elementui实现NavMenu 导航菜单与Tabs 标签页联动

技术：vue2+vuex+elementui组件库

 store/index.js文件里

import Vue from 'vue'
import Vuex from 'vuex'

Vue.use(Vuex)

export default new Vuex.Store({
  state: {
    tabList:[]
  },
  mutations: {
    addTab: (state, tab) => {
      // 如果tab已经存在，不添加新的tabs
      if (state.tabList.some(item => item.path === tab.path)) return
      state.tabList.push(tab)
    }
  },
  getters: {
    // 获取tbsList
    getTabs: (state) => {
      return state.tabList
    }
  },
  actions: {
  },
  modules: {
  }
})

功能点：
1：当前活跃的tab就是当前路由的path
2: 页面刷新，tabList数据丢失，则在刷新之前使用sessionStorage进行存储
3：删除tab的时候，活跃的tab变为被删除的前一个或者下一个，删除后重新设置活跃的tab 和tabList
4：监控路由变化，路由变化了，活跃的tab 和tabList 也要随之变化
 

<template>
  <el-tabs
    v-model="activeTab"
    closable
    @tab-remove="removeTab"
    @tab-click="clickBtn"
  >
    <el-tab-pane
      :key="index"
      v-for="(item, index) in tabList"
      :label="item.title"
      :name="item.path"
    >
      {
   
   { item.content }}
    </el-tab-pane>
  </el-tabs>
</template>

<script>
import store from '../../store'
export default {
  name: '',
  data() {
    return {
      // 当前活跃的tabs
      activeTab: '',
    }
  },
  components: {},
  computed: {
    tabList() {
      return store.getters['getTabs']
    },
  },
  watch: {
    $route: function () {
      this.setActiveTab()
      this.addTab()
    },
  },
  created() {},
  mounted() {
    this.beforeRefresh()
    this.setActiveTab()
    this.addTab()
  },
  methods: {
    // 设置活跃的tab
    setActiveTab() {
      this.activeTab = this.$route.path
    },
    // 添加tab
    addTab() {
      const { path, meta } = this.$route
      const tab = {
        path,
        title: meta.title,
      }
      store.commit('addTab', tab)
    },
    // 点击tab
    clickBtn(tab) {
      const { name } = tab
      this.$router.push({ path: name })
    },
    // 删除tab
    removeTab(target) {
      // 当前激活的tab
      let active = this.activeTab
      const tabs = this.tabList
      // 只有一个标签页的时候不允许删除
      if (tabs.length === 1) return
      if (active === target) {
        tabs.forEach((tab, index) => {
          // 如果删除的就是当前活跃的tab,就把活跃的tab变成上一个或下一个
          const nextTab = tab[index + 1] || tab[index - 1]
          if (nextTab) {
            active = nextTab.path
          }
        })
      }
      // 重新设置当前激活的选项卡和 选项卡列表
      this.activeTab = active
      store.state.tabList = tabs.filter((tab) => tab.path !== target)
    },
    // 解决刷新数据丢失问题
    beforeRefresh() {
      window.addEventListener('beforeunload', () => {
        sessionStorage.setItem('tabsView', JSON.stringify(this.tabList))
      })
      let tabSession = sessionStorage.getItem('tabsView')
      if (tabSession) {
        let oldTabs = JSON.parse(tabSession)
        if (oldTabs.length > 0) {
          store.state.tabList = oldTabs
        }
      }
    },
  },
}
</script>

补充：路由（router/index.js)

{
    path: '/layout',
    component: () => import('../layout/index.vue'),
    children: [
      {
        path: 'lay1',
        component: () => import('../views/lay/Lay1.vue'),
        meta: {
          title:'选项1'
        }
      },
      {
        path: 'lay2',
        component: () => import('../views/lay/Lay2.vue'),
        meta: {
          title:'选项2'
        }
        
      },
      {
        path: 'lay3',
        component: () => import('../views/lay/Lay3.vue'),
        meta: {
          title:'选项3'
        }
      },
      {
        path: 'lay4',
        component: () => import('../views/lay/Lay4.vue'),
        meta: {
          title:'选项4'
        }
      },
    }