Pass UICollectionView touch event to its parent UI

Question

Here is the view structure:

The outer view is a UITableView.

Inside the UITableViewCell, there is a UICollectionView. And notice that there is some black spacing between the collection view cells.

When I tap the spacing in the UICollectionView, I want the touch event to pass to the UITableViewCell.

Answer 1

After google around, I have found a solution.Just inherit UICollectionView class and override hitTest:withEvent method.

CustomCollectionView.h

@interface CustomCollectionView : UICollectionView

@end

CustomCollectionView.m

@implementation CustomCollectionView

- (UIView *)hitTest:(CGPoint)point withEvent:(UIEvent *)event {

    UIView *hitView = [super hitTest:point withEvent:event];

    if ([hitView isKindOfClass:[self class]]) {
        // If it is class UICollectionView,just return nil.
        return nil;
    }
    // else return super implementation.
    return [super hitTest:point withEvent:event];
}

@end

Answer 2

Is that possible to set collectionView's backgroundView UserInteraction not enable, but make sure the collectionViewCell did, so that it could pass the tapEvent to next responder.

- (void)viewDidLoad {
    theCollectionView.userInteractionEnabled = NO;
}

I hope it would help.

Answer 3

Code from highest voted answer can be easily shortened.

Swift 4.1:

final class InteractiveCollectionView: UICollectionView {
    override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
        return super.hitTest(point, with: event) as? InteractiveCollectionView
    }
}

Answer 4

Excellent answer by @tounaobun. Tested and it works as expected:

1) If you tap anywhere on the collection view that is not an item, then the table cell underneath will select just fine.

2) if you tap on the items in the collection view, then the table cell will not select and you can interact with the collection view normally (aka, scrolling, invoking didSelectItem, etc)

I converted to swift for reference:

Swift 3:

class TableCellCollectionView: UICollectionView { 

 override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
    if let hitView = super.hitTest(point, with: event) {
        if hitView is TableCellCollectionView {
            return nil
        } else {
            return hitView
        }
    } else {
        return nil
    }

}

Just add this class definition to your code (I have it in a utility file) and then change the collection view's class from UICollectionView to TableCellCollectionView and you should be all set.