Game Center on Monotouch

Hi everyone,

I'm trying to implement Game Center into my game but i have problems with it.

Here is my Main.cs code : http://snipt.org/APD7

And here is the superclass of that Main.cs : https://github.com/libgdx/libgdx/blob/master/backends/gdx-backend-iosmonotouch/src/com/badlogic/gdx/backends/ios/IOSApplication.java

I'm trying to use this https://github.com/xamarin/monotouch-samples/blob/master/GameCenterSample/GameCenterSample/MainViewController.cs example but i can't see any authenticate window in my game.

How can i fix it?

Thanks in advance