How to change UICollectionView zIndex?

Question

Check the image below. I need to highlight the focused cell such that it is above all the cells in collectionView.
I know I have to change the zIndex of the focused cell. How to do that?
I need the logic. My code is in objective-c.

This is for tvOS but iOS code will also work here I guess.

Answer 1

Have you tried setting value for cell.layer.zPosition?