iphone－响应上下左右滑动手势

-(void)viewDidLoad{

UISwipeGestureRecognizer *recognizer; 

recognizer = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(handleSwipeFrom:)];

     [recognizer setDirection:(UISwipeGestureRecognizerDirectionRight)];
    [[self view] addGestureRecognizer:recognizer];
[recognizer release];
    recognizer = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(handleSwipeFrom:)];

     [recognizer setDirection:(UISwipeGestureRecognizerDirectionLeft)];
    [[self view] addGestureRecognizer:recognizer];
[recognizer release];
 
recognizer = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(handleSwipeFrom:)];

     [recognizer setDirection:(UISwipeGestureRecognizerDirectionUp)];
    [[self view] addGestureRecognizer:recognizer];
[recognizer release];
 

 
UISwipeGestureRecognizer *recognizer;

    recognizer = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(handleSwipeFrom:)];
     [recognizer setDirection:(UISwipeGestureRecognizerDirectionDown)];
    [[self view] addGestureRecognizer:recognizer];
[recognizer release];


}

-(void)handleSwipeFrom:(UISwipeGestureRecognizer *)recognizer{

if(recognizer.direction==UISwipeGestureRecognizerDirectionDown) {

       NSLog(@"swipe down");
//执行程序
}
if(recognizer.direction==UISwipeGestureRecognizerDirectionUp) {

       NSLog(@"swipe up");
//执行程序
}

if(recognizer.direction==UISwipeGestureRecognizerDirectionLeft) {

       NSLog(@"swipe left");
//执行程序
}

if(recognizer.direction==UISwipeGestureRecognizerDirectionRight) {

       NSLog(@"swipe right");
//执行程序
}

}