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 == 2
        {
            //获取触摸集合
            let twoTouches = (touches as NSSet).allObjects
            
            //获取触摸数组
            let first:UITouch = twoTouches[0] as! UITouch //第1个触摸点
            let second:UITouch = twoTouches[1]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 = 1 //单击次数
        atap.numberOfTouchesRequired = 1 //手指个数
        
        //拖动事件
        let aPan = UIPanGestureRecognizer(target: self, action: "handlenPan:")
        self.view.addGestureRecognizer(aPan)
        aPan.minimumNumberOfTouches = 1 //最少手指个数
        aPan.maximumNumberOfTouches = 3 //最多手指个数
        
        //长按事件
        let aLongPress = UILongPressGestureRecognizer(target: self, action: "longPress:")
        self.view.addGestureRecognizer(aLongPress)
        aLongPress.minimumPressDuration = 1 //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")
    }