updateChildren(ec, ev, vf);
{ if (! updateChildren(ec, ev, vf)) ec = null; }
  public void insertUpdate(DocumentEvent ev, Shape shape, ViewFactory vf)  {    Element el = getElement();    DocumentEvent.ElementChange ec = ev.getChange(el);    if (ec != null)      updateChildren(ec, ev, vf);    forwardUpdate(ec, ev, shape, vf);    updateLayout(ec, ev, shape);  }