Check whether cell at indexPath is visible on screen UICollectionView

Question

I have a CollectionView which displays images to the user. I download these in the background, and when the download is complete I call the following func to update

Answer 1

You can simply use if collectionView.cellForItem(at: indexPath) == nil { }. The collectionView will only return a cell if it is visible.

Or in your case specifically change:

let cell = followedCollectionView.cellForItemAtIndexPath(indexPath) as! FeaturedCitiesCollectionViewCell

to:

if let cell = followedCollectionView.cellForItemAtIndexPath(indexPath) as? FeaturedCitiesCollectionViewCell { }