Game class constructor

Due to some UWP implementation details, MonoGame has to construct your Game derived class by itself, using a static initializer MonoGame.Framework.XamlGame<T>.Create(...).

In this situation, you have two main possibilities to create a Game derived class:

  1. Let XamlGame initialize your Game derived class using the default constructor
  2. Let XamlGame initialize your Game derived class using a custom constructor.

1. XamlGame uses the default constructor

With this logic, it isn't possible to inject dependencies through the constructor since the default constructor is called: var game = new T();

2. XamlGame uses a custom constructor

Why may you need this constructor?

Consider Game1 needs some dependencies such as an ISettingsRepository to get some values from each platform settings store. You would then implement an AndroidSettingsRepository and a UwpSettingsRepository, but you cannot construct those dependencies in Game1 itself, because they are platform dependent, so you'll have to inject them into its constructor.

For example, in a MainActivity on Android you would do:

_game = new Game1(
new AndroidTextFileImporter(Assets),
new AndroidSettingsRepository(this));

With the UWP implementation using XamlGame static initializer, you could do this:

_game = MonoGame.Framework.XamlGame<Game1>.Create(
() => new Game1(
    new UwpTextFileImporter(Assets),
    new UwpSettingsRepository(this)));

In this way, you tell the static initializer how you'd like to construct Game1.