Invoked when the mouse is released over a collection view that previously allowed a drop.
Original signature is '- (BOOL)collectionView:(NSCollectionView *)collectionView acceptDrop:(id < NSDraggingInfo >)draggingInfo index:(NSInteger)index dropOperation:(NSCollectionViewDropOperation)dropOperation'
Available in Mac OS X v10.6 and later.

C# | Visual Basic | Visual C++ |
public delegate bool CollectionViewAcceptDropIndexDropOperationEventHandler( NSCollectionView collectionView, INSDraggingInfo draggingInfo, NSInteger index, NSCollectionViewDropOperation dropOperation )
Public Delegate Function CollectionViewAcceptDropIndexDropOperationEventHandler ( _ collectionView As NSCollectionView, _ draggingInfo As INSDraggingInfo, _ index As NSInteger, _ dropOperation As NSCollectionViewDropOperation _ ) As Boolean
public delegate bool CollectionViewAcceptDropIndexDropOperationEventHandler( NSCollectionView^ collectionView, INSDraggingInfo^ draggingInfo, NSInteger index, NSCollectionViewDropOperation dropOperation )

- collectionView (NSCollectionView)
- The collection view that send the message.
- draggingInfo (INSDraggingInfo)
- An object that contains more information about this dragging operation.
- index (NSInteger)
- The index of the proposed drop item.
- dropOperation (NSCollectionViewDropOperation)
- The type of dragging operation.

YES if the drop operation should be accepted, otherwise NO.

- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later)