public void WeakUnregisterTileHeightObserver(IHashTileHeightObserver observer)
{
weakHashObservers.RemoveAll(weakRef => !weakRef.TryGetTarget(out IHashTileHeightObserver target) ||
observer == target);
}
public void WeakRegisterTileHeightObserver(IHashTileHeightObserver observer)
{
weakHashObservers.RemoveAll(weakRef => !weakRef.TryGetTarget(out var target));
weakHashObservers.Add(new WeakReference <IHashTileHeightObserver>(observer));
}
