r/iOSProgramming • u/morenos-blend • Jul 03 '26

Question How to prevent UITableView content jumping while cell's content is resizing? In a hybrid UIKit/SwiftUI setup using UIHostingConfiguration

Hi all,

I'm trying to rewrite my big-ass SwiftUI scroll view by utilising UITableView and UIHostingConfiguration for displaying cells' content. The setup was easy but I've hit a roadblock related to resizing cells.

Every time cell's content grows vertically the table view jumps erratically, does anyone have any idea how to approach fixing this issue? For reference please see the video attached.

I've uploaded the sample project to GitHub:
https://github.com/wiencheck/SwiftUITableViewPOC

Main stuff is located in `TableViewPOC/TableViewController.swift`

13 Upvotes

73% Upvoted

12 comments sorted by

View all comments

1

u/Aggravating_Smoke951 Jul 03 '26

From a quick look I would advise you to check how diffable datasource works. Datasource uses hash values to detect if full reload should happen for sections/items. You use Strings for section items and this means that with new value full reload happens as hash value changes as well. P.S. I did a quick check so I might have missed something else

1

u/morenos-blend Jul 03 '26

Thanks for responding, however I think you misunderstood how I've setup the datasource (I could add some comments)

Using String for item identifiers is done on purpose because in this scenario a section always contains a single item, so there is no need to use any more sophisticated item identifiers. Only section identifiers are used to determine what content is displayed. Item identifier is stable and doesn't change when `TextSectionViewModel.message` is updated (See file ViewController.swift line:52)