The filter is not applied when changing the original collection

[gserrg]

If we stay inin the “Photos with objects” filtering mode, and then start processing the next batch of photos, then upon completion this list is not updated, you need to manually enable the display of all photos and then return to the filter.

In short, the filter is not automatically applied when updating the original image collection. In order for the filter to be updated, you need to call it explicitly.

[gosha20777]

This is because ReactiveUI Dynamic.Data is able to handle filter changes only when the target property that sets the filter changes. But the filter does not track collection changes.

Look at example here:

SourceList<PhotoViewModel> _photos { get; set; } = new SourceList<PhotoViewModel>();
private ReadOnlyObservableCollection<PhotoViewModel> _photoCollection;
...
public MainWindowViewModel(Window window)
{
    ...
    var typeFilter = this
                .WhenValueChanged(x => x.FilterType)
                .Select(TypeFilter);
    _photos.Connect()
                .Filter(typeFilter)
                .ObserveOn(RxApp.MainThreadScheduler)
                .Bind(out _photoCollection)
                .DisposeMany()
                .Subscribe();
    ...
}
...

private Func<PhotoViewModel, bool> TypeFilter(int fitlerType)
 {
    switch (fitlerType)
    {
        case Any:
            return x => true;
        case WithObject:
            return x => x.Photo.Attribute == Attribute.WithObject;
        case Favorite:
            return x => x.Photo.Attribute == Attribute.Favorite;
        default:
            throw new Exception("invalid filter");
    }
}

So i really do not know how to make it update filter when the _photos source list changed. @worldbeater may be you knows?

[gosha20777]

@gserrg I am find a temporary solution -) I simply can add button with 🔄 same sign "update" in the left of filter. and you can click in it to update the collection)