codice:
		JPanel paneldesktop = new JPanel();
		paneldesktop.setLayout(null);
		paneldesktop.setBounds(0,0,desktop.getWidth()-20,desktop.getHeight()-100);
		paneldesktop.setVisible(true);
		if ( paneldatigara != null) {
			paneldesktop.add(paneldatigara);
		}
		paneldesktop.add(panelricerca);
		paneldesktop.add(panellottodigara);
		paneldesktop.add(panelarticolo);
		paneldesktop.add(panelprodotto);
		paneldesktop.add(panelriepilogo);
		
		JScrollPane scrolldesktop = new JScrollPane(paneldesktop);
		scrolldesktop.setLayout(null);
		scrolldesktop.setBounds(0,0,desktop.getWidth()-20,desktop.getHeight()-100);
		scrolldesktop.setVisible(true);

		desktop.add(scrolldesktop);
il pannello è tutto grigio, come se fosse vuto!