Problem restoring the game preffered buffer size after navigating from a XAML page. Monogame

Question

I have implemented to my game a simple leaderboard and submit score pages, which are pages in XAML. I used PreferredBackBufferHeight/Width to set the buffer to be equaly on all devices, whether their screen size is 5 inch, 4.7 or whatever size. Though I thought the problem was solved, now, when I was testing my game on emulator for bigger devices, I encountered a problem when returning back to game page from the xaml page. Let me show you some pics, and you will understand what I am talking about:

Testing on Emulator 4.7 inch:

1) Before entering the leaderboard xaml page (everything normal):

2) After exiting from xaml leaderboard page:

Even if I tried to put the PreferredBackBufferHeight/Width in the function that I call to exit from the leaderboard page, it didn't change anything... :

private void NavigateBackToMain()
    {
        var app = App.Current as App;

        if (app.GamePage == null) app.GamePage = new GamePage(string.Empty);
        Game1.statics.graphics.SupportedOrientations = Microsoft.Xna.Framework.DisplayOrientation.LandscapeRight | Microsoft.Xna.Framework.DisplayOrientation.LandscapeLeft;
        Game1.statics.graphics.PreferredBackBufferHeight = Constants.PrefferedBufferHeight;
        Game1.statics.graphics.PreferredBackBufferWidth = Constants.PrefferedBufferWidth;

        Window.Current.Content = app.GamePage;
    }

What can I do about my problem?

Answer 1

I think you solved your problem already, but for any future visitors to the site here it is as well.

The problem that you were having was that you never called Graphics.ApplyChanges() after you changed your graphics settings. This resulted in the screen not actually being updated, and the smaller screen after exiting is due to an odd orientation bug.

Here's what your code should look like:

private void NavigateBackToMain()
{
    ....
    Game1.statics.graphics.SupportedOrientations = Microsoft.Xna.Framework.DisplayOrientation.LandscapeRight | Microsoft.Xna.Framework.DisplayOrientation.LandscapeLeft;
    Game1.statics.graphics.PreferredBackBufferHeight = Constants.PrefferedBufferHeight;
    Game1.statics.graphics.PreferredBackBufferWidth = Constants.PrefferedBufferWidth;

    Game1.statics.graphics.ApplyChanges();
    ....
}