public async Task GetTicks() { // Account feed ticks List <TTFeedTick> ticks; if (string.IsNullOrEmpty(TicksFilter)) { ticks = await _client.GetAllTicksAsync(); } else { ticks = await _client.GetTickAsync(TicksFilter); } Ticks = ticks != null ? new ObservableCollection <FeedTickView>(ticks.Select(t => new FeedTickView(t))) : null; }