vuejs移动端实现div拖拽移动

<template>
 <div id="webId">
 <div>你的web页面</div>
 <!-- 1.1 如果碰到滑动问题，请检查这里是否属于同一点。 -->
 <!-- 悬浮的HTML -->
 <div v-if="!isShow" class="xuanfu" id="moveDiv"
 @mousedown="down" @touchstart="down"
 @mousemove="move" @touchmove="move"
 @mouseup="end" @touchend="end"
 >
 <div class="yuanqiu">
 {{pageInfo.totalPage}}
 </div>
 </div>
 </div>
</template>

<script>
data() {
 return {
 flags: false,
 position: { x: 0, y: 0 },
 nx: '', ny: '', dx: '', dy: '', xPum: '', yPum: '',
 }
}

methods: {
 // 实现移动端拖拽
 down(){
 this.flags = true;
 var touch;
 if(event.touches){
 touch = event.touches[0];
 }else {
 touch = event;
 }
 this.position.x = touch.clientX;
 this.position.y = touch.clientY;
 this.dx = moveDiv.offsetLeft;
 this.dy = moveDiv.offsetTop;
 },
 move(){
 if(this.flags){
 var touch ;
 if(event.touches){
 touch = event.touches[0];
 }else {
 touch = event;
 }
 this.nx = touch.clientX - this.position.x;
 this.ny = touch.clientY - this.position.y;
 this.xPum = this.dx+this.nx;
 this.yPum = this.dy+this.ny;
 moveDiv.style.left = this.xPum+"px";
 moveDiv.style.top = this.yPum +"px";
 //阻止页面的滑动默认事件
 document.addEventListener("touchmove",function(){ // 1.2 如果碰到滑动问题，请注意是否获取到 touchmove
 event.preventDefault();//jq 阻止冒泡事件
 // event.stopPropagation(); // 如果没有引入jq 就用 stopPropagation()
 },false);
 }
 },
//鼠标释放时候的函数
 end(){
 this.flags = false;
 },
}
</script>

<style>
 .xuanfu {
 height: 4.5rem;
 width: 4.5rem;
 /*1.3 如果碰到滑动问题，请检查 z-index。z-index需比web大一级*/
 z-index: 999;
 position: fixed;
 top: 4.2rem;
 right: 3.2rem;
 border-radius: 0.8rem;
 background-color: rgba(0, 0, 0, 0.55);
 }
 .yuanqiu {
 height: 2.7rem;
 width: 2.7rem;
 border: 0.3rem solid rgba(140, 136, 136, 0.5);
 margin: 0.65rem auto;
 color: #000000;
 font-size: 1.6rem;
 line-height: 2.7rem;
 text-align: center;
 border-radius: 100%;
 background-color: #ffffff;
 }
</style>