VS 2019 16.11.0 Preview 1.0 - WindowInsetsControllerCompat

[gmck]

@jpobst As you predicted Xamarin.AndroidX.Core 1.5.0 has now been released, so I tested against the changes I made re the now closed issue xamarin/xamarin-android#5970.

In the AndroidR only version, the HideSystemUi was

Activity.Window.SetDecorFitsSystemWindows(false);
IWindowInsetsController windowInsetsController = Activity.Window.InsetsController;
windowInsetsController.Hide(WindowInsets.Type.StatusBars() | WindowInsets.Type.NavigationBars());                            
windowInsetsController.SystemBarsBehavior = (int)WindowInsetsControllerBehavior.ShowTransientBarsBySwipe;

For the WindowsCompat version, my initial attempt was

WindowCompat.SetDecorFitsSystemWindows(Activity.Window, false);
WindowInsetsControllerCompat windowInsetsControllerCompat = ViewCompat.GetWindowInsetsController(Activity.Window.DecorView);
windowInsetsControllerCompat.Hide(WindowInsetsCompat.Type.SystemBars() | WindowInsets.Type.NavigationBars());    
windowInsetsControllerCompat.SystemBarsBehavior = WindowInsetsControllerCompat.BehaviorShowTransientBarsBySwipe;

That works on AndroidR, but fails at runtime on anything lower than AndroidR because windowInsetsControllerCompat is always null.

Is that to be expected? The Android docs state Retrieves a WindowInsetsControllerCompat of the window this view is attached to, so I assumed it would work for all BuildVersionsCodes.

To get around it I create a WindowInsetsControllerCompat in the OnResume of the Fragment.

windowInsetsControllerCompat = new WindowInsetsControllerCompat(Activity.Window, Activity.Window.DecorView);

and then just use.

WindowCompat.SetDecorFitsSystemWindows(Activity.Window, false);
windowInsetsControllerCompat.Hide(WindowInsetsCompat.Type.SystemBars() | WindowInsets.Type.NavigationBars());    
windowInsetsControllerCompat.SystemBarsBehavior = WindowInsetsControllerCompat.BehaviorShowTransientBarsBySwipe;

WindowInsetsControllerCompat windowInsetsControllerCompat = ViewCompat.GetWindowInsetsController(Activity.Window.DecorView);

Appreciate your comments.

[gmck]

Another method I wanted to consider trying was

public static WindowInsetsControllerCompat toWindowInsetsControllerCompat(WindowInsetsController insetsController)

but it appears to be missing from Xamarin.AndroidX.Core 1.5.0

[jpobst]

public static WindowInsetsControllerCompat toWindowInsetsControllerCompat(WindowInsetsController insetsController)
but it appears to be missing from Xamarin.AndroidX.Core 1.5.0 

This seems to be available now, so it must have gotten fixed at some point since this was filed.