When did `UICollectionView` come to an end

Question

Im using a UICollectionView and using a UIButton to scroll from cell to cell. I want the button.hidden = YES when I come to the end of the collection view. How do I know when currentIndex == MAX

Answer 1

A collection view is a scroll view. You therefore have access to all of the scroll view delegate methods - scrollViewDidScroll: will be called every time the scroll view moves, you can check at that point if you've scrolled to the bottom, or end, or wherever.

Note that the contentOffset property will refer to the origin of the visible scroll area, so it's probably simplest to check something like this:

if (CGRectGetMaxY(scrollView.bounds) == scrollView.contentSize.height) {
    button.hidden = YES;
}

This delegate method would not be called if you scrolled the view yourself, however - it would only apply if the view was scrolled by the user. You'd need to either call this yourself at the end of your automatic scrolling code or have similar logic in your automatic scrolling code to check this yourself.