/// <summary>
 /// Add a new screen
 /// </summary>
 /// <param name="screen">GameScreen to add</param>
 /// <param name="name">Name for the screen</param>
 /// <param name="enable">Enable the screen</param>
 public void AddScreen(GameScreen screen, string name, bool enable)
 {
     screen.spriteBatch = spriteBatch;
     screen.Manager     = this;
     _screens.Add(screen);
     _screenRef[name] = _screens.Count - 1;
     screen.Initialise();
     if (_contentLoaded)
     {
         screen.LoadContent();
     }
     if (!enable)
     {
         screen.Disable();
     }
 }
 /// <summary>
 /// Add a new screen
 /// </summary>
 /// <param name="screen">GameScreen to add</param>
 /// <param name="name">Name for the screen</param>
 /// <param name="enable">Enable the screen</param>
 public void AddScreen(GameScreen screen,string name,bool enable)
 {
     screen.spriteBatch=spriteBatch;
     screen.Manager=this;
     _screens.Add(screen);
     _screenRef[name]=_screens.Count-1;
     screen.Initialise();
     if (_contentLoaded)
         screen.LoadContent();
     if (!enable)
         screen.Disable();
 }