UIDragItem causes memory leak when Context Menu has been initialised

Question

Created Mar ’21

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Hi!

I have a CollectionView with Drag and Drop and Context Menu functionality. There's a memory leak caused by returned [UIDragItem] array in ItemsForBeginning method when I initialise cell's context menu.

Objects are being kept in memory when I pop to rootViewController. All is OK though when drag session was happened.

I've ended up commenting out everything, keeping blank UIDragItem and problem is still there:

Code Block     func collectionView(_ collectionView: UICollectionView, itemsForBeginning session: UIDragSession, at indexPath: IndexPath) -> [UIDragItem] {
        let dragItem = UIDragItem(itemProvider: NSItemProvider(object: "" as NSString))
        return [dragItem]
    }

Does anybody experience this?
Looks like it's a UIKit bug...

Please help!

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Answer 1

hacknicity OP

Dec ’21

I also see this issue with both collection views and table views. I'm using Objective-C on Xcode 13.2 release candidate with iOS 15.2 (19C51).

In order to get a leak I have to:

return a non-empty array from the table/collection view delegate that asks for itemsForBeginningDragSession:
return a UIContextMenuConfiguration from the table/collection view delegate that asks for the contextMenuConfigurationForRow/ItemAtIndexPath
long press on the cell and NOT drag
dismiss my view controller that has the table/collection view

I then see that the collection/table view is leaked (and, in turn, its cached table view cells and the diffable data source object)

I have found that I do NOT get a leak if I do any one of these things:

return an empty array from the table/collection view delegate that asks for itemsForBeginningDragSession:
return nil from the table/collection view delegate that asks for the contextMenuConfigurationForRow/ItemAtIndexPath
after the long press, begin dragging

It does not matter whether the drag is dropped or cancelled, just starting to drag will prevent the leak.

Returning a non-nil UIContextMenuConfiguration which has blocks for its previewProvider and actionProvider that return nil (which is visually the same as returning a nil configuration - no context menu is shown on a long press) will still leak.

0

Answer 2

pook OP

Feb ’22

Did you solve this problem?

0