//Create a panel and add components to it.
JPanel contentPane = new JPanel(new BorderLayout());
contentPane.setBorder(someBorder);
contentPane.add(someComponent, BorderLayout.CENTER);
contentPane.add(anotherComponent, BorderLayout.PAGE_END);
/** An application that requires no other files. */
public class GlassPaneDemo {
static private MyGlassPane myGlassPane;
/**
* Create the GUI and show it. For thread safety,
* this method should be invoked from the
* event-dispatching thread.
*/
private static void createAndShowGUI() {
//Create and set up the window.
JFrame frame = new JFrame("GlassPaneDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Start creating and adding components.
JCheckBox changeButton =
new JCheckBox("Glass pane \"visible\"");
changeButton.setSelected(false);
//Set up the content pane, where the "main GUI" lives.
Container contentPane = frame.getContentPane();
contentPane.setLayout(new FlowLayout());
contentPane.add(changeButton);
contentPane.add(new JButton("Button 1"));
contentPane.add(new JButton("Button 2"));
//Set up the menu bar, which appears above the content pane.
JMenuBar menuBar = new JMenuBar();
JMenu menu = new JMenu("Menu");
menu.add(new JMenuItem("Do nothing"));
menuBar.add(menu);
frame.setJMenuBar(menuBar);
//Set up the glass pane, which appears over both menu bar
//and content pane and is an item listener on the change
//button.
myGlassPane = new MyGlassPane(changeButton, menuBar,
frame.getContentPane());
changeButton.addItemListener(myGlassPane);
frame.setGlassPane(myGlassPane);
//Show the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
/**
* We have to provide our own glass pane so that it can paint.
*/
class MyGlassPane extends JComponent
implements ItemListener {
Point point;
//React to change button clicks.
public void itemStateChanged(ItemEvent e) {
setVisible(e.getStateChange() == ItemEvent.SELECTED);
}
protected void paintComponent(Graphics g) {
if (point != null) {
g.setColor(Color.red);
g.fillOval(point.x - 10, point.y - 10, 20, 20);
}
}
public void setPoint(Point p) {
point = p;
}
public MyGlassPane(AbstractButton aButton,
JMenuBar menuBar,
Container contentPane) {
CBListener listener = new CBListener(aButton, menuBar,
this, contentPane);
addMouseListener(listener);
addMouseMotionListener(listener);
}
}
/**
* Listen for all events that our check box is likely to be
* interested in. Redispatch them to the check box.
*/
class CBListener extends MouseInputAdapter {
Toolkit toolkit;
Component liveButton;
JMenuBar menuBar;
MyGlassPane glassPane;
Container contentPane;
public CBListener(Component liveButton, JMenuBar menuBar,
MyGlassPane glassPane, Container contentPane) {
toolkit = Toolkit.getDefaultToolkit();
this.liveButton = liveButton;
this.menuBar = menuBar;
this.glassPane = glassPane;
this.contentPane = contentPane;
}
public void mouseMoved(MouseEvent e) {
redispatchMouseEvent(e, false);
}
public void mouseDragged(MouseEvent e) {
redispatchMouseEvent(e, false);
}
public void mouseClicked(MouseEvent e) {
redispatchMouseEvent(e, false);
}
public void mouseEntered(MouseEvent e) {
redispatchMouseEvent(e, false);
}
public void mouseExited(MouseEvent e) {
redispatchMouseEvent(e, false);
}
public void mousePressed(MouseEvent e) {
redispatchMouseEvent(e, false);
}
public void mouseReleased(MouseEvent e) {
redispatchMouseEvent(e, true);
}
//A basic implementation of redispatching events.
private void redispatchMouseEvent(MouseEvent e,
boolean repaint) {
Point glassPanePoint = e.getPoint();
Container container = contentPane;
Point containerPoint = SwingUtilities.convertPoint(
glassPane,
glassPanePoint,
contentPane);
if (containerPoint.y < 0) { //we are not in the content pane
if (containerPoint.y + menuBar.getHeight() >= 0) {
//The mouse event is over the menu bar.
//Could handle specially.
} else {
//The mouse event is over non-system window
//decorations, such as the ones provided by
//the Java look and feel.
//Could handle specially.
}
} else {
//The mouse event is probably over the content pane.
//Find out exactly which component it is over.
Component component = SwingUtilities.getDeepestComponentAt(
container,
containerPoint.x,
containerPoint.y);
if ((component != null)
&& (component.equals(liveButton))) {
//Forward events over the check box.
Point componentPoint = SwingUtilities.convertPoint(
glassPane,
glassPanePoint,
component);
component.dispatchEvent(new MouseEvent(component,
e.getID(),
e.getWhen(),
e.getModifiers(),
componentPoint.x,
componentPoint.y,
e.getClickCount(),
e.isPopupTrigger()));
}
}
//Update the glass pane if requested.
if (repaint) {
glassPane.setPoint(glassPanePoint);
glassPane.repaint();
}
}
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
JFrame frame = new JFrame("GlassPaneDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Start creating and adding components.
JCheckBox changeButton =
new JCheckBox("Glass pane \"visible\"");
changeButton.setSelected(false);
//Set up the content pane, where the "main GUI" lives.
Container contentPane = frame.getContentPane();
contentPane.setLayout(new FlowLayout());
contentPane.add(changeButton);
contentPane.add(new JButton("Button 1"));
contentPane.add(new JButton("Button 2"));
//Set up the menu bar, which appears above the content pane.
JMenuBar menuBar = new JMenuBar();
JMenu menu = new JMenu("Menu");
menu.add(new JMenuItem("Do nothing"));
menuBar.add(menu);
frame.setJMenuBar(menuBar);
//Set up the glass pane, which appears over both menu bar
//and content pane and is an item listener on the change
//button.
myGlassPane = new MyGlassPane(changeButton, menuBar,
frame.getContentPane());
changeButton.addItemListener(myGlassPane);
frame.setGlassPane(myGlassPane);
