I have a couple of (older) UIKit-based Apps using UISplitViewController on the iPad to have a two-column layout. I'm trying to edit the App so it will shows the left column as sidebar with liquid glass effect, similar to the one in the "Settings" App of iPadOS 26. But this seems to be almost impossible to do right now.
"out of the box" the UISplitViewController already shows the left column somehow like a sidebar, with some margins to the sides, but missing the glass effect and with very little contrast to the background. If the left column contains a UITableViewController, I can try to get the glass effect this way within the UITableViewController:
tableView.backgroundColor = .clear
tableView.backgroundView = UIVisualEffectView(effect: UIGlassContainerEffect())
It is necessary to set the backgroundColor of the table view to the clear color because otherwise the default background color would completely cover the glass effect and so it's no longer visible.
It is also necessary to set the background of all UITableViewCells to clear.
If the window is in the foreground, this will now look very similar to the sidebar of the Settings App. However if the window is in the back, the sidebar is now much darker than the one of the Settings App. Not that nice looking, but for now acceptable.
However whenever I navigate to another view controller in the side bar, all the clear backgrounds destroy the great look, because the transition to the new child controller overlaps with the old parent controller and you see both at the same time (because of the clear backgrounds).
What is the best way to solve these issues and get a sidebar looking like the one of the Settings App under all conditions?
