My selection listener doesn't seem to be registering properly - eclipse-rcp

Question

I am creating an Eclipse RCP application with multiple views. One of my views is a multi-page editor view. Each of those pages has a a master/details block. I need to register all of those TableViewers as selection providers for my other view to listen to.
After much research online, I came across this article about multiple selection providers in a single view. I followed the instructions to create this selection provider for multiple viewers.
class MyMultipleSelectionProvider implements ISelectionProvider {
private final ListenerList selectionListeners = new ListenerList();
private ISelectionProvider delegate;
private final ISelectionChangedListener selectionListener = new ISelectionChangedListener() {
#Override
public void selectionChanged(final SelectionChangedEvent event) {
if (event.getSelectionProvider() == AdaptabilityProfileSelectionProvider.this.delegate) {
fireSelectionChanged( event.getSelection() );
}
}
};
/**
* Sets a new selection provider to delegate to. Selection listeners
* registered with the previous delegate are removed before.
*
* #param newDelegate new selection provider
*/
public void setSelectionProviderDelegate(final ISelectionProvider newDelegate) {
if (this.delegate == newDelegate) {
return;
}
if (this.delegate != null) {
this.delegate.removeSelectionChangedListener(this.selectionListener);
}
this.delegate = newDelegate;
if (newDelegate != null) {
newDelegate.addSelectionChangedListener(this.selectionListener);
fireSelectionChanged(newDelegate.getSelection());
}
}
#Override
public void addSelectionChangedListener(final ISelectionChangedListener listener) {
this.selectionListeners.add(listener);
}
#Override
public ISelection getSelection() {
return this.delegate == null ? null : this.delegate.getSelection();
}
#Override
public void removeSelectionChangedListener(final ISelectionChangedListener listener) {
this.selectionListeners.remove(listener);
}
#Override
public void setSelection(final ISelection selection) {
if (this.delegate != null) {
this.delegate.setSelection(selection);
}
}
protected void fireSelectionChanged(final ISelection selection) {
fireSelectionChanged(this.selectionListeners, selection);
}
private void fireSelectionChanged(final ListenerList list, final ISelection selection) {
final SelectionChangedEvent event = new SelectionChangedEvent(this.delegate, selection);
final Object[] listeners = list.getListeners();
for (int i = 0; i < listeners.length; i++) {
final ISelectionChangedListener listener = (ISelectionChangedListener) listeners[i];
listener.selectionChanged(event);
}
}
}
I added a focusListener on all of the edior's viewers so they become the delegate:
tree.addFocusListener(new FocusAdapter() {
#Override
public void focusGained(final FocusEvent e) {
editor.getSelectionProvider().setSelectionProviderDelegate(MyEditorPage.this.treeViewer);
}
});
And I registered this as the selection provider for my editor:
site.setSelectionProvider( this.selectionProvider );
Then, within my view that needs to hear about the selection, I registered a selection listener for this editor:
getSite().getPage().addSelectionListener(MyEditor.ID, this.selectionListener);
When I run the application, I see that the delegate is being changed and the selection events are being fired. However, the listener list is empty.
I am never calling addSelectionChangeListener() directly. I was under the impression that that was what the selection service is for. Am I wrong? Should I be calling it? If so, when? If not, who is supposed to be adding the listener, and why isn't it happening?

Answer 1

If your code is based on FormEditor (or MultiPageEditorPart) then the selection provider is set to MultiPageSelectionProvider at the end of the init method. This may be overriding your site.setSelectionProvider call.
Using:
#Override
public void init(IEditorSite site, IEditorInput input)
throws PartInitException {
super.init(site, input);
site.setSelectionProvider(this.selectionProvider);
}
should make sure your provider is the one used.