I compiled one of my projects new and it seems, that it is no longer possible to change the colors of the bars with the following code. I'm using hosted builder and set the MinVersion to 11:
B4X:
Dim no As NativeObject = NavControl
no.GetField("navigationBar").RunMethod("setBarStyle:",Array(1))
no.GetField("navigationBar").RunMethod("setTintColor:", Array(no.ColorToUIColor(Colors.Red))) 'Iconfarbe'
no.GetField("navigationBar").RunMethod("setBarTintColor:", Array(no.ColorToUIColor(Colors.Grey))) 'Hintergrundfarbe'
Dim no As NativeObject = TabControl
no.GetField("tabBar").SetField("tintColor", no.ColorToUIColor(Colors.Blue)) 'active item
no.GetField("tabBar").SetField("unselectedItemTintColor", no.ColorToUIColor(Colors.Green)) 'inactive item
no.GetField("tabBar").SetField("barTintColor", no.ColorToUIColor(Colors.Yellow)) 'bar color