vue实现拖拽效果

1、封装拖拽组件

<template>
  <div @touchstart="down" @touchmove="move" @touchend="end" id="circlebox" class="circle" @click="goHome">
  </div>
</template>
<script>
export default {
  data() {
    return {
      positionX: 0,
      positionY: 0,
      innerHeight: 0,
      innerWidth: 0,
    };
  },
  methods: {
    // 返回首页
    goHome() {
      console.log('返回首页');
    },
    /* 阻止移动端屏幕默认滑动 */
    default(e) {
      let divv = document.getElementById('circlebox');
      divv.addEventListener(
        'touchmove',
        function (e) {
          e.preventDefault();
        },
        { passive: false }
      );
    },
    getThisNode() {
      let odiv = document.getElementById('circlebox');
      // console.log(this.positionX, this.positionY);
      if (this.positionX <= 0) {
        this.positionX = 0;
      } else if (this.positionX >= this.innerWidth) {
        this.positionX = this.innerWidth;
      } else {
        this.positionX = this.positionX;
      }
      if (this.positionY <= 0) {
        this.positionY = 0;
      } else if (this.positionY >= this.innerHeight) {
        this.positionY = this.innerHeight;
      } else {
        this.positionY = this.positionY;
      }
      // if (this.positionX <= 20) {
      //   this.positionX = 20;
      // } else if (this.positionX >= this.innerWidth - 20) {
      //   this.positionX = this.innerWidth - 20;
      // } else {
      //   this.positionX = this.positionX;
      // }
      // if (this.positionY <= 20) {
      //   this.positionY = 20;
      // } else if (this.positionY >= this.innerHeight - 20) {
      //   this.positionY = this.innerHeight - 20;
      // } else {
      //   this.positionY = this.positionY;
      // }
      odiv.style.left = `${this.positionX - 20}px`;
      odiv.style.top = `${this.positionY - 20}px`;
    },
    // 光标按下
    down(e) {
      this.default();
      this.innerHeight = e.view.innerHeight;
      this.innerWidth = e.view.innerWidth;
      this.positionX = e.changedTouches[0].pageX;
      this.positionY = e.changedTouches[0].pageY;
    },
    // 光标移动
    move(e) {
      this.getThisNode();
      this.default();
      this.positionX = e.changedTouches[0].pageX;
      this.positionY = e.changedTouches[0].pageY;
      this.getThisNode();
    },
    // 光标抬起
    end(e) {
      // console.log('end');
    }
  }
};
</script>
<style lang="less" scoped>
.circle{
  display: block;
  position: fixed;
  z-index: 999;
  touch-action: none;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: red;
  right: -20px;
  top: 60%;
  img{
    width: 100%;
    height: 100%;
  }
}
</style>

2、需要使用的页面中页面组件

import homeIcon from '@/components/drag/homeIcon';

 components: {
    'homeIcon': homeIcon,
  }