Register commandHandler with EventList in a Nattable with Filters

Question

As a suggestion from question Nattable add row command I tried to register a command handler with an EventList.

But since the Eventlist is wrapped by a FilterList which acts as BodyDataProvider I could not create a DataLayer based in EventList from which I could register my CommmandHandler.

The starting point is the previous question to define a BodyLayerStack with the following:

class BodyLayerStack extends AbstractLayerTransform {
    //AncolabMaterial is the model to show at the natTable
    private final EventList<AncolabMaterial> filterList;
    private final IDataProvider bodyDataProvider;
    private final SelectionLayer selectionLayer;
    public BodyLayerStack(List<AncolabMaterial> input_values_list, IColumnPropertyAccessor<AncolabMaterial> columnPropertyAccessor) {
        EventList<AncolabMaterial> eventList = GlazedLists.eventList(input_values_list);
        TransformedList<?, ?> rowObjectsGlazedList = GlazedLists.threadSafeList(eventList);
        SortedList<?> sortedList = new SortedList<>(rowObjectsGlazedList, null);
        this.filterList = new FilterList<AncolabMaterial>((EventList<AncolabMaterial>) sortedList);
        this.bodyDataProvider = new ListDataProvider<AncolabMaterial>(filterList, columnPropertyAccessor);
        DataLayer bodyDataLayer = new DataLayer(getBodyDataProvider());
        //Other layers stacked
        GlazedListsEventLayer<?> glazedListsEventLayer = new GlazedListsEventLayer<AncolabMaterial>(bodyDataLayer, this.filterList); 
        this.selectionLayer = new SelectionLayer(glazedListsEventLayer, false);
        //...
    }
}

I have tried the following:

DataLayer dataLayer = new DataLayer(
    new ListDataProvider<AncolabMaterial>(eventList, columnPropertyAccessor));

But since DataLayer wraps the IDataProvider, and serves as the data source for all other layers, If I sets the EvenList as the IDataProvider of the DataLayer then filterlList is not working properly. i.e. this.filterList is not the base of the bodyDataProvider.

I have not find at nattable_examples -> tutorial examples -> GlazedLists -> Filter any other BodyLayerStack configuration different than the above.

Answer 1

There seems to be a big misunderstanding with regards to the list instances. If you want to use the filter functionality the shown BodyLayerStack is correct. You have to use the FilterList in the IDataProvider. There is absolutely now reason to change that!

For the command handler you need to use the base EventList instance. Of course that does not work if you use the list that you get from the IDataProvider. You need to provide the access to the EventList in another way. From the snippets you show in this and in the other related post, I don't see a reason why you access the underlying list via IDataProvider, but as you already noticed, that does not work. You need to change your code structure.