//触摸事件

    //手指首次触摸到屏幕

    override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {

        print("touchesBegan")

        //获取touches数量

        let numTouches = touches.count

        //获取点击屏幕的次数

        let tapTouches = (touches as NSSet).anyObject()?.tapCount

        //获取事件发生时间

        let timestamp = event!.timestamp

        //获取当前相对于self.view的坐标

        let locationPoint = (touches as NSSet).anyObject()?.locationInView(self.view)

        //获取上一次相对于self.view的坐标

        let previousPoint = (touches as NSSet).anyObject()?.previousLocationInView(self.view)

        //允许使用手势

        self.view.userInteractionEnabled = true

        //支持多点触摸

        self.view.multipleTouchEnabled = true

        print("\(tapTouches)")

        //判断如果有两个触摸点

        if touches.count ==

        {

            //获取触摸集合

            let twoTouches = (touches as NSSet).allObjects

            //获取触摸数组

            let first:UITouch = twoTouches[] as! UITouch //第1个触摸点

            let second:UITouch = twoTouches[]as! UITouch //第2个触摸点

            //获取第1个点相对于self.view的坐标

            let firstPoint:CGPoint = first.locationInView(self.view)

            //获取第1个点相对于self.view的坐标

            let secondPoint:CGPoint = second.locationInView(self.view)

            //计算两点之间的距离

            let deltaX = secondPoint.x - firstPoint.x;

            let deltaY = secondPoint.y - firstPoint.y;

            let initialDistance = sqrt(deltaX*deltaX + deltaY*deltaY )

            print("两点间距离是：\(initialDistance)")

        }

    }

    //手指在移动

    override func touchesMoved(touches: Set<UITouch>, withEvent event: UIEvent?) {

        print("touchesMoved")

    }

    //触摸结束

    override func touchesEnded(touches: Set<UITouch>, withEvent event: UIEvent?) {

        print("touchesEnded")

    }

    //触摸意外终止

    //模拟器演示：鼠标拖动的同时，按键盘command+shift+h 相当于点击手机home键，退出应用，触发touchesCancelled事件，在打电话、等情况下也会触发

    override func touchesCancelled(touches: Set<UITouch>?, withEvent event: UIEvent?) {

        print("touchesCancelled")

    }

        //点击事件

         let atap = UITapGestureRecognizer(target: self, action: "tapDo:")

         self.view.addGestureRecognizer(atap)

         atap.numberOfTapsRequired =  //单击次数

         atap.numberOfTouchesRequired =  //手指个数

         //拖动事件

         let aPan = UIPanGestureRecognizer(target: self, action: "handlenPan:")

         self.view.addGestureRecognizer(aPan)

         aPan.minimumNumberOfTouches =  //最少手指个数

         aPan.maximumNumberOfTouches =  //最多手指个数

         //长按事件

         let aLongPress = UILongPressGestureRecognizer(target: self, action: "longPress:")

         self.view.addGestureRecognizer(aLongPress)

         aLongPress.minimumPressDuration =  //需要长按的时间，最小0.5s

         //捏合事件

         let aPinch = UIPinchGestureRecognizer(target: self, action: "pinchDo:")

         self.view.addGestureRecognizer(aPinch)

         //旋转事件

         let aRotation = UIRotationGestureRecognizer(target: self, action: "rotatePiece:")

         self.view.addGestureRecognizer(aRotation)

         //轻扫事件--左轻扫

         let leftSwipe = UISwipeGestureRecognizer(target: self, action: "leftSwipe:")

         self.view.addGestureRecognizer(leftSwipe)

         leftSwipe.direction =  UISwipeGestureRecognizerDirection.Left

         //轻扫事件--右轻扫

         let rightSwipe = UISwipeGestureRecognizer(target: self, action: "rightSwipe:")

         self.view.addGestureRecognizer(rightSwipe)

         rightSwipe.direction =  UISwipeGestureRecognizerDirection.Right

         //轻扫事件--上轻扫

         let upSwipe = UISwipeGestureRecognizer(target: self, action: "upSwipe:")

         self.view.addGestureRecognizer(upSwipe)

         upSwipe.direction =  UISwipeGestureRecognizerDirection.Up

         //轻扫事件--下轻扫

         let downSwipe = UISwipeGestureRecognizer(target: self, action: "downSwipe:")

         self.view.addGestureRecognizer(downSwipe)

         downSwipe.direction =  UISwipeGestureRecognizerDirection.Down

 //手势

     //点击事件

     func tapDo(sender:UITapGestureRecognizer)

     {

         print("点击事件")

     }

     //拖动事件

     func handlenPan(sender:UIPanGestureRecognizer)

     {

         print("拖动事件")

         if sender.state == .Began

         {

             //拖动开始

         }

         else if sender.state == .Changed

         {

             //拖动过程

         }

         else if sender.state == .Ended

         {

             //拖动结束

         }

     }

     //长摁事件

     func longPress(sender:UILongPressGestureRecognizer)

     {

         print("长摁事件")

     }

     //捏合事件

     func pinchDo(sender:UIPinchGestureRecognizer)

     {

         print("捏合")

     }

     //旋转事件

     func rotatePiece(sender:UIRotationGestureRecognizer)

     {

         print("旋转")

     }

     //轻扫事件--左轻扫

     func leftSwipe(sender:UISwipeGestureRecognizer)

     {

         print("左轻扫")

     }

     //轻扫事件--右轻扫

     func rightSwipe(sender:UISwipeGestureRecognizer)

     {

         print("右轻扫")

     }

     //轻扫事件--上轻扫

     func upSwipe(sender:UISwipeGestureRecognizer)

     {

         print("上轻扫")

     }

     //轻扫事件--下轻扫

     func downSwipe(sender:UISwipeGestureRecognizer)

     {

         print("下轻扫")

     }