static JPanel vstack2(O... parts) {
  JPanel panel = new JPanel(new GridBagLayout);
  new GridBagConstraints gbc;
  gbc.weightx = 1;
  gbc.fill = GridBagConstraints.HORIZONTAL;
  gbc.gridwidth = GridBagConstraints.REMAINDER;
  smartAddWithLayout(panel, gbc, parts);
  //gbc = (GridBagConstraints) gbc.clone();
  //gbc.fill = GridBagConstraints.BOTH;
  gbc.weighty = 1;
  panel.add(Box.createRigidArea(new Dimension(0, 0)), gbc);
  ret panel;
}