微信小程序实现左滑修改、删除功能

<view class=\"offer-item\" wx:for-items=\'{{offerList}}\'>
  <!--这里绑定了刚才说的3个函数分别为 touchS，touchM touchE-->
  <!--这里注意这个 style=\"{{item.txtStyle}}\" ，这是我们一会再js中 将要设置的样式 -->
  <view style=\"{{item.txtStyle}}\">
   <view class=\"offer-item-top fl clearfix\" bindtouchstart=\"touchS\" bindtouchmove=\"touchM\" bindtouchend=\"touchE\" data-index=\"{{index}}\">
    <navigator bindtap=\'navigatorTo\' data-index=\"{{item.id}}\">
     <view class=\'content\'>
      <view class=\'  clearfix\'>
       <view class=\'fl\'>
        {{item. }}党建项目报价表
       </view>
       <image src=\'../../images/right.png\' class=\'fr\'></image>
      </view>
      <view class=\'note clearfix\'>
       <view class=\'price fl\'>
        {{item.create_time}}
       </view>
      </view>
     </view>
    </navigator>
   </view>

   <!--这里是左滑按钮部分----start-->
   <view bindtap=\"delItem\" class=\'posit fr isMove\' hidden=\'{{!item.isMove}}\'>
     <view class=\"ref\" data-offerid=\"{{item.id}}\" data-index=\"{{item.id}}\" catchtap=\"ref\">
      <image src=\'../../images/ref.png\'></image>
     </view>
     <view class=\"del\" data-offerid=\"{{item.id}}\" data-index=\"{{item.id}}\" catchtap=\"del\">
      <image src=\'../../images/default.png\'></image>
     </view>
   </view>
   <!--这里是左滑按钮部分----end-->
  </view>
</view>

.offer-item {
 height: 150rpx;
 width: 100vw;
 overflow-x: hidden;
 border-bottom: 1px solid #f0f0f0;
}

.offer-item>view {
 position: absolute;
 /* width: calc(100% + 200rpx); */
 height: 150rpx; 
}

.offer-item .offer-item-top {
 height: 100%;
}

.offer-item .offer-item-top navigator {
 display: inline-block;
 width: 100vw; 
 height: 100%;
}

.offer-item .content {
 padding: 35rpx 30rpx;
 position: relative;
 height: calc(100% - 70rpx);
}

.offer-item .  .fl {
 display: inline-block;
 width: 78%;
 overflow: hidden;
 text-overflow: ellipsis;
 white-space: nowrap;
 font-size: 30rpx;
 color: #333;
}

.offer-item .  .fr {
 display: inline-block;
 width: 20rpx;
 height: 26rpx;
 margin-top: 5rpx;
}

.offer-item .note {
 position: absolute;
 left: 30rpx;
 bottom: 35rpx;
 width: calc(100vw - 60rpx);
 font-size: 24rpx;
 color: #999;
}

.offer-item .posit {
 width: 200rpx;
 height: 150rpx;
 line-height: 150rpx;
 text-align: center;
 display: none
}

.posit.isMove {
 display: inline-block;
 position: absolute;
}

.posit.isMove[hidden] {
 display: none
}

.offer-item .posit>view {
 display: inline-block;
 width: 100rpx;
}

.offer-item .posit>view:first-of-type {
 background-color: #FED847;
}

.offer-item .posit>view:last-of-type {
 background-color: #C71B1B;
}

.offer-item .posit image {
 display: inline-block;
 width: 36rpx;
 height: 36rpx;
}

let len = 0;     // 初次加载长度
let hadLastPage = false; // 判断是否到最后一页

var initdata = function (that) {
 var list = that.data.offerList
 for (var i = 0; i < list.length; i++) {
  list[i].txtStyle = \"\";
  list[i].isMove = false;
 }
 that.setData({ 
  offerList: list
 })
}

Page({
 data: {
  offerList: [

  ],
  delBtnWidth: 100,   // 删除按钮宽度单位（rpx）
 },


 // 手指刚放到屏幕触发
 touchS: function (e) {
  console.log(\"touchS\" + e);
  // initdata(this);
  // 判断是否只有一个触摸点
  if (e.touches.length == 1) {
   this.setData({
    // 记录触摸起始位置的X坐标
    startX: e.touches[0].clientX
   });
  };
  return false;
 },

 // 触摸时触发，手指在屏幕上每移动一次，触发一次
 touchM: function (e) {
  var that = this;
  initdata(that);
  if (e.touches.length == 1) {
   // 记录触摸点位置的X坐标
   var moveX = e.touches[0].clientX;
   // 计算手指起始点的X坐标与当前触摸点的X坐标的差值
   var disX = that.data.startX - moveX;
   // delBtnWidth 为右侧按钮区域的宽度
   var delBtnWidth = that.data.delBtnWidth;
   var txtStyle = \"\";
   if (disX == 0 || disX < 0) {   // 如果移动距离小于等于0，文本层位置不变
    txtStyle = \"left:0px\";
   } else if (disX > 0) {      // 移动距离大于0，文本层left值等于手指移动距离
    txtStyle = \"left:-\" + disX + \"px\";
    if (disX >= delBtnWidth) {
     // 控制手指移动距离最大值为删除按钮的宽度
     txtStyle = \"left:-\" + delBtnWidth + \"px\";
    }
   }
   // 获取手指触摸的是哪一个item
   var index = e.currentTarget.dataset.index;
   var list = that.data.offerList;
   // 将拼接好的样式设置到当前item中
   list[index].txtStyle = txtStyle;

   list[index].isMove = true;
   // 更新列表的状态
   this.setData({
    offerList: list
   });
  }
 },
 touchE: function (e) {
  console.log( e);
  var that = this
  if (e.changedTouches.length == 1) {
   // 手指移动结束后触摸点位置的X坐标
   var endX = e.changedTouches[0].clientX;
   // 触摸开始与结束，手指移动的距离
   var disX = that.data.startX - endX;
   var delBtnWidth = that.data.delBtnWidth;
   // 如果距离小于删除按钮的1/2，不显示删除按钮
   var txtStyle = disX > delBtnWidth / 2 ? \"left:-\" + delBtnWidth + \"px\" : \"left:0px\";
   // 获取手指触摸的是哪一项
   var index = e.currentTarget.dataset.index;
   var list = that.data.offerList;
   list[index].txtStyle = txtStyle;
   // 更新列表的状态
   that.setData({
    offerList: list
   });
  }
 },

 /**
  * 
  */
 navigatorTo: function (event) {

 },

 /**
  * 删除操作
  */
 del: function (e) {
  var that = this;
  var data = {
   id: e.currentTarget.dataset.index
  };
  wx.showModal({
    : \'\',
   content: \'确定选择删除么？\',
   confirmColor: \'#C71B1B\',
   cancelColor: \'#666666\',
   success: function (res) {
    if (res.confirm) {
     utils.requestFun(\"接口url\", data, \'POST\', function (msg) {
      console.log(msg)

      wx.showToast({
        : \'删除成功\',
       icon: \'success\',
       duration: 1500
      })
      var lists = that.data.offerList;
      var list1 = [];
      for (let i = 0; i < lists.length; i++) {
       if (lists[i].id != e.currentTarget.dataset.index) {
        list1.push(lists[i])
       }
      }
      len--;
      that.setData({
       offerList: list1
      })
     })
    } else if (res.cancel) {

    }
   }
  })
 },

 /**
  * 修改操作
  */
 ref: function (e) {
  wx.navigateTo({
   url: \'修改页面路径?id=\' + e.currentTarget.dataset.index,
  })
 },

 /**
  * 生命周期函数--监听页面加载
  */
  : function (options) {
  page = 0;
  this.loadList();
 },


 /**
  * 生命周期函数--监听页面初次渲染完成
  */
 onReady: function () {

 },

 /**
  * 生命周期函数--监听页面显示
  */
 onShow: function () {

 },

 /**
  * 生命周期函数--监听页面隐藏
  */
 onHide: function () {

 },

 /**
  * 生命周期函数--监听页面卸载
  */
  : function () {
   hadLastPage = false;
   len = 0; 
 },

 /**
  * 页面相关事件处理函数--监听用户下拉动作
  */
 onPullDownRefresh: function () {

 },

 /**
  * 页面上拉触底事件的处理函数
  */
 onReachBottom: function (event) {
  console.log(\"上拉事件\")
  this.loadList();
 }, 

 /** 
  * 数据请求封装
  */
 loadList: function (event) {
  if (hadLastPage != false) {
   wx.showToast({
     : \'到底啦\',
   });
   return;
  }
  var that = this;
  // 显示加载图标 
  wx.showLoading({
    : \'玩命加载中\',
  })

  let data = {
    length: len,
    openId: \'openid\'
  };
  utils.requestFun(\"接口url\", data, \'POST\', function (msg) {

   if (msg.data.length != 0) {
    var lists = that.data.offerList;
    for (let i = 0; i < msg.data.length; i++) {
     msg.data[i].isMove = false;
     lists.push(msg.data[i]);
    }

    // len 
    len = len + msg.data.length;

    // 设置数据 
    that.setData({
     offerList: lists
    })
   } else {
    hadLastPage = true;
   }
   wx.hideLoading();
  })
 }

})