UITapGestureRecognizer is not called in sub views? - ios

Question

My scenario is that there will be many sub views in the main view and tapping on each sub view should generate different result.
My approach is for each sub view to implement its own tap recognizer, instead of for the main view to have one single tap recognizer and calculate the which sub view's area the user has tapped in. Is this a correct and viable approach?
I have tried this approach but it doesn't seem to work. The tap method never gets called. I read lots of articles on stackoverflow but they didn't seem to help.
For example, although the sub view is not an image view I still manually set its userInteractionEnabled property to YES, as some posts suggested. But that didn't help.
Below is the main code of the sub view:
- (void) handleOneTap:(UITapGestureRecognizer*)paramSender{
// *** Never gets called
NSUInteger touchCounter = 0; for (touchCounter = 0;
touchCounter < paramSender.numberOfTouchesRequired;
touchCounter++){
CGPoint touchPoint = [paramSender locationOfTouch:touchCounter
inView:paramSender.view];
NSLog(#"Touch #%lu: %#",
(unsigned long)touchCounter+1, NSStringFromCGPoint(touchPoint));
}
}
- (void)viewDidLoad {
[super viewDidLoad];
_container = [[UIView alloc] initWithFrame:CGRectMake(20, 50, 280, 300)];
[self.view addSubview:_container];
_container.backgroundColor = [UIColor redColor];
_container.opaque = YES;
// setup tap recognizer
self.tapGestureRecognizer = [[UITapGestureRecognizer alloc]
initWithTarget:self
action:#selector(handleOneTap:)];
self.tapGestureRecognizer.numberOfTouchesRequired = 1;
self.tapGestureRecognizer.numberOfTapsRequired = 1;
self.view.userInteractionEnabled = YES;
self.container.userInteractionEnabled = YES;
[self.view addGestureRecognizer:self.tapGestureRecognizer];
}
Any help will be appreciated.

Answer 1

If you want to add UIGestureRecognizer to your subview, you should do it like that:
_container = [[UIView alloc] initWithFrame:CGRectMake(20, 50, 280, 300)];
[self.view addSubview:_container];
_container.backgroundColor = [UIColor redColor];
_container.opaque = YES;
_container.userInteractionEnabled = YES;
self.tapGestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(handleOneTap:)];
self.tapGestureRecognizer.numberOfTouchesRequired = 1;
self.tapGestureRecognizer.numberOfTapsRequired = 1;
self.view.userInteractionEnabled = YES;
[_container addGestureRecognizer:self.tapGestureRecognizer];

Answer 2

It looks like that problem is not in UITapGestureRecognizer, but in case how you add Subview from ViewController.
Right way to add subviewcontoller is:
SSubViewController *pvc = [SSubViewController controllerWithSubViewID:0];
[self.view addSubview:pvc.view];
[self addChildViewController:pvc];
Do it in your ViewController and it should solve your problem