Catalyst app crashing on drag and drop from UITableView

Question

Created Jul ’20

Replies 4

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I have a UITableView and select multiple cells in edit mode - scrolling to select further cells then drag all selected cells to another view for the drop. This works as expected in IOS but in Catalyst I get a crash if the cells are currently not visible.
If I limit the selection and drag to cells that are visible on screen then drag performs fine.

This same code works perfectly in iPadOS.

Below is a print from console in Xcode

***********

2020-07-12 16:28:05.194476+1000 S * Terminating app due to uncaught exception 'NSRangeException', reason: 'NSDraggingItem.draggingFrame cannot be set to a zero size {{423.18359222412113, 427.42968353271488}, {0, 0}}'

Any suggestions?

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Answer 1

emreoktem OP

Aug ’20

It looks like to a Catalyst bug because it happens only when you drag a cell which is not visible on the screen and only on mac version of the app.

A workaround may be limiting the dragged cells by filtering them by the visible cells array of the tableview but of course this is not the expected behavior by the users.

Could you find any solution or a workaround to this problem?

0

Answer 2

Frameworks Engineer OP

Apple

Aug ’20

If you haven't already done so, please submit feedback using Feedback Assistant about this issue so we can investigate further. If you can attach a sample project, that would be most helpful to ensure we can reproduce the exact issue you are seeing.

0

Answer 3

stephenfromsyd OP

Aug ’20

I have submitted a Feedback Assistant and it is really easy to duplicate.
I don't have any workaround using drag and drop as cells not visible onscreen always crash the app on catalyst and not in iPadOS but I achieve what I want using the method I use in the iPhone app - which is less than ideal on a Mac!

0

Answer 4

stephenfromsyd OP

Oct ’20

I have good news - It seems that this bug has been fixed in OSX 11 Now working as expected

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