UIKit中包含了UIGestureRecognizer类，用于检测发生在设备中的手势。UIGestureRecognizer是一个抽象类，定义了所有手势的基本行为，它有下面一些子类用于处理具体的手势： 

    1、拍击UITapGestureRecognizer (任意次数的拍击)      2、向里或向外捏UIPinchGestureRecognizer (用于缩放)      3、摇动或者拖拽UIPanGestureRecognizer      4、滑动UISwipeGestureRecognizer (以任意方向)      5、旋转UIRotationGestureRecognizer (手指朝相反方向移动)      6、长按UILongPressGestureRecognizer 对于不同类型的手势识别器，具有不同的配置属性。比如UITapGestureRecognizer，可以配置拍击次数。界面接收到手势之后，可以发送一 个消息，用于处理响应手势动作后的任务。当然，不同的手势识别器，发送的消息方法也会有所不同。下面列举几个具体示例代码：

 

一个手指，拍击两次手势

    

    // 创建一个手势识别器

    UITapGestureRecognizer *oneFingerTwoTaps =

    [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(oneFingerTwoTaps)] autorelease];

    // Set required taps and number of touches

    [oneFingerTwoTaps setNumberOfTapsRequired:2];

    [oneFingerTwoTaps setNumberOfTouchesRequired:1];

    // Add the gesture to the vie

    [[self view] addGestureRecognizer:oneFingerTwoTaps];

    //消息方法oneFingerTwoTaps

    - (void)oneFingerTwoTaps

    {

        NSLog(@"Action: One finger, two taps");

    }

两个手指，拍击两次手势

    UITapGestureRecognizer *twoFingersTwoTaps =

    [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(twoFingersTwoTaps)] autorelease];

    [twoFingersTwoTaps setNumberOfTapsRequired:2];

    [twoFingersTwoTaps setNumberOfTouchesRequired:2];

    [[self view] addGestureRecognizer:twoFingersTwoTaps];

    

    //消息方法twoFingersTwoTaps

    - (void)twoFingersTwoTaps {

        NSLog(@"Action: Two fingers, two taps");

    } 

 

一个手指向上、向下滑动手势

// 向上滑动

UISwipeGestureRecognizer *oneFingerSwipeUp =

[[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(oneFingerSwipeUp:)] autorelease];

[oneFingerSwipeUp setDirection:UISwipeGestureRecognizerDirectionUp];

[[self view] addGestureRecognizer:oneFingerSwipeUp];

- (void)oneFingerSwipeUp:(UISwipeGestureRecognizer *)recognizer

{

    CGPoint point = [recognizer locationInView:[self view]];

    NSLog(@"Swipe up - start location: %f,%f", point.x, point.y);

}

// 向下滑动

UISwipeGestureRecognizer *oneFingerSwipeDown =

[[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(oneFingerSwipeDown:)] autorelease];

[oneFingerSwipeDown setDirection:UISwipeGestureRecognizerDirectionDown];

[[self view] addGestureRecognizer:oneFingerSwipeDown];

- (void)oneFingerSwipeDown:(UISwipeGestureRecognizer *)recognizer

{

    CGPoint point = [recognizer locationInView:[self view]];

    NSLog(@"Swipe down - start location: %f,%f", point.x, point.y);

}

 

旋转手势

UIRotationGestureRecognizer *twoFingersRotate =

[[[UIRotationGestureRecognizer alloc] initWithTarget:self action:@selector(twoFingersRotate:)] autorelease];

[[self view] addGestureRecognizer:twoFingersRotate];

- (void)twoFingersRotate:(UIRotationGestureRecognizer *)recognizer

{

    // Convert the radian value to show the degree of rotation

    NSLog(@"Rotation in degrees since last change: %f", [recognizer rotation] * (180 / M_PI));

}

 

向里或向外捏的手势

UIPinchGestureRecognizer *twoFingerPinch =[[[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(twoFingerPinch:)] autorelease];[[self view] addGestureRecognizer:twoFingerPinch];- (void)twoFingerPinch:(UIPinchGestureRecognizer *)recognizer{    NSLog(@"Pinch scale: %f", recognizer.scale);}

    UITapGestureRecognizer *twoFingersTwoTaps =

    [[[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(twoFingersTwoTaps)] autorelease];

    [twoFingersTwoTaps setNumberOfTapsRequired:2];

    [twoFingersTwoTaps setNumberOfTouchesRequired:2];

    [[self view] addGestureRecognizer:twoFingersTwoTaps];

//消息方法twoFingersTwoTaps- (void)twoFingersTwoTaps {    NSLog(@"Action: Two fingers, two taps");}