shouldReceiveTouch not called - ios

Question

I see a lot of question about it on web, and particularly on StackOverflow.
I test many given answers but in my case, nothing works.
My class implements the protocol UIGestureRecognizerDelegate:
#interface CDMapViewController : CDViewController <UIGestureRecognizerDelegate>
The following method is wrote from xcode autocompletion in #implentation of my class
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer
shouldReceiveTouch:(UITouch *)touch {
NSLog(#"not called");
return NO;
}
I have correctly init the UIGestureRecognizer in first method which correctly call the second, third and fourth methods:
- (void)initGestureOnMap {
UIGestureRecognizer *gestureRecognizer = [[UIGestureRecognizer alloc] init];
gestureRecognizer.delegate = self;
[self.view addGestureRecognizer:gestureRecognizer];
}
- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
gesture_dragging = NO;
}
- (void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesMoved:touches withEvent:event];
gesture_dragging = YES;
}
- (void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesEnded:touches withEvent:event];
if (gesture_dragging || [touches count] != 1) return;
/* bla bla bla */
}
... It doesn't log – not called ... why ?

Answer 1

You need to call super implementations for the touches methods.
- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
gesture_dragging = NO;
}
... and so on.
These methods need to be implemented on your view, and not your view controller.
Pick what kind of gesture you want. By itself, UIGestureRecognizer doesn't do much, so pick one like UITapGestureRecognizer. Next, implement your gesture recognizer with the designated initializer.
UITapGestureRecognizer *gestureRecognizer = [[UITapGestureRecognizer alloc] initWithTarget:self action:#selector(myMethod:)];
Finally, implement myMethod:.
-(void)myMethod:(UITapGestureRecognizer *)recognizer
{
// Whatever this does.
}