void DisplayPauseGameScoreBoard()
 {
     activeBird.Stop();
     endGameTextObject.SetActive(false);
     DisplayEndGameScoreBoard();
     UpdateMedal(GameController.instance.GetHightScore());
     replayBtn.onClick.RemoveAllListeners();
     replayBtn.onClick.AddListener(() =>
     {
         activeBird.Resume();
         GameController.instance.ResetGameSpeed();
         endGameTextObject.SetActive(true);
         endGameScoreBoard.SetActive(false);
         replayBtn.onClick.RemoveAllListeners();
         replayBtn.onClick.AddListener(Replay);
     });
 }
    void Awake()
    {
        int        selectedBird         = GameController.instance.GetSelectedBird();
        GameObject activeBirdGameObject = birds[selectedBird];

        activeBirdGameObject.SetActive(true);

        activeBird = activeBirdGameObject.GetComponent <BirdScripts>();
        activeBird.RegisterOnEndGameCallBack(DisplayEndGameScoreBoard);
        activeBird.RegisterScoreCallBack(WinAScore);

        flapBtn.onClick.AddListener(Flap);
        menuBtn.onClick.AddListener(GoToMenu);
        replayBtn.onClick.AddListener(Replay);
        pauseBtn.onClick.AddListener(DisplayPauseGameScoreBoard);
        guideBtn.onClick.AddListener(() =>
        {
            guideBtn.gameObject.SetActive(false);
            GameController.instance.ResetGameSpeed();
            activeBird.Resume();
        });
    }