iphone - 为什么我的 UIGestureRecognizer 代码不起作用？

Question

为什么下面的代码不起作用？

- (void)viewDidLoad
{    

UISwipeGestureRecognizer *oneFingerSwipeLeft = 
[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(oneFingerSwipeLeft:)];
[oneFingerSwipeLeft setDirection:UISwipeGestureRecognizerDirectionLeft];
[[self view] addGestureRecognizer:oneFingerSwipeLeft];

UISwipeGestureRecognizer *oneFingerSwipeRight = 
[[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(oneFingerSwipeRight:)];
[oneFingerSwipeRight setDirection:UISwipeGestureRecognizerDirectionRight];
[[self view] addGestureRecognizer:oneFingerSwipeRight];

}

- (void)oneFingerSwipeLeft:(UISwipeGestureRecognizer *)recognizer 
{ 
CGPoint point = [recognizer locationInView:[self view]];
NSLog(@"Swipe up - start location: %f,%f", point.x, point.y);
}

- (void)oneFingerSwipeRight:(UISwipeGestureRecognizer *)recognizer 
{ 
CGPoint point = [recognizer locationInView:[self view]];
NSLog(@"Swipe down - start location: %f,%f", point.x, point.y);
}

请记住，我在裸 View 前面有很多层(例如图像、按钮和标签)。这会有所作为吗？如何在所有这些层之上识别手势？

谢谢!

Answer 1

仔细检查并确保您要添加 UIGestureRecognizer 的 UIView 已将 UserInteractionEnabled 设置为 YES。即

[self.imageView setUserInteractionEnabled:YES];