NatTable - Strange behavior when sorting - nattable

Question

I have a nattable with sort/filter capabilities based off of
http://www.eclipse.org/nattable/documentation.php?page=sorting
and example 6031_GlazedListsFilterExample.java
Initially my table has zero rows.
Scenario 1:
I view a CTabItem that contains a NatTable with no rows.
If I then populate the rows and click on the column headers, nothing happens (sorting seems disabled).
Scenario 2:
I do NOT view a CTabItem that contains the NatTable with no rows.
I then populate the rows
I then view the CTabItem that contains the NatTable which now has rows.
I click on the column headers and everything sorts as expected (sorting seems enabled)
Scenario 3:
I do NOT view a CTabItem that contains the NatTable with no rows.
I then populate the rows
I then view the CTabItem that contains the NatTable which now has rows.
I then remove all row data
I click on the column headers and everything sorts as expected (sorting seems enabled). * even though there are no rows I still see the up/down icons appear in the column header cell
Is there a reason that the column header actions are not 'updated' after the initial 'view' of the NatTable? In other words, it seems to take the presence/absence of rows into account for the rest of the tables life after the first time the NatTable is viewed, regardless of if the rows change.
Relevant Code sections shown below:
private CompositeLayer createExampleLayer(Collection<T> values,
IColumnPropertyAccessor<T> columnPropertyAccessor,
IDataProvider columnHeaderDataProvider, IConfigRegistry
configRegistry, Matcher<T> matcher) {
BodyLayerStack<T> bodyLayerStack = new BodyLayerStack<>(
values, columnPropertyAccessor);
// build the column header layer
DataLayer columnHeaderDataLayer = new
DefaultColumnHeaderDataLayer(columnHeaderDataProvider);
ILayer columnHeaderLayer = new
ColumnHeaderLayer(columnHeaderDataLayer, bodyLayerStack,
bodyLayerStack.getSelectionLayer());
SortHeaderLayer<T> sortHeaderLayer = new SortHeaderLayer<>
(columnHeaderLayer, new GlazedListsSortModel<T>
(bodyLayerStack.getSortedList(), columnPropertyAccessor,
configRegistry,
bodyLayerStack.getBodyDataLayer()), false);
FilterRowHeaderComposite<T> filterRowHeaderLayer = new
FilterRowHeaderComposite<>(
new DefaultGlazedListsFilterStrategy<T>
(bodyLayerStack.getFilterList(), columnPropertyAccessor,
configRegistry),
sortHeaderLayer, columnHeaderDataLayer.getDataProvider(),
configRegistry);
// Omitted code for rowHeaderLayer and cornerLayer
return new GridLayer(bodyLayerStack, filterRowHeaderLayer,
rowHeaderLayer, cornerLayer);
}
public BodyLayerStack(Collection<T> values,
IColumnPropertyAccessor<T> columnPropertyAccessor) {
eventList = GlazedLists.eventList(values);
TransformedList<T, T> rowObjectsGlazedList =
GlazedLists.threadSafeList(eventList);
this.sortedList = new SortedList<>(rowObjectsGlazedList, null);
// wrap the SortedList with the FilterList
this.filterList = new FilterList<>(sortedList);
this.bodyDataProvider = new ListDataProvider<>(this.filterList,
columnPropertyAccessor);
this.bodyDataLayer = new DataLayer(getBodyDataProvider());
// layer for event handling of GlazedLists and PropertyChanges
GlazedListsEventLayer<T> glazedListsEventLayer = new
GlazedListsEventLayer<>(bodyDataLayer, this.filterList);
this.selectionLayer = new SelectionLayer(glazedListsEventLayer);
ViewportLayer viewportLayer = new ViewportLayer(getSelectionLayer());
setUnderlyingLayer(viewportLayer);
}
private void enableSorting() {
this.nattable.addConfiguration(new SingleClickSortConfiguration());
}

Answer 1

Looks like the creation of your SortHeaderLayer is not correct. The last parameter of the GlazedListsSortModel needs to be the IDataLayer of the column header, not the body layer.
Changing your code to the following should make things work. It did at least on my side.
SortHeaderLayer<T> sortHeaderLayer = new SortHeaderLayer<>
(columnHeaderLayer, new GlazedListsSortModel<T>
(bodyLayerStack.getSortedList(), columnPropertyAccessor,
configRegistry,
columnHeaderDataLayer), false);