cover-view 里button 不显示

1,开发者工具正常，真机上不显示按钮

    <cover-view wx:else>

      <cover-view class=“pick_avantar pick_share_margin”>

        <cover-image class=“pick_avantar_img” src=“”></cover-image>

      </cover-view>

      <cover-view class=“pick_info2”>

        <cover-view class=“pick_info_name”>赵丽颖</cover-view>

        <cover-view class=“pick_info_text”>快分享好友为爱豆助力</cover-view>

      </cover-view>

      <cover-view class=“pick_button2”>

        <button class=“share_button” open-type=“share”></button>

      </cover-view>

    </cover-view>