private void UpdateSnapshot()
{
if (_newSnapshotRequired)
{
_snapshotLock.TryEnterWriteLock(Timeout.Infinite);
if (_newSnapshotRequired)
{
_baseSnapshot = new ImmutableCollectionImpl <T>(WriteCollection);
_newSnapshotRequired = false;
}
_snapshotLock.ExitWriteLock();
}
}
protected ConcurrentCollection(IEnumerable <T> Items)
{
_subscribers = new Dictionary <int, IObserver <NotifyCollectionChangedEventArgs> >();
WriteCollection = new ObservableCollection <T>(Items);
_baseSnapshot = new ImmutableCollectionImpl <T>(Items);
ViewModel = new ConcurrentCollectionViewModel <T>(this);
WriteCollection.CollectionChanged += HandleBaseCollectionChanged;
ViewModel.CollectionChanged += (sender, e) => CollectionChanged?.Invoke(sender, e);
}