private IEnumerator ShowMenu(UIFader fader, VRTrackerTag tag)
        {
            yield return(StartCoroutine(fader.InteruptAndFadeIn()));

            yield return(StartCoroutine(tag.WaitForAssignation()));

            if (tag.IDisAssigned)
            {
                transform.GetComponent <AudioSource> ().Play();
            }
            yield return(StartCoroutine(fader.InteruptAndFadeOut()));
        }