使用iOS手势UIGestureRecognizer

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、擦碰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 view

[[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、向下擦碰手势

// 向上擦碰

    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);

    }

    // 向下擦碰

    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);

}

来源：oschina

链接：https://my.oschina.net/u/254222/blog/60972

标签

ios

手势