java - How do I determine the position of the system tray on the screen?

Question

So I want to display a JPopupMenu whenever the user clicks the icon in the system tray. However, the task bar could be anywhere on the screen - bottom , top , right, left.

How do I determine where the sys tray is so that I can display the popup?
getX() and getY() can get the coordinates of the click. Can some math be done to display the popup properly ?

A simple explanation and sample code will be appreciated.

Also, if the task bar is hidden, will an exception be generated when I add TrayIcon to the SystemTray?

Answer 1

There's no real way to do this within Swing natively, however, you can derive the possible location with the following...

GraphicsDevice gd = GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice();
Rectangle bounds = gd.getDefaultConfiguration().getBounds();
Insets insets = Toolkit.getDefaultToolkit().getScreenInsets(gd.getDefaultConfiguration());

Rectangle safeBounds = new Rectangle(bounds);
safeBounds.x += insets.left;
safeBounds.y += insets.top;
safeBounds.width -= (insets.left + insets.right);
safeBounds.height -= (insets.top + insets.bottom);

System.out.println("Bounds = " + bounds);
System.out.println("SafeBounds = " + safeBounds);

Area area = new Area(bounds);
area.subtract(new Area(safeBounds));
System.out.println("Area = " + area.getBounds());

Which outputs

Bounds = java.awt.Rectangle[x=0,y=0,width=2560,height=1600]
SafeBounds = java.awt.Rectangle[x=0,y=40,width=2560,height=1560]
Area = java.awt.Rectangle[x=0,y=0,width=2560,height=40]

For my system (note, my task bar is at the top of the screen)

Updated

As demonstrated in my previous answer to your question about tray icons...

public class TestTaskIcon {

  public static void main(String[] args) {

    EventQueue.invokeLater(new Runnable() {
      @Override
      public void run() {

        Image img = null;
        try {
          img = ImageIO.read(new File("floppy_disk_red.png"));
        } catch (IOException e) {
          e.printStackTrace();
        }
        TrayIcon ti = new TrayIcon(img, "Tooltip");
        ti.addMouseListener(new MouseAdapter() {
          @Override
          public void mouseClicked(MouseEvent e) {
            Rectangle bounds = getSafeScreenBounds(e.getPoint());
            JPopupMenu popup = new JPopupMenu();
            popup.add(new JLabel("hello"));

            Point point = e.getPoint();

            int x = point.x;
            int y = point.y;
            if (y < bounds.y) {
              y = bounds.y;
            } else if (y > bounds.y + bounds.height) {
              y = bounds.y + bounds.height;
            }
            if (x < bounds.x) {
              x = bounds.x;
            } else if (x > bounds.x + bounds.width) {
              x = bounds.x + bounds.width;
            }

            if (x + popup.getPreferredSize().width > bounds.x + bounds.width) {
              x = (bounds.x + bounds.width) - popup.getPreferredSize().width;
            }
            if (y + popup.getPreferredSize().height > bounds.y + bounds.height) {
              y = (bounds.y + bounds.height) - popup.getPreferredSize().height;
            }
            popup.setLocation(x, y);
            popup.setVisible(true);
          }
        });
        try {
          SystemTray.getSystemTray().add(ti);
        } catch (AWTException ex) {
          Logger.getLogger(TestTaskIcon.class.getName()).log(Level.SEVERE, null, ex);
        }
      }
    });
  }

  public static Rectangle getSafeScreenBounds(Point pos) {

    Rectangle bounds = getScreenBoundsAt(pos);
    Insets insets = getScreenInsetsAt(pos);

    bounds.x += insets.left;
    bounds.y += insets.top;
    bounds.width -= (insets.left + insets.right);
    bounds.height -= (insets.top + insets.bottom);

    return bounds;

  }

  public static Insets getScreenInsetsAt(Point pos) {
    GraphicsDevice gd = getGraphicsDeviceAt(pos);
    Insets insets = null;
    if (gd != null) {
      insets = Toolkit.getDefaultToolkit().getScreenInsets(gd.getDefaultConfiguration());
    }
    return insets;
  }

  public static Rectangle getScreenBoundsAt(Point pos) {
    GraphicsDevice gd = getGraphicsDeviceAt(pos);
    Rectangle bounds = null;
    if (gd != null) {
      bounds = gd.getDefaultConfiguration().getBounds();
    }
    return bounds;
  }

  public static GraphicsDevice getGraphicsDeviceAt(Point pos) {

    GraphicsDevice device = null;

    GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
    GraphicsDevice lstGDs[] = ge.getScreenDevices();

    ArrayList<GraphicsDevice> lstDevices = new ArrayList<GraphicsDevice>(lstGDs.length);

    for (GraphicsDevice gd : lstGDs) {

      GraphicsConfiguration gc = gd.getDefaultConfiguration();
      Rectangle screenBounds = gc.getBounds();

      if (screenBounds.contains(pos)) {

        lstDevices.add(gd);

      }

    }

    if (lstDevices.size() > 0) {
      device = lstDevices.get(0);
    } else {
      device = ge.getDefaultScreenDevice();
    }

    return device;

  }
}