<!-- 下拉框 -->    <view class='select_box'>      <view class='select' catchtap='selectTap'>        <text class='select_text'>{{selectData[index]}}</text>        <image class='words_img' src='../../images/dv.png'></image>        <image class='select_img {{show&&"select_img_rotate"}}' src='/image/gobottom.png'></image>      </view>      <view class='option_box' style='height:{{show?(selectData.length>5?300:selectData.length*60):0}}rpx;'>        <text class='option' style='{{index==selectData.length-1&&"border:0;"}}' wx:for='{{selectData}}' wx:key='this' data-index='{{index}}' catchtap='optionTap'>{{item}}</text>      </view>    </view>

data{  show: false, //控制下拉列表的显示隐藏，false隐藏、true显示    selectData: ['消费账户', '平台返利账户', '微信钱包'], //下拉列表的数据    index: 0, //选择的下拉列 表下标,}  // 点击下拉显示框  selectTap() {    this.setData({      show: !this.data.show,    });  },  // 点击下拉列表  optionTap(e) {    let Index = e.currentTarget.dataset.index; //获取点击的下拉列表的下标    this.setData({      index: Index,      show: !this.data.show    });  },

.select_box {  background: #fff;  width: 620rpx;  margin: 0 auto;  margin-top: 40rpx;  height: 86rpx;  line-height: 86rpx;  text-align: left;  position: relative;}.select {  box-sizing: border-box;  width: 100%;  height: 86rpx;  border: 1px solid #efefef;  border-radius: 8rpx;  display: flex;  align-items: center;  padding: 0 20rpx;}.select_text {  font-size: 28rpx;  flex: 1;  color: rgb(102, 102, 102);  line-height: 86rpx;  height: 86rpx;}.select_img {  width: 40rpx;  height: 40rpx;  display: block;  transition: transform 0.3s;}.select_img_rotate {  transform: rotate(180deg);}.option_box {  position: absolute;  top: 86rpx;  width: 100%;  border: 1px solid #efefef;  box-sizing: border-box;  height: 0;  overflow-y: auto;  border-top: 0;  background: #fff;  transition: height 0.3s;}.option {  display: block;  line-height: 40rpx;  font-size: 28rpx;  border-bottom: 1px solid #efefef;  padding: 10rpx;  color: rgb(102, 102, 102);  font-size: 28rpx;}