/// <summary>
        /// 
        /// </summary>
        /// <param name="screen"></param>
        /// <param name="isInitialized"></param>
        public void AddScreen(Screen screen, bool isInitialized)
        {
            screen.ScreenManager = this;

            if (!isInitialized)
            {
                screen.Initialize();
                screen.LoadContent();
            }

            screens.Add(screen);
        }