public void Attach(ITelephoneObserver observer) { _observers.Add(observer); }
public void Detatch(ITelephoneObserver observer) { _observers.Remove(observer); }
public TeleTubbie(ITelephoneObserver teleTubbies, TelephoneSubject telephone) { _teleTubbies = teleTubbies; telephone.Attach(_teleTubbies); }