sheet = (JComponent) dialog.getContentPane();
sheet.setBackground (Color.red);
glass.setLayout (new GridBagLayout());
sheet.setBorder (new LineBorder(Color.black, 1));
glass.removeAll();
GridBagConstraints gbc = new GridBagConstraints();
gbc.anchor = GridBagConstraints.NORTH;
glass.add (sheet, gbc);
gbc.gridy=1;
gbc.weighty = Integer.MAX_VALUE;
glass.add (Box.createGlue(), gbc);
glass.setVisible(true);
return sheet;