protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
//_spriteBatch = new SpriteBatch(GraphicsDevice);
var guiDemo = new GuiDemo(this);
_gui = guiDemo.CreateGui();
_keyboardManager._oldKeyboardState = Keyboard.GetState();
_oldMouseState = Mouse.GetState();
_oldGamePad = GamePad.GetState(PlayerIndex.One);
_index = 0;
_currentScreen = _currentScreens[_index];
_currentScreen.Init(this);
base.LoadContent();
}