uniapp 自定义微信小程序 tabBar 导航栏

背景

做了一个校园招聘类小程序，使用 uniapp + vue3 + uview-plus + pinia 构建，这个小程序要实现多角色登录，根据权限动态切换 tab 栏文字、图标。

使用pages.json中配置tabBar无法根据角色动态配置 tabBar，因此自定义tabBar，根据下面的截图说明的几种自定义方案，第一种使用custom-tab-bar组件，这个只有 H5 支持，使用 view 自己绘制 tabBar 也可以，我采用微信小程序自定义tabBar 这个方式。

目标

实现一个自定义 tabBar，能够根据登录角色显示不同的导航栏

参考文档

参考 uniapp 关于自定义 tabBar 的说明，
uniapp 自定义tabbar
以及微信小程序自定义tabbar的文档

项目结构

效果图

效果图2 效果图1

实现过程

添加微信小程序custom-tab-bar组件
配置pages.json
引入pinia，创建store目录
创建tabData.ts文件，放置 tabBar 数据
创建tabs目录，标签栏对应的页面
创建标签页对应的组件
在App.vue中初始化

添加微信小程序`custom-tab-bar`组件

根据文档描述需要在根目录（cli 项目在 src 目录）下创建custom-tab-bar目录，里面是小程序wxml,wxss文件，不是vue文件。

我将custom-tab-bar组件的代码放在下面了，或者可以去微信小程序文档中下载示例代码

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

/* src/custom-tab-bar/index.js */
Component({
  data: {
    selected: 0,
    color: '#333333',
    selectedColor: '#1874F5',
  },
  methods: {
    switchTab(e) {
      const data = e.currentTarget.dataset
      const url = '/' + data.path
      wx.switchTab({url})
      this.setData({
        selected: data.index
      })
    }
  }
})

/* src/custom-tab-bar/index.wxss */
.tab-bar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  padding-bottom: env(safe-area-inset-bottom);
  height: 96rpx;
  background: white;
  box-shadow: 0 -4px 16px 0 #00000014;
  z-index: 10000;
}

.tab-bar-border {
  background-color: rgba(0, 0, 0, 0.33);
  position: absolute;
  left: 0;
  top: 0;
  width: 100%;
  height: 2rpx;
  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: 48rpx;
  height: 48rpx;
}

.tab-bar-item cover-view {
  font-size: 20rpx;
}

// src/custom-tab-bar/index.json
{
  "component": true,
  "usingComponents": {}
}

配置`pages.json`

pages设置中需要引入tab对应的页面，否则在小程序中会报错

tabbar设置中添加 custom: true，list列表中的配置保留，后面在页面初始化时会被自定义 tabBar 数据覆盖

{
  "pages": [ //pages数组中第一项表示应用启动页，参考：https://uniapp.dcloud.io/collocation/pages
    {
      "path": "pages/tabs/tab1",
      "style": {
        "navigationStyle": "custom"
      }
    },
    {
      "path": "pages/tabs/tab2",
      "style": {
        "navigationStyle": "custom"
      }
    },
    {
      "path": "pages/tabs/tab3",
      "style": {
        "navigationStyle": "custom"
      }
    },
    {
      "path": "pages/tabs/tab4",
      "style": {
        "navigationStyle": "custom"
      }
    },
    {
      "path": "pages/index/index",
      "style": {
        "navigationBarTitleText": "uni-app"
      }
    }
  ],
  "tabBar": {
    "custom": true,
    "color": "#5F5F5F",
    "selectedColor": "#07c160",
    "borderStyle": "black",
    "backgroundColor": "#F7F7F7",
    "list": [
      {
        "pagePath": "pages/tabs/tab1",
        "text": "按钮1",
        "iconPath": "static/icon/icon-tab1.png",
        "selectedIconPath": "static/icon/icon-tab1-active.png"
      },
      {
        "pagePath": "pages/tabs/tab2",
        "text": "按钮2",
        "iconPath": "static/icon/icon-tab2.png",
        "selectedIconPath": "static/icon/icon-tab2-active.png"
      },
      {
        "pagePath": "pages/tabs/tab3",
        "text": "按钮3",
        "iconPath": "static/icon/icon-tab3.png",
        "selectedIconPath": "static/icon/icon-tab3-active.png"
      },
      {
        "pagePath": "pages/tabs/tab4",
        "text": "按钮4",
        "iconPath": "static/icon/icon-tab4.png",
        "selectedIconPath": "static/icon/icon-tab4-active.png"
      }
    ]
  }
}

引入`pinia`，创建`store`目录

在状态库中增加 roleId 参数，根据 roleId 参数判断角色权限

// src/store/index.ts
import {defineStore} from 'pinia'

const appStore = defineStore('app', {
  state: () => {
    return {
      roleId: '',
    }
  },
  actions: {
	setRoleId(id: string) {
      this.roleId = id
    },	
  }
 })

在main.ts中引入pinia

import { createSSRApp } from "vue";
import App from "./App.vue";

import uviewPlus from "uview-plus";
import * as Pinia from "pinia";

import "uno.css";

export function createApp() {
  const app = createSSRApp(App);

  app.use(Pinia.createPinia())
  app.use(uviewPlus)

  return {
    app,
    Pinia
  };
}

创建`tabData.ts`文件

import useAppStore from '@/store/index'

// tabBar的data
export const tabData = {
  selected: 0,
  //底部按钮高亮下标
  tabBar: {
    custom: true,
    color: '#5F5F5F',
    selectedColor: '#07c160',
    backgroundColor: '#F7F7F7',
    list: [] as any
  }
};

// roleId == '01' 显示的导航栏
const list1 = [
  {
    pagePath: 'pages/tabs/tab1',
    text: '首页',
    iconPath: '/static/icon/icon-tab1.png',
    selectedIconPath: '/static/icon/icon-tab1-active.png'
  },
  {
    pagePath: 'pages/tabs/tab2',
    text: '标签2',
    iconPath: '/static/icon/icon-tab2.png',
    selectedIconPath: '/static/icon/icon-tab2-active.png'
  },
  {
    pagePath: 'pages/tabs/tab3',
    text: '标签3',
    iconPath: '/static/icon/icon-tab3.png',
    selectedIconPath: '/static/icon/icon-tab3-active.png'
  },
  {
    pagePath: 'pages/tabs/tab4',
    text: '我的',
    iconPath: '/static/icon/icon-tab4.png',
    selectedIconPath: '/static/icon/icon-tab4-active.png'
  }
];

// roleId == '02' 显示的导航栏
const list2 = [
  {
    pagePath: 'pages/tabs/tab1',
    text: '推荐',
    iconPath: '/static/icon/icon-tab1.png',
    selectedIconPath: '/static/icon/icon-tab1-active.png'
  },
  {
    pagePath: 'pages/tabs/tab4',
    text: '我的',
    iconPath: '/static/icon/icon-tab4.png',
    selectedIconPath: '/static/icon/icon-tab4-active.png'
  }
];

// 更新菜单
export const updateRole = (that: any, type: string) => {
  //这里设置权限
  if (type === '01') {
    tabData.tabBar.list = list1;
  } else {
    tabData.tabBar.list = list2;
  }
  tabData.selected = 0;
  useAppStore().setRoleId(type)
  updateTab(that);
};

// 更新底部高亮
export const updateIndex = (that: any, index: number) => {
  tabData.selected = index;
  updateTab(that);
};

// 更新Tab状态
export const updateTab = (that: any) => {
  if ((typeof that.getTabBar === 'function') && that.getTabBar()) {
    that.getTabBar().setData(tabData);
  }
};

创建`tabs`目录，标签栏对应的页面

以tab4为例，其他的 tab 页类似，根据roleId渲染符合条件的组件

<!-- src/pages/tabs/tab4.vue -->
<template>
  <student-tab v-if="store.roleId === '01'" />
  <teacher-tab v-if="store.roleId === '02'" />
</template>

<script lang="ts" setup>
import { onShow } from '@dcloudio/uni-app'
import appStore from '@/store/index'
import { updateIndex } from '@/utils/tabData'

import TeacherTab from '../teacher/tabView4.vue'
import StudentTab from '../student/tabView4.vue'

const store = appStore();

onShow(() => {
  // 获取页面对象
  const page = getCurrentPages()[0]

  // 更新tabBar选中状态
  updateIndex(page, store.roleId === '02' ? 1 : 3);
})
</script>

<style lang="scss" scoped></style>

创建标签页对应的组件

以下只是示例，增加了一个切换角色的按钮

<!-- src/pages/student/tabView1.vue -->
<template>
  <!-- 状态栏占位 -->
  <view class="status-bar"></view>

  <view class="m-20">tabView1</view>

  <view class="m-20">
    <up-button type="primary" text="切换角色" @click="changeRole"></up-button>
  </view>
</template>

<script lang="ts" setup>
import { updateRole } from "@/utils/tabData";

const changeRole = () => {
  const page = getCurrentPages()[0]
  updateRole(page, "02")
}
</script>

<style lang="scss" scoped></style>

在`App.vue`中初始化

<!-- src/App.vue -->
<script lang="ts" setup>
import { updateRole } from '@/utils/tabData'
import { onLaunch } from '@dcloudio/uni-app'

onLaunch(() => {
	updateRole({}, '01')
})
</script>