viewer.setRootEditPart(root);
viewer.setKeyHandler(new GraphicalViewerKeyHandler(viewer));
viewer.setEditPartFactory(new GraphicalPartFactory());
viewer.getControl().setBackground(ColorConstants.listBackground);
ContextMenuProvider provider = new GraphContextMenuProvider(viewer, getActionRegistry());
viewer.setContextMenu(provider);
getSite().registerContextMenu(CONTEXT_MENU_ID, provider, viewer);
}