Handling bottom navigation bar on Windows 10 Mobile - xamarin

Question

In my Xamarin.Forms app I have a button at the bottom. This button is hidden on a Windows 10 Mobile phone. Isn't there a setting were the size of my page is adapting to the available size? In such a case the height of my page would decrease if the navigation bar is shown, and it would increase if the navigation bar is hidden.
I saw solutions suggesting to programmaticaly hidding the navigation bar. E.g.
ApplicationView.GetForCurrentView().TryEnterFullScreenMode();
Where should it be placed? I put it in the App.xaml.cs before rootFrame.Navigate in OnLaunched. If I run the app on my local machine it changed to fullscreen. On the mobile phone the navigation bar was hidden, but there remained a white area at the bottom.
Furthermore I tried
ApplicationView.GetForCurrentView().FullScreenSystemOverlayMode = FullScreenSystemOverlayMode.Minimal;
but I don't see something different.
How should a developer handle the navigation bar without hiding the content beneath it?

Answer 1

This seems to fix the issue:
ApplicationView.GetForCurrentView().SuppressSystemOverlays = true;
The result is that the navigation bar isn't shown when starting the app. The user has the possibility to show the navigation bar with a swipe up. Here the page automatically resizes as desired.
I put it in the App.xaml.cs in the OnLaunched method:
protected override void OnLaunched(LaunchActivatedEventArgs e)
{
Frame rootFrame = Window.Current.Content as Frame;
// Do not repeat app initialization when the Window already has content,
// just ensure that the window is active
if (rootFrame == null)
{
// Create a Frame to act as the navigation context and navigate to the first page
rootFrame = new Frame();
rootFrame.NavigationFailed += OnNavigationFailed;
Xamarin.Forms.Forms.Init(e);
if (e.PreviousExecutionState == ApplicationExecutionState.Terminated)
{
//TODO: Load state from previously suspended application
}
// Place the frame in the current Window
Window.Current.Content = rootFrame;
}
if (rootFrame.Content == null)
{
// When the navigation stack isn't restored navigate to the first page,
// configuring the new page by passing required information as a navigation
// parameter
ApplicationView.GetForCurrentView().SuppressSystemOverlays = true;
rootFrame.Navigate(typeof(MainPage), e.Arguments);
}
// Ensure the current window is active
Window.Current.Activate();
}

Answer 2

You can also use:
ApplicationView.GetForCurrentView().SetDesiredBoundsMode(ApplicationViewBoundsMode.UseVisible);
In the App.xaml.cs file for UWP in the onLauched function like this:
protected override void OnLaunched(LaunchActivatedEventArgs e)
{
if (System.Diagnostics.Debugger.IsAttached)
{
this.DebugSettings.EnableFrameRateCounter = true;
}
Frame rootFrame = Window.Current.Content as Frame;
// Do not repeat app initialization when the Window already has content,
// just ensure that the window is active
if (rootFrame == null)
{
// Create a Frame to act as the navigation context and navigate to the first page
rootFrame = new Frame();
rootFrame.NavigationFailed += OnNavigationFailed;
Xamarin.Forms.Forms.Init(e);
if (e.PreviousExecutionState == ApplicationExecutionState.Terminated)
{
//TODO: Load state from previously suspended application
}
// Place the frame in the current Window
Window.Current.Content = rootFrame;
}
if (rootFrame.Content == null)
{
// When the navigation stack isn't restored navigate to the first page,
// configuring the new page by passing required information as a navigation
// parameter
ApplicationView.GetForCurrentView().SetDesiredBoundsMode(ApplicationViewBoundsMode.UseVisible);
rootFrame.Navigate(typeof(MainPage), e.Arguments);
}
// Ensure the current window is active
Window.Current.Activate();
}
This will make sure your app stays inside the visible area, thus with no overlay from the bottom navigation bar.