Bug 126658 [CommonNavigator] [DND] Complete definition of DND API
bundles/org.eclipse.ui.navigator.resources/src/org/eclipse/ui/internal/navigator/resources/actions/OpenActionProvider.java
if (aConfig.getViewSite() instanceof ICommonViewerWorkbenchSite) {
			viewSite = (ICommonViewerWorkbenchSite) aConfig.getViewSite();
			openFileAction = new OpenFileAction(viewSite.getPage());
			contribute = true;
		}
	}
	public void fillContextMenu(IMenuManager aMenu) {
		if (!contribute || getContext().getSelection().isEmpty())
			return;
		IStructuredSelection selection = (IStructuredSelection) getContext()
				.getSelection();
		openFileAction.selectionChanged(selection);
		if (openFileAction.isEnabled())
			aMenu.insertAfter(ICommonMenuConstants.GROUP_OPEN, openFileAction);
		addOpenWithMenu(aMenu);
	}
	public void fillActionBars(IActionBars theActionBars) {
		if (!contribute)
			return;
		IStructuredSelection selection = (IStructuredSelection) getContext()
				.getSelection();
		if (selection.size() == 1
				&& selection.getFirstElement() instanceof IFile) {
			openFileAction.selectionChanged(selection);
			theActionBars.setGlobalActionHandler(ICommonActionConstants.OPEN,
					openFileAction);
		}
	}
	private void addOpenWithMenu(IMenuManager aMenu) {
		IStructuredSelection ss = (IStructuredSelection) getContext()