使用自定义的CustomCallout后,在slot="callout"的子组件里绑定点击事件没有用，只能执行系统带的bindcallouttap事件。

<map
      id="myMap"
      style="width: 100%; height: 300px;"
      latitude="{{latitude}}"
      longitude="{{longitude}}"
      bindmarkertap="markertap"
      bindcallouttap="callouttap"
      bindlabeltap="labeltap"
      markers="{{markers}}"
      scale="16"
    >
      <cover-view slot="callout">
        <block wx:for="{{customCalloutMarkerIds}}" wx:key="*this">
            <cover-view  class="customCallout" marker-id="{{item}}" catchtap="handleTap">
              <cover-image class="icon" src="/image/voice.png"></cover-image>
              <cover-view class="content"> 
              {{num}}-{{item}}-{{index}}
            </cover-view>
          </cover-view>
        </block>
      </cover-view>
    </map>