Weird animation in NSCollectionViewCompositionalLayout

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Created Apr ’23

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I'm implementing the drag and drop in a collection view, for the most part it works as expected but I have this weird bug that when I click on a item and start dragging it the item appears outside outside the view and it off from my mouse cursor. I have no idea what is causing this.

Screenshot 2023-04-19 at 4.17.35 PM.png

This is how I accept the drop and call the func moveItem from the collection view.

                        indexPath: IndexPath, dropOperation: NSCollectionView.DropOperation) -> Bool {
        guard !indexPathsOfItemsBeingDragged.isEmpty else { return false }
        var acceptDrop =  false
        for fromIndexPath in indexPathsOfItemsBeingDragged {
            var modelUpdated = false
            if fromIndexPath.section == indexPath.section { &#x2F;&#x2F;moving items in same section
                modelUpdated = dataSource.moveItemIn(section: fromIndexPath.section, fromIndex: fromIndexPath.item,
                                                     toIndex: indexPath.item)
            } else if fromIndexPath.section != indexPath.section{ &#x2F;&#x2F;move items between sections
                modelUpdated =  dataSource.moveItem(fromSection: fromIndexPath.section, fromIndex: fromIndexPath.item,
                                                    toSection: indexPath.section, toIndex: indexPath.item)
            }
            if modelUpdated { &#x2F;&#x2F;notify collection view if model was updated
                NSAnimationContext.current.duration = 0.25
                collectionView.animator().moveItem(at: fromIndexPath, to: indexPath)
                acceptDrop = true
            }
        }
        return acceptDrop
    }

This is how I set the constraints for my collection view.

`NSLayoutConstraint.activate([moviesCollectionView.leadingAnchor.constraint(equalTo: safeAreaLayoutGuide.leadingAnchor),
                                     moviesCollectionView.topAnchor.constraint(equalTo: safeAreaLayoutGuide.topAnchor),
                                     moviesCollectionView.trailingAnchor.constraint(equalTo: safeAreaLayoutGuide.trailingAnchor),
                                     moviesCollectionView.bottomAnchor.constraint(equalTo: bottomAnchor)])`

And while I'm at it if somebody could elaborate a bit more on this delegate function.

                        pasteboardWriterForItemAt indexPath: IndexPath) -> NSPasteboardWriting? {
        let pasteBoardItem = NSPasteboardItem()
        pasteBoardItem.setString("\(indexPath.item)", forType: .string)
        return pasteBoardItem
    }

The drag and drop is only locally but nothing works if I don't return a pasteboard item? and if needed, how do you go about posting a custom object?

If somebody has an idea I would greatly appreciate it. Happy to post other code that would help with the debugging

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