iOS 手势识别 - gestureRecognizer

iOS设备的手势操作，在app中是个必须且实用的功能，为app加分不少。

向左向右轻划

UISwipeGestureRecognizer *swipeLeft = [[UISwipeGestureRecognizer alloc] initWithTarget:self  action:@selector(handleSwipeLeft)];  
swipeLeft.direction = UISwipeGestureRecognizerDirectionLeft;  
[self.view addGestureRecognizer:swipeLeft];  
[swipeLeft release];  
UISwipeGestureRecognizer *swipeRight = [[UISwipeGestureRecognizer alloc]   
                                         initWithTarget:self   
                                                 action:@selector(handleSwipeRight)];  
swipeRight.direction = UISwipeGestureRecognizerDirectionRight;  
[self.view addGestureRecognizer:swipeRight];  
[swipeRight release];  

单指单击

UITapGestureRecognizer *singleFingerOne = [[UITapGestureRecognizer alloc] initWithTarget:self   
                  action:@selector(handleSingleFingerEvent:)];  
singleFingerOne.numberOfTouchesRequired = 1; //手指数  
singleFingerOne.numberOfTapsRequired = 1; //tap次数  
singleFingerOne.delegate = self;  
[self.view addGestureRecognizer:singleFingerOne];  

单指双击

UITapGestureRecognizer *singleFingerTwo = [[UITapGestureRecognizer alloc] initWithTarget:self   action:@selector(handleSingleFingerEvent:)];  
singleFingerTwo.numberOfTouchesRequired = 1;  
singleFingerTwo.numberOfTapsRequired = 2;  
singleFingerTwo.delegate = self;  
[self.view addGestureRecognizer:singleFingerTwo];  

双指单击和双击

 UITapGestureRecognizer *doubleFingerOne = [[UITapGestureRecognizer alloc] initWithTarget:self   
                            action:@selector(handleDoubleFingerEvent:)];  
 doubleFingerOne.numberOfTouchesRequired = 2;  
doubleFingerOne.numberOfTapsRequired = 1;  
doubleFingerOne.delegate = self;  
UITapGestureRecognizer *doubleFingerTwo = [[UITapGestureRecognizer alloc]  initWithTarget:self  action:@selector(handleDoubleFingerEvent:)];  
doubleFingerTwo.numberOfTouchesRequired = 2;  
doubleFingerTwo.numberOfTapsRequired = 2;  
doubleFingerTwo.delegate = self;  
[self.view addGestureRecognizer:doubleFingerOne];  
[self.view addGestureRecognizer:doubleFingerTwo];  

//如果不加下面的话，当单指双击时，会先调用单指单击中的处理，再调用单指双击中的处理  
[singleFingerOne requireGestureRecognizerToFail:singleFingerTwo];  
//同理双指亦是如此  
[doubleFingerOne requireGestureRecognizerToFail:doubleFingerTwo];  

事件处理方法：

 - (void)handleSingleFingerEvent:(UITapGestureRecognizer *)sender  
 {  
    if (sender.numberOfTapsRequired == 1) {  
        //单指单击  
        NSLog(@"单指单击");  
    }else if(sender.numberOfTapsRequired == 2){  
        //单指双击  
        NSLog(@"单指双击");  
     }  
 }  
 //处理双指事件  
 - (void)handleDoubleFingerEvent:(UITapGestureRecognizer *)sender  
 {  
    if (sender.numberOfTapsRequired == 1) {  
         //双指单击  
         NSLog(@"双指单击");  
     }else if(sender.numberOfTapsRequired == 2){  
         //双指双击  
         NSLog(@"双指双击");  
     }  
}