private async void ThumbnailDispatcherTimerOnTick(object sender, EventArgs eventArgs)
{
if (CollectionView.View.IsEmpty)
{
return;
}
int firstVisibleItem;
int lastVisibleItem;
_specialUniformGrid.GetVisibleRange(out firstVisibleItem, out lastVisibleItem);
lastVisibleItem += 1;
var items =
CollectionView.View.Cast <ClientViewModel>()
.Skip(firstVisibleItem > 1 ? firstVisibleItem - 1 : 0)
.Take(lastVisibleItem).ToList();
var totalImagesInMemory = _clientProvider.Clients.Where(x => x.Thumbnail != null && !items.Contains(x)).ToList();
if (totalImagesInMemory.Count > 60)
{
foreach (var clientViewModel in totalImagesInMemory.OrderBy(x => x.ThumbnailTimestamp).Take(75 - items.Count)
)
{
clientViewModel.Thumbnail = null;
}
}
try
{
await Task.Run(() => _clientProvider.GetClientScreens(items.Select(x => x.Id).ToList()));
}
catch (InvalidOperationException)
{
}
}
