private void ObserveIndexChanges(IObservable <Unit> databaseChanged)
{
if (Database.Value != null)
{
Database.Value.IndexChanges
.Where(n => n.Name.Equals(CollectionsIndex, StringComparison.InvariantCulture))
.SampleResponsive(TimeSpan.FromSeconds(2))
.TakeUntil(Unloaded.Merge(databaseChanged))
.ObserveOnDispatcher()
.Subscribe(__ => RefreshCollectionsList());
}
}