触摸与手势学习-swift

触摸是一个UITouch对象，该对象放在一个UIEvent中，每个UIEvent包含一个或多个UITouch对象，每个UITouch对象对应一个手指。系统将UIEvent发送到应用程序上，最后应用程序将UIEvent传递给当前的一个UIView。

触摸分为5个阶段：

1）Began

2）Moved

3)Stationary

4)Ended

5)Cancelled（比如收到电话）

//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")
    }

手势UIGestureRecognizer：

UITapGestureRecognizer

UIPanGestureRecognizer

UILongPressGestureRecognizer

UIPinchGestureRecognizer

UISwipeGestureRecognizer

        //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")
     }