iOS UIPickerView: How to limit the scrolling range

Question

When you scroll UIPickerView you can move your finger on the touchpad up and down - far up and down to how big the screen is. Is there a way to limit this range of scrolling up and down to the area of the UIPickerView ? So that once you move your finger outside of the UIPickerView the scrolling of the UIPickerView stops? I am making UIPIckerView as a spinner in a game, and I need to achieve this for a fair gaming.

Answer 1

you can use UITapGestureRecognizer with UIPickerView and then you can get coordinate. If you get point in your desired frame then do your work otherwise return

Answer 2

//viewDidLoad

UILongPressGestureRecognizer* gestureRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(pickerLongPressDetected:)];
    gestureRecognizer.minimumPressDuration = .001;
    gestureRecognizer.cancelsTouchesInView = NO;
    gestureRecognizer.delegate = self;
    [self.rollerView addGestureRecognizer:gestureRecognizer];

-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
    // return
    return true;
}

-(void)pickerLongPressDetected:(UILongPressGestureRecognizer *)gesture
{
    CGPoint touchPoint = [gesture locationInView:self.view];

    CGRect frame = self.rollerView.frame;

    if(!CGRectContainsPoint(frame, touchPoint))
    {
        //methods for when you scroll outside of your picker view's frame
    }
}