static JPanel jcenteredbuttons_withPopDown(int maxToShow, O... params) {
  new L<JComponent> l;
  new L popDownParams;
  for (int i = 0; i < l(params); i += 2)
    if (params[i] != null) {
      if (l(l) >= maxToShow) {
        popDownParams.add((S) params[i]);
        popDownParams.add(params[i+1]);
      } else
        if (params[i] instanceof JComponent)
          l.add((JComponent) params[i--]);
        else
          l.add(jbutton((S) params[i], params[i+1]));
    }
  if (nempty(popDownParams))
    l.add(jPopDownButton_noText(toObjectArray(popDownParams));
  ret jcenteredline(l);
}