# collectionView(_:writeItemsAt:to:) Places the data for the drag operation on the pasteboard. ``` optional func collectionView(_ collectionView: NSCollectionView, writeItemsAt indexPaths: Set, to pasteboard: NSPasteboard) -> Bool ``` ## Parameters `collectionView` The collection view making the request. `indexPaths` The index paths of the items being dragged. `pasteboard` The pasteboard on which to place the drag data. ## Return Value if the drag operation can continue or if you want to refuse the drag. ## Discussion You must implement this method or the [`collectionView(_:pasteboardWriterForItemAt:)`](/documentation/AppKit/NSCollectionViewDelegate/collectionView(_:pasteboardWriterForItemAt:)-5eyyl) method to support drag operations. The collection view calls the [`collectionView(_:pasteboardWriterForItemAt:)`](/documentation/AppKit/NSCollectionViewDelegate/collectionView(_:pasteboardWriterForItemAt:)-5eyyl) method in preference to this one if both are implemented. If your app supports multi-image drag and drop, you must implement the [`collectionView(_:pasteboardWriterForItemAt:)`](/documentation/AppKit/NSCollectionViewDelegate/collectionView(_:pasteboardWriterForItemAt:)-5eyyl) method. The collection view calls this method after it has determined that a drag should begin but before the drag operation has started. Your implementation of this method should do the following: 1. Declare the pasteboard types you support using the [`declareTypes(_:owner:)`](/documentation/AppKit/NSPasteboard/declareTypes(_:owner:)) method of the provided `pasteboard` object. 2. Write data to the pasteboard for each type you declare. 3. Return from this method. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)