Swift - 各种手势检测大全（UIGestureRecognizer及其子类）
UIGestureRecognizer 有许多子类，用于监听一些常见的手势事件，这些子类主要有：
1、UISwipeGestureRecognizer：滑动（快速移动）
//滑动（快速移动）funcswipeGestureRecognizer(){letswipe=UISwipeGestureRecognizer(target:self,action:#selector(ViewController.swipe(_:)))swipe.direction=.up//监听方向self.view.addGestureRecognizer(swipe)}@objcfuncswipe(_recognizer:UISwipeGestureRecognizer){print("swipe ok")letpoint=recognizer.location(in:self.view)//这个点是滑动的起点print(point.x)print(point.y)}
注意1：如果 UISwipeGestureRecognizer 在不指定方向的时候，默认向右滑动才会触发事件。如果要指定方向，需要设置 direction 属性
swipe.direction=.up//监听方向
注意2：有网友问如果各个方向都要响应怎么办，只要多定义几个 UISwipeGestureRecognizer 就可以了
//滑动（快速移动）funcswipeGestureRecognizer(){letswipeUp=UISwipeGestureRecognizer(target:self,action:#selector(ViewController.swipe(_:)))swipeUp.direction=.upself.view.addGestureRecognizer(swipeUp)letswipeDown=UISwipeGestureRecognizer(target:self,action:#selector(ViewController.swipe(_:)))swipeDown.direction=.downself.view.addGestureRecognizer(swipeDown)}@objcfuncswipe(_recognizer:UISwipeGestureRecognizer){ifrecognizer.direction==.up{print("向上滑动")}elseifrecognizer.direction==.down{print("向下滑动")}letpoint=recognizer.location(in:self.view)//这个点是滑动的起点print(point.x)print(point.y)}
2、UIScreenEdgePanGestureRecognizer：边缘滑动
（1）这个是 UISwipeGestureRecognizer 的子类，与后者不同的时。UIScreenEdgePanGestureRecognizer 只触发从边缘开始的划动操作，比如从左侧边缘开始向右滑动。
（2）UIScreenEdgePanGestureRecognizer 没有 direction 属性，增加了个 edges 属性。表示要响应哪个边缘的划动操作。可以是从左边缘向右滑动，或右边缘向左、上边缘向下、下边缘向上、或响应全部边缘滑动。
// 边缘滑动funcscreenEdgePanGestureRecognizer(){letswipe=UIScreenEdgePanGestureRecognizer(target:self,action:#selector(screenEdgePanSwipe))swipe.edges=UIRectEdge.left//从左边缘开始滑动self.view.addGestureRecognizer(swipe)}@objcfuncscreenEdgePanSwipe(_recognizer:UIScreenEdgePanGestureRecognizer){print("left edgeswipe ok")letpoint=recognizer.location(in:self.view)//这个点是滑动的起点print(point.x)print(point.y)}
3、UITapGestureRecognizer：轻点手势（点击）
（1）可以通过 numberOfTouchesRequired 属性设置触摸点数，比如设置 2 表示必须两个手指触摸时才会触发
（2）通过 numberOfTapsRequired 属性设置点击次数，单击设置为 1，双击设置为 2
（3）如果一个控件既监听了单击事件也监听了双击事件，默认当双击事件触发的时候也同时会触发单击事件。如果想双击时不触发单击，需要通过 require(toFail:) 进行设置
// UITapGestureRecognizer：轻点手势（点击）functapGestureRecognizer(){//单击监听lettapSingle=UITapGestureRecognizer(target:self,action:#selector(tapSingleDid))tapSingle.numberOfTapsRequired=1tapSingle.numberOfTouchesRequired=1//双击监听lettapDouble=UITapGestureRecognizer(target:self,action:#selector(tapDoubleDid(_:)))tapDouble.numberOfTapsRequired=2tapDouble.numberOfTouchesRequired=1//声明点击事件需要双击事件检测失败后才会执行tapSingle.require(toFail:tapDouble)self.view.addGestureRecognizer(tapSingle)self.view.addGestureRecognizer(tapDouble)}@objcfunctapSingleDid(){print("单击了")}@objcfunctapDoubleDid(_sender:UITapGestureRecognizer){ifsender.view==self.view{print("双击了")}}``#####4、UIPinchGestureRecognizer：捏合手势（两个手指进行放大缩小）
// 捏合手势（两个手指进行放大缩小）
func pinchGestureRecognizer()
{
//设置监听方法为pinchDid方法
let pinch = UIPinchGestureRecognizer(target:self,action:#selector(pinchDid(_:)))
self.view.addGestureRecognizer(pinch)
}
@objc func pinchDid(_ recognizer:UIPinchGestureRecognizer) {
//在监听方法中可以实时获得捏合的比例
print(recognizer.scale)
//获取两个触摸点的坐标
print(recognizer.location(ofTouch: 0, in: self.view))
print(recognizer.location(ofTouch: 1, in: self.view))
}
``
注：recognizer.location使用这个的时候需要判断ofTouch: 1是否存在，因为当你手指捏合松开一个手指的瞬间这个是空的，会造成崩溃。
5、UIRotationGestureRecognizer：旋转手势（两个手指进行旋转）
// 旋转手势（两个手指进行旋转）funcrotationGestureRecognizer(){letrotation=UIRotationGestureRecognizer(target:self,action:#selector(rotationDid(_:)))self.view.addGestureRecognizer(rotation)}@objcfuncrotationDid(_recognizer:UIRotationGestureRecognizer){//旋转的弧度转换为角度print(recognizer.rotation*(180/CGFloat.pi))}
6、UIPanGestureRecognizer：拖动手势
// 拖动手势funcpanGestureRecognizer(){rect=UIView(frame:CGRect(x:0,y:0,width:100,height:100))rect.center=self.view.center rect.backgroundColor=UIColor.orangeself.view.addSubview(rect)letpan=UIPanGestureRecognizer(target:self,action:#selector(panDid(_:)))pan.maximumNumberOfTouches=1rect.addGestureRecognizer(pan)}@objcfuncpanDid(_recognizer:UISwipeGestureRecognizer){letpoint=recognizer.location(in:self.view)//设置矩形的位置rect.center=point}
通过 recognizer.view 我们可以直接得到触发事件的 view 对象，下面样例创建两个方块，但它们使用同一个拖动响应方法。（注意：由于一个 GestureRecognizer 只能对应一个 view，所以每个 view 还是要分别使用各自的 GestureRecognizer）
// 拖动手势funcpanGestureRecognizer2(){//定义两个方块letrect1=UIView(frame:CGRect(x:0,y:0,width:100,height:100))rect1.center=self.view.center rect1.backgroundColor=UIColor.orangeself.view.addSubview(rect1)letrect2=UIView(frame:CGRect(x:0,y:0,width:100,height:100))//rect2.center = self.view.centerrect2.backgroundColor=UIColor.yellowself.view.addSubview(rect2)//由于一个GestureRecognizer只能对应一个view，这里定义两个GestureRecognizerletpan1=UIPanGestureRecognizer(target:self,action:#selector(panDid2(_:)))pan1.maximumNumberOfTouches=1rect1.addGestureRecognizer(pan1)letpan2=UIPanGestureRecognizer(target:self,action:#selector(panDid2(_:)))pan2.maximumNumberOfTouches=1rect2.addGestureRecognizer(pan2)}//两个方块都使用同一拖拽响应方法@objcfuncpanDid2(_recognizer:UIPanGestureRecognizer){letpoint=recognizer.location(in:self.view)//设置矩形的位置recognizer.view?.center=point}
7、UILongPressGestureRecognizer：长按
/// 长按funclongPressGestureRecognizer(){//长按监听letlongPress=UILongPressGestureRecognizer(target:self,action:#selector(longPressDid(_:)))self.view.addGestureRecognizer(longPress)}@objcfunclongPressDid(_sender:UILongPressGestureRecognizer){ifsender.state==.began{print("长按响应开始")}else{print("长按响应结束")}}
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