Mini-Program/custom-tab-bar/index.wxml

<view class="tab-bar" wx:if="{{show}}">
  <!-- 左侧按钮组 -->
  <view class="tab-bar-left">
    <view class="tab-bar-item {{selected === 'index' ? 'active' : ''}}" 
          data-path="pages/index/index" 
          data-key="index" 
          bindtap="switchTab">
      <view class="tab-bar-icon">
        <view class="tab-bar-badge" wx:if="{{badges['index']}}">{{badges['index']}}</view>
      </view>
      <view class="tab-bar-text">首页</view>
    </view>
    
    <view class="tab-bar-item {{selected === 'buyer' ? 'active' : ''}}" 
          data-path="pages/buyer/index" 
          data-key="buyer" 
          bindtap="switchTab">
      <view class="tab-bar-icon">
        <view class="tab-bar-badge" wx:if="{{badges['buyer']}}">{{badges['buyer']}}</view>
      </view>
      <view class="tab-bar-text">买蛋</view>
    </view>
  </view>
  
  <!-- 鸡蛋估价按钮 -->
  <view class="tab-bar-center" bindtap="goToEvaluatePage">
    <view class="egg-button">
      <view class="egg-icon">🥚</view>
      <view class="egg-text">估</view>
    </view>
  </view>
  
  <!-- 右侧按钮组 -->
  <view class="tab-bar-right">
    <view class="tab-bar-item {{selected === 'seller' ? 'active' : ''}}" 
          data-path="pages/seller/index" 
          data-key="seller" 
          bindtap="switchTab">
      <view class="tab-bar-icon">
        <view class="tab-bar-badge" wx:if="{{badges['seller']}}">{{badges['seller']}}</view>
      </view>
      <view class="tab-bar-text">卖蛋</view>
    </view>
    
    <view class="tab-bar-item {{selected === 'profile' ? 'active' : ''}}" 
          data-path="pages/profile/index" 
          data-key="profile" 
          bindtap="switchTab">
      <view class="tab-bar-icon">
        <view class="tab-bar-badge" wx:if="{{badges['profile']}}">{{badges['profile']}}</view>
      </view>
      <view class="tab-bar-text">我</view>
    </view>
  </view>
</view>