Hi all,

I'm coding a graphical interface for small screen touchscreen PC composed of
menus and submenus. As the look of it must be fancy, there is a background
image.

I'd like a status bar on top displaying informations (like is there a CD or
DVD in the tray, time/date and so on). This status bar is darkened but
still transparent, and must be present on all menus and screens.

So the main window is a JFrame with BorderLayout content pane. At the center
a card layout displays the different screens and at the north there is this
status bar :
public class StatusBarJPanel extends javax.swing.JPanel {
private JLabel jLabelDateTime;
private LabelDateTimeTimer timer;
private JLayeredPane layeredPane;

public StatusBarJPanel() {
 super();
 init();
}

private void init() {
 layeredPane = new JLayeredPane();
 layeredPane.setLayout(new BorderLayout());
 layeredPane.setOpaque(true);
 layeredPane.setBackground(new Color(0, 0, 0, 130));
 this.add(layeredPane, BorderLayout.NORTH);

 try {
  this.setPreferredSize(new java.awt.Dimension(640, 40));
  layeredPane.setPreferredSize(new java.awt.Dimension(640, 40));
 
  jLabelDateTime = new JLabel();
  timer = new LabelDateTimeTimer(jLabelDateTime);
  layeredPane.add(jLabelDateTime, BorderLayout.EAST);
  jLabelDateTime.setForeground(Color.WHITE);
  jLabelDateTime.setFont(new Font("Helvetica", Font.BOLD, 18));
  jLabelDateTime.addPropertyChangeListener(new PropertyChangeListener() {
   // to avoid odd background repainting after time change
   public void propertyChange(PropertyChangeEvent evt) {
    layeredPane.repaint();
    layeredPane.getParent().repaint();
   }
  });
 
  JLayeredPane iconPane = new JLayeredPane();
  iconPane.setLayout(new FlowLayout());
  layeredPane.add(iconPane, BorderLayout.WEST);
  ImageIcon dvd =
   new ImageIcon(
    getClass().getClassLoader().getResource(
     "skins/tst/dvd_mount.png"));
  JLabel dvdIcon = new JLabel(dvd);
  iconPane.add(dvdIcon);
  ImageIcon gprs =
   new ImageIcon(
    getClass().getClassLoader().getResource(
     "skins/tst/gprs.png"));
  JLabel gprsIcon = new JLabel(gprs);
  iconPane.add(gprsIcon);
 
 } catch (Exception e) {
  e.printStackTrace();
 }
}
}
(this is just a prototype to see if what we need is feasible, so quick and
dirty code...)

Two questions :
- Is there another simpler design to avoid LayeredPane + JPanel (this is to
repaint the background after some elements of the status bar change) ?
- There is a small border at the top of the window where the LayeredPane is
not visible, so there is a small stipe at the top of the window not colored
by the layered pane. I tried to add an empty border to the JPane, put the
LayeredFrame at the north, but the stripe is still there. Do you see a
workaround ?

Thank you for your answers.

Best regards,

Tobias