微信小程序 实现列表项滑动显示删除按钮的功能

<view class="container">
 <view class="record-box" data-datetime="{{record.datetime}}" wx:for="{{detailList}}" wx:for-item="record">
  <view class="record" style="left:{{record.offsetX}}px" bindtouchstart="recordStart" catchtouchmove="recordMove" bindtouchend="recordEnd">
   <view class="left">
    <view>{{record.type}} {{record.count+record.unit}}</view>
    <view class="summary">{{record.remark}}</view>
   </view>
   <view class="right">
    {{record.datetime}}
   </view>
  </view>
  <view class="delete-box">
   <view>删除</view>
  </view>
 </view>
</view>

@import "../mon/weui.wxss";
 
.container {
 box-sizing: border-box;
 padding: 0 0 0 0;
}
 
 
 
.record {
 display: flex;
 flex-direction: row;
 align-items: center;
 width:100%;
  height: 120rpx;
 position: absolute;
 justify-content: space-between;
 background-color: #fff;
}
 
.record .right{
 margin-right: 30rpx;
   color: #888888;
}
.record .left{
 margin-left: 30rpx;
  display: flex;
  flex-direction: column;
 justify-content: space-between;
}
 
.record .left .summary{
  color: #aaa;
 font-size: 30rpx;
 line-height: 30rpx;
 
}
 
.record-box{
 height: 120rpx;
 width: 100%;
 border-bottom: 1rpx solid #ddd;
 background-color: #fff;
}
 
.delete-box{
 background-color: #e64340;
 color: #ffffff;
 float: right;
 height: 100%;
 width: 80px;
 display: flex;
 align-items: center;
 justify-content: center;
}
 
.record-box:last-child {
 border-bottom: 0;
}
 
.record .r-item {
  
}
　　

var detailList = [
  { datetime: '2017-01-01 17:00', count: 100, unit: 'ml', type: '开水', remark: '哈哈哈哈' },
  { datetime: '2017-01-01 17:01', count: 100, unit: 'ml', type: '开水' },
  { datetime: '2017-01-01 17:02', count: 100, unit: 'ml', type: '开水' }
];
var recordStartX = 0;
var currentOffsetX = 0;
Page(
  {
    data: {
      detailList: detailList
    }
    ,
    recordStart: function (e) {
      recordStartX = e.touches[0].clientX;
      currentOffsetX = this.data.detailList[0].offsetX;
      console.log('start x ', recordStartX);
    }
    ,
    recordMove: function (e) {
      var detailList = this.data.detailList;
      var item = detailList[0];
      var x = e.touches[0].clientX;
      var mx = recordStartX - x;
      console.log('move x ', mx);

      var result = currentOffsetX - mx;
      if (result >= -80 && result <= 0) {
        item.offsetX = result;
      }
      this.setData({
        detailList: detailList
      });
    }
    ,
    recordEnd: function (e) {
      var detailList = this.data.detailList;
      var item = detailList[0];
      console.log('end x ', item.offsetX);

      if (item.offsetX < -40) {
        item.offsetX = -80;

      } else {
        item.offsetX = 0;

      }
      this.setData({
        detailList: detailList
      });
    }

  }
);