（轉）iOS手勢UIGestureRecognizer

UIKit中包含了UIGestureRecognizer類，用於檢測發生在設備中的手勢。UIGestureRecognizer是一個抽象類，定義了全部手勢的基本行爲，它有下面一些子類用於處理具體的手勢： 

    一、拍擊UITapGestureRecognizer (任意次數的拍擊)  
    二、向裏或向外捏UIPinchGestureRecognizer (用於縮放)  
    三、搖動或者拖拽UIPanGestureRecognizer  
    四、擦碰UISwipeGestureRecognizer (以任意方向)  
    五、旋轉UIRotationGestureRecognizer (手指朝相反方向移動)  
    六、長按UILongPressGestureRecognizer 

對於不一樣類型的手勢識別器，具備不一樣的配置屬性。好比UITapGestureRecognizer，能夠配置拍擊次數。界面接收到手勢以後，能夠發送一個消息，用於處理響應手勢動做後的任務。固然，不一樣的手勢識別器，發送的消息方法也會有所不一樣。

[代碼] 一個手指，拍擊兩次手勢

// 建立一個手勢識別器 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"); }

[代碼] 兩個手指，拍擊兩次手勢

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"); } 

[代碼] 一個手指向上、向下擦碰手勢

// 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); }

[代碼] 旋轉手勢

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)); }

[代碼] 向裏或向外捏的手勢

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