微信小程序实现可长按移动控件

Page({
 /
  页面的初始数据
 /
 data: {
 //浮动按钮坐标
 flow_y: 130,
 flow_x: 20,

 pre_y:0,
 pre_x:0,
 //标记移动
 moveFlag: false,
 //标记控件是否可放置
 canNotPlace: false,
 imgSrc:"",
 },


 //长按按钮移动控件
 longPress: function (e) {
 console.log(e)
 this.setData({
 moveFlag: true,
 pre_x:e.touches[0].clientX,
 pre_y:e.touches[0].clientY,
 })
 // console.log(e)
 console.log("begin:(", this.data.flow_x, this.data.flow_y, ")")
 // this.setData({
 // flow_x: 1334-e.touches[0].pageX, // 获取触摸时的原点
 // flow_y: 750-e.touches[0].pageY,
 // })
 //console.log(startX)

 },

 // 触摸结束事件
 touchEnd: function (e) {
 this.setData({
 moveFlag: false
 })

 // console.log("flow:(", this.data.flow_x, this.data.flow_y, ")")
 //监测按钮放置区域
 if (!((this.data.flow_x < 730) && (this.data.flow_x > 20))&&((this.data.flow_y < 1150) && (this.data.flow_y > 130))) {
 this.setData({
 flow_x: 20, // 转换rpx
 flow_y: 130,
 })
 }
 // this.setData({
 // flow_x: 20, // 转换rpx
 // })
 },

 touchMove: function (e) {
 //根据move差值动态布局
 if (this.data.moveFlag) {
 // console.log("page:(", e.touches[0].pageX, e.touches[0].pageY, ")")
 // console.log(move_x,move_y)

 var x =this.data.flow_x -(e.touches[0].clientX-this.data.pre_x)2
 var y =this.data.flow_y -(e.touches[0].clientY-this.data.pre_y)2
 this.setData({
 flow_x: x, // 转换rpx
 flow_y: y,
 })
 // console.log(x,y)
 // this.setData({
 // flow_x: x, // 转换rpx
 // flow_y: y,
 // })
 if (!(((x < 730) && (x > 20))&&((y < 1000) && (y > 130)))) {
 this.setData({
  canNotPlace: true,
 })
 } else {
 this.setData({
  canNotPlace: false,
 })
 }
 this.setData({
 pre_x:e.touches[0].clientX,
 pre_y:e.touches[0].clientY,
 })
 }
 },


 catchtouchmove: function () {
 //防止蒙层触摸穿透
 },



 /
  生命周期函数--监听页面加载
 /
 onLoad: function (options) {

 },

 /
  生命周期函数--监听页面初次渲染完成
 /
 onReady: function () {
 wx.hideLoading()
 },

 /
  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
 /
 onUnload: function () {

 },

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

 /
  页面上拉触底事件的处理函数
 /
 onReachBottom: function () {

 },

 /
  用户点击右上角分享
 /
 onShareAppMessage: function () {

 }
})

.follow_icon{
 position: fixed;
 / margin: 0 10rpx; /
 width:70rpx;
 height:70rpx;
 bottom: var(--flow_y--);
 right: var(--flow_x--);
 z-index: 1001;
}

/mask/
.drawer_screen {
 width: 100%;
 height: 100%;
 position: fixed;
 : 0;
 left: 0;
 z-index: 5;
 background: #000;
 opacity: 0.5;
 overflow: hidden;
}

<!-- 刷新按钮 -->
<!-- <view bindtap='getArticle' style="opacity:0.8"> -->
<view catchtouchmove="catchtouchmove" ><image bindtap='getArticle' bindlongpress="longPress" bindtouchmove='touchMove' bindtouchend="touchEnd" style="--flow_y--:{{flow_y}}rpx;--flow_x--:{{flow_x}}rpx;" class="follow_icon" src="{{imgSrc}}"></image></view>

<!-- 蒙版屏蔽，防止触控穿透 -->
<view style="{{!canNotPlace?'background: #777;':'background: #b81e1e;'}}" catchtouchmove="catchtouchmove" class="drawer_screen" data-statu="open" wx:if="{{moveFlag}}"></view> 
<!-- </view> -->