微信小程序左滑刪除功能

wxml:

<view class="container">
 <view class="touch-item {{item.isTouchMove ? 'touch-move-active' : ''}}" data-index="{{index}}" bindtouchstart="touchstart" bindtouchmove="touchmove" wx:for="{{items}}" wx:key="">
  <view class="content">{{item.content}}</view>
  <view class="del" catchtap="del" data-index="{{index}}">刪除</view>
 </view>
</view>

wxss:

.container{
  width:100%;
  overflow: hidden;
  box-sizing: border-box;
  padding-bottom:10rpx;
}
.touch-item {
 font-size: 14px;
 display: flex;
 /* //均勻排布每個元素 */
 justify-content: space-between;
 border-bottom:1px solid #ccc;
 width: 100%;
 overflow: hidden;
}
.content {
 width: 100%;
 padding: 10px;
 line-height: 22px;
 margin-right:0;
 -webkit-transition: all 0.4s;
 transition: all 0.4s;
 -webkit-transform: translateX(90px);
 transform: translateX(90px);
 margin-left: -90px;
}
.del {
 background-color: #c00;
 width: 90px;
 display: flex;
 flex-direction: column;
 align-items: center;
 justify-content: center;
 color: #fff;
 -webkit-transform: translateX(90px);
 transform: translateX(90px);
 -webkit-transition: all 0.4s;
 transition: all 0.4s;
}
.touch-move-active .content,
.touch-move-active .del {
 -webkit-transform: translateX(0);
 transform: translateX(0);
}

js:

Page({
  data: {
    items: [
      {
        content:'測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動',
      },
      {
        content: '測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動',
      },
      {
        content: '測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動',
      },
      {
        content: '測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動',
      },
      {
        content: '測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動,測試向左滑動',
      },
    ],
    startX: 0, //開始坐標
    startY: 0
  },
  // onLoad: function () {
  //   // 可以在數組中直接寫入數據,也可以在onload的函數中加載進去
  //   for (var i = 0; i < 10; i++) {
  //     this.data.items.push({
  //       content: i + " 向左滑動刪除哦,向左滑動刪除哦,向左滑動刪除哦,向左滑動刪除哦,向左滑動刪除哦",
  //       isTouchMove: false //默認全隱藏刪除
  //     })
  //   }
  //   this.setData({
  //     items: this.data.items
  //   })
  // },
  //手指觸摸動作開始 記錄起點X坐標
  touchstart: function (e) {
    //開始觸摸時 重置所有刪除
    this.data.items.forEach(function (v, i) {
      if (v.isTouchMove)//只操作為true的
        v.isTouchMove = false;
    })
    this.setData({
      startX: e.changedTouches[0].clientX,
      startY: e.changedTouches[0].clientY,
      items: this.data.items
    })
  },
  //滑動事件處理
  touchmove: function (e) {
    var that = this,
      index = e.currentTarget.dataset.index,//當前索引
      startX = that.data.startX,//開始X坐標
      startY = that.data.startY,//開始Y坐標
      touchMoveX = e.changedTouches[0].clientX,//滑動變化坐標
      touchMoveY = e.changedTouches[0].clientY,//滑動變化坐標
      //獲取滑動角度
      angle = that.angle({ X: startX, Y: startY }, { X: touchMoveX, Y: touchMoveY });
    that.data.items.forEach(function (v, i) {
      v.isTouchMove = false
      //滑動超過30度角 return
      if (Math.abs(angle) > 30) return;
      if (i == index) {
        if (touchMoveX > startX) //右滑
          v.isTouchMove = false
        else //左滑
          v.isTouchMove = true
      }
    })
    //更新數據
    that.setData({
      items: that.data.items
    })
  },
  /**
   * 計算滑動角度
   * @param {Object} start 起點坐標
   * @param {Object} end 終點坐標
   */
  angle: function (start, end) {
    var _X = end.X - start.X,
      _Y = end.Y - start.Y
    //返回角度 /Math.atan()返回數字的反正切值
    return 360 * Math.atan(_Y / _X) / (2 * Math.PI);
  },
  //刪除事件
  del: function (e) {
    this.data.items.splice(e.currentTarget.dataset.index, 1)
    this.setData({
      items: this.data.items
    })
  }
})