Instance Method

collectionView:dropSessionDidUpdate:withDestinationIndexPath:

Tells your delegate that the position of the dragged data over the collection view changed.

Declaration

- (UICollectionViewDropProposal *)collectionView:(UICollectionView *)collectionView dropSessionDidUpdate:(id<UIDropSession>)session withDestinationIndexPath:(NSIndexPath *)destinationIndexPath;

Parameters

collectionView

The collection view that is tracking the dragged content.

session

The drop session object containing information about the type of data being dragged.

destinationIndexPath

The index path at which the content would be dropped.

Return Value

Your proposal for how to handle the content if it is dropped at the specified location.

Discussion

While the user is dragging content, the collection view calls this method repeatedly to determine how you would handle the drop if it occurred at the specified location. The collection view provides visual feedback to the user based on your proposal.

In your implementation of this method, create a UICollectionViewDropProposal object and use it to convey your intentions. Because this method is called repeatedly while the user drags over the table view, your implementation should return as quickly as possible.

See Also

Tracking the Drag Movements

- collectionView:dropSessionDidEnter:

Called when dragged content enters the collection view's bounds rectangle.

- collectionView:dropSessionDidExit:

Called when dragged content exits the table view's bounds rectangle.

- collectionView:dropSessionDidEnd:

Called to notify you when the drag operation ends.