Bug 267242 [JFace] Add API to configure table and tree columns in a keyboard-accessible way
bundles/org.eclipse.ui.views/src/org/eclipse/ui/views/properties/PropertySheetPage.java
/**
     * Help context id
     * (value <code>"org.eclipse.ui.property_sheet_page_help_context"</code>).
     */
    public static final String HELP_CONTEXT_PROPERTY_SHEET_PAGE = "org.eclipse.ui.property_sheet_page_help_context"; 
    private PropertySheetViewer viewer;
    
    private PropertySheetSorter sorter;
    private IPropertySheetEntry rootEntry;
    private IPropertySourceProvider provider;
    private DefaultsAction defaultsAction;
    private FilterAction filterAction;
    private CategoriesAction categoriesAction;
    private CopyPropertyAction copyAction;
    private ICellEditorActivationListener cellEditorActivationListener;
    private CellEditorActionHandler cellEditorActionHandler;
    private Clipboard clipboard;
	private IWorkbenchPart sourcePart;
	/**
	 * Part listener which cleans up this page when the source part is closed.
	 * This is hooked only when there is a source part.
	 * 
	 * @since 3.2
	 */
	private class PartListener implements IPartListener {