Limit area of screen to UIPanGestureRecognizer [duplicate] - ios

Question

This question already has answers here:
exclude subview from UITapGestureRecognizer
(3 answers)
Closed 9 years ago.
This is how I add gesture on view
- (void)_addPanGestureToView:(UIView *)view {
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(_handlePan:)];
panGesture.delegate = self;
panGesture.maximumNumberOfTouches = 1;
panGesture.minimumNumberOfTouches = 1;
[view addGestureRecognizer:panGesture];
}
Everything is working perfectly, but gesture is on the whole view how could I do something like gesture respond only in half of view?

Answer 1

Why not just use CGRectContainsPoint() and check if the touches location within your view is within the area you want it to be. If it isn't, ignore it:
- (void)panGestureDetected:(UIPanGestureRecognizer *)sender
{
CGPoint location = [sender locationInView:sender.view];
CGRect someRect = ...
if (CGRectContainsPoint(someRect, location)) {
// point is in specified area
}
}

Answer 2

Easiest solution would be adding a transparent view on the area where you want you gesture recognizer to work, and add the gesture to that view (and that view as a subview of course).
Somthing like:
- (void)_addPanGestureToView:(UIView *)view {
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:#selector(_handlePan:)];
panGesture.delegate = self;
panGesture.maximumNumberOfTouches = 1;
panGesture.minimumNumberOfTouches = 1;
UIView *viewForGesture = [[UIView alloc] initWithFrame:CGRectMake(....)]; //your frame
[viewForGesture addGestureRecognizer:panGesture];
[view addSubview:viewForGesture];
}