: 327, level: 3, name: '属性型指令', type: "link", url: "/detail/attribute-directives" },{ id: 328, level: 3, name: '结构型指令', type: "link", url: "/detail/structural-directives" },{ id: 329, level: 3, name: '管道', type: "link", url: "/detail/pipes" },{ id: 3210, level: 3, name: '动画', type: "link", url: "/detail/animations" },]},{id: 33,level: 2,name: '表单',type: "button",isExpanded: false,isSelected: false,subMenu: [{ name: '用户输入', type: "link", url: "/detail/user-input" },{ name: '模板驱动表单', type: "link", url: "/detail/forms" },{ name: '表单验证', type: "link", url: "/detail/form-validation" },{ name: '响应式表单', type: "link", url: "/detail/reactive-forms" },{ name: '动态表单', type: "link", url: "/detail/dynamic-form" }]},{ id: 34, level: 2, name: '引用启动', type: "link", url: "/detail/bootstrapping" },{id: 35,level: 2,name: 'NgModules',type: "button",isExpanded: false,isSelected: false,subMenu: [{ id: 341, level: 3, name: 'NgModule', type: "link", url: "/detail/ngmodule" },{ id: 342, level: 3, name: 'NgModule 常见问题', type: "link", url: "/detail/ngmodule-faq" }]},{id: 36,level: 2,name: '依赖注入',type: "button",isExpanded: false,isSelected: false,subMenu: [{ id: 361, level: 3, name: '依赖注入', type: "link", url: "/detail/dependency-injection" },{ id: 362, level: 3, name: '多级注入器', type: "link", url: "/detail/hierarchical-dependency-injection" },{ id: 363, level: 3, name: 'DI 实例技巧', type: "link", url: "/detail/dependency-injection-in-action" }]},{ id: 37, level: 2, name: 'HttpClient', type: "link", url: "/detail/http" },{ id: 38, level: 2, name: '路由与导航', type: "link", url: "/detail/router" },{ id: 39, level: 2, name: '测试', type: "link", url: "/detail/testing" },{ id: 310, level: 2, name: '速查表', type: "link", url: "/detail/cheatsheet" },]},{id: 4,level: 1,name: '其它技术',type: "button",isExpanded: false,isSelected: false,subMenu: [{ id: 41, level: 2, name: '国际化(i18n)', type: "link", url: "/detail/i18n" },{ id: 42, level: 2, name: '语言服务', type: "link", url: "/detail/language-service" },{ id: 43, level: 2, name: '安全', type: "link", url: "/detail/security" },{id: 44,level: 2,name: '环境设置与部署',type: "button",isExpanded: false,isSelected: false,subMenu: [{ id: 441, level: 3, name: '搭建本地开发环境', type: "link", url: "/detail/setup" },{ id: 442, level: 3, name: '搭建方式剖析', type: "link", url: "/detail/setup-systemjs-anatomy" },{ id: 443, level: 3, name: '浏览器支持', type: "link", url: "/detail/browser-support" },{ id: 444, level: 3, name: 'npm 包', type: "link", url: "/detail/npm-packages" },{ id: 445, level: 3, name: 'TypeScript 配置', type: "link", url: "/detail/typescript-configuration" },{ id: 446, level: 3, name: '预 (AoT) 编译器', type: "link", url: "/detail/aot-compiler" },{ id: 447, level: 3, name: '预 (AoT) 编译器', type: "link", url: "/detail/metadata" },{ id: 448, level: 3, name: '部署', type: "link", url: "/detail/deployment" }]},{id: 45,level: 2,name: '升级',type: "button",isExpanded: false,isSelected: false,subMenu: [{ id: 451, level: 3, name: '从 AngularJS 升级', type: "link", url: "/detail/upgrade" },{ id: 452, level: 3, name: '升级速查表', type: "link", url: "/detail/ajs-quick-reference" }]},{ id: 46, level: 2, name: 'Visual Studio 2015 快速上手', type: "link", url: "/detail/visual-studio-2015" },{ id: 47, level: 2, name: '风格指南', type: "link", url: "/detail/styleguide" },{ id: 48, level: 2, name: '词汇表', type: "link", url: "/detail/glossary" }]},{ id: 5, level: 1, name: 'API 参考手册', type: "link", url: "/detail/api" }];let levelNum = 1;let startExpand = []; // 保存刷新后当前要展开的菜单项function setExpand(source, url) {let sourceItem = '';for (let i = 0; i < source.length; i++) {sourceItem = JSON.stringify(source[i]); // 把菜单项转为字符串if (sourceItem.indexOf(url) > -1) { // 查找当前 URL 所对应的子菜单属于哪一个祖先菜单if (source[i].type === 'button') { // 导航菜单为按钮source[i].isSelected = true; // 设置选中高亮source[i].isExpanded = true; // 设置为展开startExpand.push(source[i]);// 递归下一级菜单,以此类推setExpand(source[i].subMenu, url);}break;}}}const state = {menus,levelNum};const mutations = {findParents(state, payload) {if (payload.menu.type === "button") {payload.menu.isExpanded = !payload.menu.isExpanded;} else if (payload.menu.type === "link") {if (startExpand.length > 0) {for (let i = 0; i < startExpand.length; i++) {startExpand[i].isSelected = false;}}startExpand = []; // 清空展开菜单记录项setExpand(state.menus, payload.menu.url);};},firstInit(state, payload) {setExpand(state.menus, payload.url);}}export default {state,mutations};
在使用状态管理时,我们一定要记住,一旦数据写到了 state 中时,就不能再添加其它属性了,什么时间?就拿上面的 menus 数据来说,比如,本来菜单数据中没有 isExpanded 这个字段的,然后你在 mutations 的方法中给 menus 对象添加了一个 isExpanded 属性,但你会发现属性是不会被状态管理追踪到的,所以我们一开始就给这个数据添加了 isExpanded 和 isSelected 。
store/index.js
import Vue from 'vue'import Vuex from 'vuex'import menusModule from './module/menusModule'Vue.use(Vuex);const store = new Vuex.Store({modules: {menusModule}})export default store;
上面这个例子在使用状态管理时,把菜单的相关配置封装成模块,然后再引入。如果把状态管理写成模块的形式的话,在调用这个模块中的状态时就需要注意了,写法可以参数示例中的代码。
上面这个例子可以直接用到自己的项目中,只要你理解了其中的思想,其他的都不是问题。Vue 实现树形菜单功能模块之旅只能带你到这里了。
