public void StartGame()
        {
            gamePlayScreen = new GamePlayScreen(this);
            currentScreen  = Screen.GamePlayScreen;

            startScreen    = null;
            gameOverScreen = null;
        }
        public void StartScreen()
        {
            startScreen   = new StartScreen(this);
            currentScreen = Screen.StartScreen;

            gameSelectScreen = null;
            gameOverScreen   = null;
            gamePlayScreen   = null;
        }
        protected override void LoadContent()
        {
            spriteBatch = new SpriteBatch(GraphicsDevice);
            TextureManager.LoadContent(Content);
            FontManager.LoadContent(Content);
            MusicManager.LoadContent(Content);
            SoundEffectManager.LoadContent(Content);

            startScreen   = new StartScreen(this);
            currentScreen = Screen.StartScreen;
            MediaPlayer.Play(MusicManager.MenyMusic);
            MediaPlayer.IsRepeating = true;

            base.LoadContent();
        }