vue手势解决方案

1、需求

　　因为项目中要做一个可以移动、旋转和放缩具有合成图片的功能，例如：

剑可以随意移动，然后把位移、旋转角度和放缩值传给后台进行合成。

2、解决方案

网上搜到手势插件AlloyFinger，https://github.com/AlloyTeam/AlloyFinger

首先安装AlloyFinger：npm install alloyfinger

然后在Vue文件里面引用：import AlloyFinger from 'alloyfinger'

使用方法：

mounted() {
      this.getData();
      this.requireList = document.getElementsByClassName('required');
      let swordEle = document.getElementsByClassName('swordPic')[0];
      let bwidth, bheight, swidth, sheight;
      Transform(swordEle);
      var initScale = 1;
      var af = new AlloyFinger(swordEle, {
        touchStart: function () {
          console.log('touchStart')
        },
        touchMove: function (evt) {
          swordEle.style.translateX += evt.deltaX;
          swordEle.style.translateY += evt.deltaY;
          evt.preventDefault();
        },
        touchEnd: function () {
          console.log('end')
          console.log(swordEle.style.transform)
        },
        touchCancel: function () {
          console.log('cancel')
        },
        multipointStart: function () {
          initScale = swordEle.scaleX;
        },
        multipointEnd: function () {
        },
        tap: function () {
        },
        doubleTap: function () {
        },
        longTap: function () {
        },
        singleTap: function () {
        },
        rotate: function (evt) {
          swordEle.rotateZ += evt.angle;
        },
        pinch: function (evt) {
          swordEle.scaleX = swordEle.scaleY = initScale * evt.scale;
        },
        pressMove: function (evt) {
          let widthDiff = bwidth - swidth;
          let heightDiff = bheight - sheight;
          console.log('diff' + widthDiff + ' ' + heightDiff)
          console.log('translateX:' + swordEle.translateX  + '' + swordEle.translateY )
          if (((evt.deltaX>0)&&(swordEle.translateX >= widthDiff))||((evt.deltaY>0)&&(swordEle.translateY >= heightDiff))||((swordEle.translateX<0)&&((evt.deltaX<0)))||((swordEle.translateY<0)&&((evt.deltaY<0)))) {
            console.log('越界')
          } else {
            swordEle.translateX += evt.deltaX;
            swordEle.translateY += evt.deltaY;
          }

          console.log('pressmve:' + swordEle.translateX)
          console.log('pressmve:' + swordEle.translateY)
        },
        swipe: function (evt) {
//          console.log("swipe" + evt.direction);
        }
      });
      document.getElementById('coverPic').onload = function () {
        bwidth = this.width;
        bheight = this.height;
        console.log(bwidth + ' ' + bheight)
        if (document.body.scrollHeight - document.body.clientHeight > 20) {
          document.body.scrollTop = document.body.scrollHeight;
        }
      }
      document.getElementById('swordEle').onload = function () {
        swidth = this.width;
        sheight = this.height;
        console.log(swidth + ' ' + sheight)
      }
    },