Touch event handled by multiple views

Question

I have a subclass of UIView on top of a UITableView. I am using the UITableView to display some data and, at the same time, I would like to overlay an animation that follows the finger (for instance, leaving a trail).

If I get it right, I need the touch events to be handled both by the UIView subclass and the UITableView. How can I do that? Is it possible to have, ie, touchesMoved being triggered on the UIView subclass and then on UITableView?

Thank you so much for any help.

Answer 1

The way I have solved this problem is in a way that is not that clean, but it works. Please let me know if there's a better way to do this.

I have overridden hitTest for my custom UIView so that it directs touches to the UITableView underneath. Then in the UITableView I am handling the gestures through touchesBegan, touchesMoved, etc. There I am also calling touchesBegan on the UIView.

In this way touches are handled by two views. The reason why I am not doing the other way around (having UIView's touchesBegan calling UITableView's touchesBegan) is that gestures recognizers on the UITableView would not work.

UIView subclass' hitTest

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event
{
    // tview is the UITableView subclass instance
    CGPoint tViewHit = [tView convertPoint:point fromView:self];        
    if ([tView pointInside:tViewHit withEvent:event]) return tView;

    return [super hitTest:point withEvent:event];
}

UITableView subclass's touchesBegan

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [touches anyObject];
    CGPoint location = [touch locationInView:touch.view];
    // ....

    // view is the UIView's subclass instance
    [view touchesBegan:touches withEvent:event];
}