Question

My program basically looks like this:

UIViewController -> Custom UIView -> [Array of UIImageView]

My problem is that my recognizer’s action method is never called. I’ve already set the userInteractionEnabled attribute of my UIImageViews to YES.

On my View Controller’s viewDidLoad:

- (void)viewDidLoad
{
    NSEnumerator *enumerator = [grid.subviews objectEnumerator];
    UIImageView *view;
    UITapGestureRecognizer *recognizer;

    while((view = [enumerator nextObject])){
        recognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(openDeal:)];

        view.userInteractionEnabled = YES;
        recognizer.delegate = self;
        recognizer.numberOfTapsRequired = 1;
        [view addGestureRecognizer:recognizer];
        NSLog(@"%d", (int)view.userInteractionEnabled);
        [recognizer release];
    }
    [super viewDidLoad];
}

and openDeal is defined as such:

-(void) openDeal:(UITapGestureRecognizer *) recognizer{
    NSLog(@"%@",[NSString stringWithFormat:@"%d", recognizer.view.tag]);
}

Answer 1

I had the same issue and later found out that I was assigning the same gesture recognizer instance to another view. Gesture recognizers can be associated to a single view only (you can verify that through UIGestureRecognizer’s view property).

Make sure you are not reusing your recognizers somewhere else in the code.