Protocol

UICollectionViewDragDelegate

The interface for initiating drags from a collection view.

Declaration

@protocol UICollectionViewDragDelegate

Overview

Implement this protocol in the object that you use to initiate drags from your collection view. The only required method of this protocol is the collectionView:itemsForBeginningDragSession:atIndexPath: method, but you can implement other methods as needed to customize the drag behavior of your collection view.

Assign your custom delegate object to the dragDelegate property of your collection view.

Topics

Providing the Items to Drag

- collectionView:itemsForBeginningDragSession:atIndexPath:

Provides the initial set of items (if any) to drag.

Required.

- collectionView:itemsForAddingToDragSession:atIndexPath:point:

Adds the specified items to an existing drag session.

Tracking the Drag Session

- collectionView:dragSessionWillBegin:

Called to let you know that a drag session is about to begin for the collection view.

Providing a Custom Preview

- collectionView:dragPreviewParametersForItemAtIndexPath:

Returns custom information about how to display the item at the specified location during the drag.

Relationships

Inherits From

See Also

Drag and Drop

Supporting Drag and Drop in Collection Views

Initiate drags and handle drops from a collection view.

UICollectionViewDropDelegate

The interface for handling drops in a collection view.

UICollectionViewDropCoordinator

An interface for coordinating your custom drop-related actions with the collection view.

UICollectionViewDropProposal

Your proposed solution for handling a drop in a collection view.

UICollectionViewDropItem

The data associated with an item being dropped into the collection view.

UICollectionViewDropPlaceholderContext

An object that contains information about a placeholder in the collection view.

UIDataSourceTranslating

An advanced interface for managing a data source object.

Beta Software

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