void showFinishScreen()
{
// stop spawn objects and clear scene
isFinished = true;
TargetsFactory.ReleaseAllTargets();
// hide texts
scoreText.gameObject.SetActive(false);
timeLeftText.gameObject.SetActive(false);
timePassedText.gameObject.SetActive(false);
lifesText.gameObject.SetActive(false);
// show final dialog
if (gameObject.GetComponent <FinalDialog> () == null)
{
gameObject.AddComponent <FinalDialog> ();
}
}
