UICollectionViewDiffableDataSource and Reordering Custom Cells???

How are developers supposed to support interactive reordering of custom cells in UICollectionViews that use UICollectionViewDiffableDataSource?

collectionView.beginInteractiveMovementForItem(at: iPath)
collectionView.updateInteractiveMovementTargetPosition(target)
collectionView.endInteractiveMovement()

Will work maybe 70% of the time, but the other 30% of the time when calling endInteractiveMovement() the dataSource.snapshot does not properly reflect the updated state.

Obviously there is a way to make this work if we use UICollectionViewListCells and the .reorder accessory, but that's not an acceptable solution.

Please advise.

Up vote post of nickneedsaname Down vote post of nickneedsaname
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nickneedsaname
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  • Update:        dataSource.reorderingHandlers.willReorder = { [weak self] (transaction) in         guard let self = self else {           return         }         DispatchQueue.main.async {           self.dataSource.apply(transaction.finalSnapshot, animatingDifferences: true) {                         }         }       }

    This doesn't even work!!!!!!!!!!!!!

    The following does work:       dataSource.reorderingHandlers.didReorder = { [weak self] (transaction) in         guard let self = self else {           return         }         self.collectionItems = transaction.finalSnapshot.itemIdentifiers(inSection: 0)       }

    But updating the collection to the proper state after it's supposed to be in the proper state seems wrong. I also find the amount of blinking both solutions incur to be unacceptable.

    —
    nickneedsaname
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