8.1 Detecting Swipe Gestures

滑动手势

#import "ViewController.h"

@interface ViewController ()

@property (nonatomic, retain)UISwipeGestureRecognizer *swipeGestureRecognizer;

@end

@implementation ViewController

- (void) handleSwipes:(UISwipeGestureRecognizer *)paramSender{

    NSLog(@"paramSender.direction= %d",paramSender.direction);

    if (paramSender.direction & UISwipeGestureRecognizerDirectionDown){

        NSLog(@"Swiped Down.");

    }

    if (paramSender.direction & UISwipeGestureRecognizerDirectionLeft){

        NSLog(@"Swiped Left.");

    }

    if (paramSender.direction & UISwipeGestureRecognizerDirectionRight){

        NSLog(@"Swiped Right.");

    }

    if (paramSender.direction & UISwipeGestureRecognizerDirectionUp){

        NSLog(@"Swiped Up.");

    }

}

- (void)viewDidLoad

{

    [super viewDidLoad];

    /* Instantiate the object */

    self.swipeGestureRecognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self

                                                                            action:@selector(handleSwipes:)];

    /* Swipes that are performed from right to left are to be detected */

    self.swipeGestureRecognizer.direction = UISwipeGestureRecognizerDirectionLeft| UISwipeGestureRecognizerDirectionDown | UISwipeGestureRecognizerDirectionRight | UISwipeGestureRecognizerDirectionUp;

    /* Just one finger needed */

    self.swipeGestureRecognizer.numberOfTouchesRequired = 1;

    /* Add it to the view */

    [self.view addGestureRecognizer:self.swipeGestureRecognizer];

}

- (void)didReceiveMemoryWarning

{

    [super didReceiveMemoryWarning];

    // Dispose of any resources that can be recreated.

}

@end

输出：

2014-04-09 15:37:05.210 cookbook[686:a0b] paramSender.direction= 15

2014-04-09 15:37:05.211 cookbook[686:a0b] Swiped Down.

2014-04-09 15:37:05.211 cookbook[686:a0b] Swiped Left.

2014-04-09 15:37:05.212 cookbook[686:a0b] Swiped Right.

2014-04-09 15:37:05.212 cookbook[686:a0b] Swiped Up.

发现只有左右滑有响应，上下滑没响应，不知道是不是我理解有误还是怎么着。懂的人请留言