微信小程序实现左滑删除效果

<scroll-view scroll-y="{{isScroll}}" style='width:{{windowWidth}}px;height:{{windowHeight}}px'>
 <block wx:key="item" wx:for="{{data}}">
  <view data-index='{{index}}' class="custom_item" bindtouchstart="drawStart" bindtouchmove="drawMove" bindtouchend="drawEnd" style="right:{{item.right}}rpx">
  <view class="content">{{item.content}}</view>
  <view class="remove" bindtap="delItem">删除 </view>
  </view>
 </block>
 </scroll-view>

Page({
 data: {
 delBtnWidth: 160,
 data: [{ content: "采购", right: 0 }, { content: "供应", right: 0 }, { content: "采购", right: 0 }, { content: "供应", right: 0}],
 isScroll: true,
 windowWidth:0,
 windowHeight: 0,
 },
 onLoad: function (options) {
 var that = this;
 wx.getSystemInfo({
  success: function (res) {
  that.setData({
   windowWidth: res.windowWidth,
   windowHeight: res.windowHeight
  });
  }
 });
 },
 drawStart: function (e) {
 // console.log("drawStart"); 
 var touch = e.touches[0]

 for (var index in this.data.data) {
  var item = this.data.data[index]
  item.right = 0
 }
 this.setData({
  data: this.data.data,
  startX: touch.clientX,
 })

 },
 drawMove: function (e) {
 var touch = e.touches[0]
 var item = this.data.data[e.currentTarget.dataset.index]
 var disX = this.data.startX - touch.clientX

 if (disX >= 20) {
  if (disX > this.data.delBtnWidth) {
  disX = this.data.delBtnWidth
  }
  item.right = disX
  this.setData({
  isScroll: false,
  data: this.data.data
  })
 } else {
  item.right = 0
  this.setData({
  isScroll: true,
  data: this.data.data
  })
 }
 },
 drawEnd: function (e) {
 var item = this.data.data[e.currentTarget.dataset.index]
 if (item.right >= this.data.delBtnWidth / 2) {
  item.right = this.data.delBtnWidth
  this.setData({
  isScroll: true,
  data: this.data.data,
  })
 } else {
  item.right = 0
  this.setData({
  isScroll: true,
  data: this.data.data,
  })
 }
 },

 delItem: function (e) {

 }
})

.custom_item{
 height: 240rpx;
 width: 100%;
 display: flex;
 position: relative;
}
.remove{ 
 width: 160rpx; 
 height: 100%; 
 background-color: red; 
 color: white; 
 position: absolute; 
 top: 0; 
 right: -160rpx; 
 display: flex; 
 justify-content: center; 
 align-items: center; 
}