<view bindtouchmove="touchmoveCallback" bindtouchstart="touchstartCallback"> <image src="../../images/123456.jpg" mode="aspecFit" style="width: {{ touch.scaleWidth }}rpx;height: {{ touch.scaleHeight }}rpx" bindload="bindload" direction="all" bindchange="onChange" bindscale="onScale" scale scale-min="0.5" scale-max="10" scale-value="2"></image> </view> Page({ data: { touch: { distance: 0, scale: 1, baseWidth: null, baseHeight: null, scaleWidth: null, scaleHeight: null } }, touchstartCallback: function (e) { // 单手指缩放开始,也不做任何处理 if (e.touches.length == 1) { console.log("单滑了") return } // 注意touchstartCallback 真正代码的开始 // 一开始我并没有这个回调函数,会出现缩小的时候有瞬间被放大过程的bug // 当两根手指放上去的时候,就将distance 初始化。 let xMove = e.touches[1].clientX - e.touches[0].clientX; let yMove = e.touches[1].clientY - e.touches[0].clientY; let distance = Math.sqrt(xMove * xMove + yMove * yMove); this.setData({ 'touch.distance': distance, }) }, touchmoveCallback: function (e) { let touch = this.data.touch if (e.touches.length == 1) { console.log("单滑了"); return } // 单手指缩放我们不做任何操作 if(e.touches.length == 1) return console.log('双手指运动') let xMove = e.touches[1].clientX - e.touches[0].clientX; let yMove = e.touches[1].clientY - e.touches[0].clientY; // 新的 ditance let distance = Math.sqrt(xMove * xMove + yMove * yMove); let distanceDiff = distance - touch.distance; let newScale = touch.scale + 0.005 * distanceDiff // 为了防止缩放得太大,所以scale需要限制,同理最小值也是 if(newScale >= 2) { newScale = 2 } if(newScale <= 0.6) { newScale = 0.6 } let scaleWidth = newScale * touch.baseWidth let scaleHeight = newScale * touch.baseHeight // 赋值 新的 => 旧的 this.setData({ 'touch.distance': distance, 'touch.scale': newScale, 'touch.scaleWidth': scaleWidth, 'touch.scaleHeight': scaleHeight, 'touch.diff': distanceDiff }) }, bindload: function(e) { // bindload 这个api是<image>组件的api类似<img>的onload属性 this.setData({ 'touch.baseWidth': e.detail.width, 'touch.baseHeight': e.detail.height, 'touch.scaleWidth': e.detail.width, 'touch.scaleHeight': e.detail.height }) } }) 为啥我的在苹果手机放大后可以移动, 安卓放大后不能移动
cover-image加载得图片不能在安卓手机上滑动cover-image加载得图片不能在安卓手机上滑动,在苹果手机上可以
2019-11-07