@Override
public EditPart getTargetEditPart(Request request) {
  if (request instanceof SelectionRequest) {
  Point location = ((SelectionRequest) request).getLocation();
  getFigure().translateToAbsolute(location);
  List<IGraphicalEditPart> children = getChildren();
  for (IGraphicalEditPart child : children) {
     Rectangle bounds = child.getFigure().getBounds().getCopy();
     getFigure().translateToAbsolute(bounds);
     if (bounds.expand(20, 20).contains(location)) {
       return child;
      }
   }
}
return super.getTargetEditPart(request);