现有需求：小程序用户有三种身份（公众、运维人员、领导），根据不同用户身份显示不同的tabbar

众所周知微信小程序全局文件app.json里面的"tabBar"里面的list只能放置2-5个，要想实现3个tabbar,必须得复用tabbar,三种身份都需要个人中心，剩下的是长列表（两个），表单，图表 刚好是5个，废话少说，上代码

1全局.app.json

tabbar里面的sustom要设置为true

下面展示一些 内联代码片。

// A code block
{
  "pages": [
    xxxxxx:xxxxxx
   
  ],
  "window": {
   xxxxxxxxx
  },
  "tabBar": {
    **"custom": true**,
    "color": "#7A7E83",
    "selectedColor": "#d81e06",
    "borderStyle": "black",
    "backgroundColor": "#ffffff",
    "list": [
      {
        "pagePath": "pages/Users/myrepaire/myrepaire",
        "text": "我要报修",
        "iconPath": "/images/tabbar/weixiu1.png",
        "selectedIconPath": "/images/tabbar/weixiu2.png"
      },
      {
        "pagePath": "pages/Users/myMalfunction/myMalfunction",
        "text": "我的故障",
        "iconPath": "/images/tabbar/myweixiu1.png",
        "selectedIconPath": "/images/tabbar/myweixiu2.png"
      },
      {
        "pagePath": "pages/logs/logs",
        "text": "个人中心",
        "iconPath": "/images/tabbar/user1.png",
        "selectedIconPath": "/images/tabbar/user2.png"
      },
      {
        "pagePath": "pages/weixiu/myweixiu/myweixiu",
        "text": "我的维修",
        "iconPath": "/images/tabbar/myweixiu1.png",
        "selectedIconPath": "/images/tabbar/myweixiu1.png"
      },
      {
        "pagePath": "pages/charts/charts",
        "text": "故障报表",
        "iconPath": "/images/tabbar/chart1.png",
        "selectedIconPath": "/images/tabbar/chart2.png"
      }
    ]
  },
  "sitemapLocation": "sitemap.json"
}

可以看到全局app.json里面放了5个不同的tabbar路径

2.自定义custom-tab-bar(详见微信官方文档)

index.js

Component({
  data: {
    selected: 0,
    color: "#000000",
    roleId: '',
    selectedColor: "#1396DB",
    allList: [{


      list1: [{
        pagePath: "/pages/Users/myrepaire/myrepaire",
        iconPath: "/images/tabbar/weixiu1.png",
        selectedIconPath: "/images/tabbar/weixiu2.png",
        text: "我要报修"
      }, {
        pagePath: "/pages/Users/myMalfunction/myMalfunction",
        iconPath: "/images/tabbar/myweixiu1.png",
        selectedIconPath: "/images/tabbar/myweixiu2.png",
        text: "我的故障"
      }, {
        pagePath: "/pages/logs/logs",
        text: "个人中心",
        iconPath: "/images/tabbar/user1.png",
        selectedIconPath: "/images/tabbar/user2.png"
      }],



      list2: [{
        pagePath: "/pages/weixiu/myweixiu/myweixiu",
        iconPath: "/images/tabbar/weixiu1.png",
        selectedIconPath: "/images/tabbar/weixiu2.png",
        text: "我要维修"
      }, {
        pagePath: "/pages/Users/myMalfunction/myMalfunction",
        iconPath: "/images/tabbar/myweixiu1.png",
        selectedIconPath: "/images/tabbar/myweixiu2.png",
        text: "我的维修"
      }, {
        pagePath: "/pages/logs/logs",
        text: "个人中心",
        iconPath: "/images/tabbar/user1.png",
        selectedIconPath: "/images/tabbar/user2.png"
      }],


      list3: [{
        pagePath: "/pages/Users/myrepaire/myrepaire",
        iconPath: "/images/tabbar/weixiu1.png",
        selectedIconPath: "/images/tabbar/weixiu2.png",
        text: "我要报修"
      }, {
        pagePath: "/pages/charts/charts",
        iconPath: "/images/tabbar/chart1.png",
        selectedIconPath: "/images/tabbar/chart2.png",
        text: "故障报表"
      }, {
        pagePath: "/pages/logs/logs",
        text: "个人中心",
        iconPath: "/images/tabbar/user1.png",
        selectedIconPath: "/images/tabbar/user2.png"
      }]
    }],
    list: []
  },
  attached() {
    const roleId = wx.getStorageSync('statu')
    if (roleId == 20) {
      this.setData({
        list: this.data.allList[0].list1
      })
    }else if(roleId==5){
      this.setData({
        list: this.data.allList[0].list3
      })
    }else if(roleId==102){
      this.setData({
        list: this.data.allList[0].list2
      })
    }
  },
  methods: {
    switchTab(e) {
      const data = e.currentTarget.dataset
      const url = data.path
      wx.switchTab({ url })
      this.setData({
        selected: data.index
      })
    }
  },



})

说明：

首先，小程序tabbar只识别list里面的东西

先在data中定义一个list和allList数组,把三重身份用户的list分别定义为list1,list2,list3,放入allList

const roleId = wx.getStorageSync('statu') 获取用户信息存到缓存中，根据不同和的roleId来判断是什么身份，

this.setData({ list: this.data.allList[0].list2 }) 根据身份把allList里面的子数组赋值给系统默认识别的`list``

switchTab的作用根据不同的路径切换tabbar下标

index.json

{
  "usingComponents": {}
}

index.wxml

<cover-view class="tab-bar">
  <cover-view class="tab-bar-border"></cover-view>
  <cover-view wx:for="{{list}}" wx:key="index" class="tab-bar-item" data-path="{{item.pagePath}}" data-index="{{index}}" bindtap="switchTab">
    <cover-image class="cover-image" src="{{selected === index ? item.selectedIconPath : item.iconPath}}"></cover-image>
    <cover-view class="cover-view" style="color: {{selected === index ? selectedColor : color}}">{{item.text}}</cover-view>
  </cover-view>
</cover-view>

index.js

.tab-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: 48px;
  background: white;
  display: flex;
  padding-bottom: env(safe-area-inset-bottom);
}

.tab-bar-border {
  background-color: rgba(0, 0, 0, 0.33);
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 1px;
  transform: scaleY(0.5);
}

.tab-bar-item {
  flex: 1;
  text-align: center;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-direction: column;
}

.tab-bar-item .cover-image {
  width: 44rpx;
  height: 44rpx;
}

.tab-bar-item .cover-view {
  margin-top: 8rpx;
  font-size: 24rpx;
}

最后，在tabbar里面设置过 pagePath的路径文件下的 xxx.js的onshow:function(){}里面设置

或者说凡是用到tabbar组件的页面对应的xx.js里onshow:function(){}都要按照以下进行设置
不然会出现tabbar显示与点击不同步的现象

  /**
   * 生命周期函数--监听页面显示
   */
  onShow: function () {
    if (typeof this.getTabBar === 'function' &&
      this.getTabBar()) {
      this.getTabBar().setData({
        selected: 0
      })
    }

  },

//selected: 0就是选中的tabbar下标，根据不同页面显示不同tabbar下标

结果展示