I ran into this very same problem when inserting the first cell into a collection view. I fixed the problem by changing my code so that I call the UICollectionView
- (void)reloadData
method when inserting the first cell, but
- (void)insertItemsAtIndexPaths:(NSArray *)indexPaths
when inserting all other cells.
Interestingly, I also had a problem with
- (void)deleteItemsAtIndexPaths:(NSArray *)indexPaths
when deleting the last cell. I did the same thing as before: just call reloadData when deleting the last cell.