import javax.swing.*; import javax.swing.event.MouseInputAdapter; import java.awt.*; import java.awt.event.*; public class GlassPaneDemo extends JApplet{ static private MyGlassPane myGlassPane; public static void main(String[] args) { JFrame frame = new JFrame("GlassPaneDemo"); frame.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }); JCheckBox changeButton = new JCheckBox("Glass pane \"visible\""); changeButton.setSelected(false); changeButton.addItemListener(new ItemListener() { public void itemStateChanged(ItemEvent e) { myGlassPane.setVisible(e.getStateChange() == ItemEvent.SELECTED); } }); //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. myGlassPane = new MyGlassPane(changeButton, menuBar, frame.getContentPane()); frame.setGlassPane(myGlassPane); frame.pack(); frame.setVisible(true); } public void init(){ JCheckBox changeButton = new JCheckBox("Glass pane \"visible\""); changeButton.setSelected(false); changeButton.addItemListener(new ItemListener() { public void itemStateChanged(ItemEvent e) { myGlassPane.setVisible(e.getStateChange() == ItemEvent.SELECTED); } }); //Set up the content pane, where the "main GUI" lives. Container contentPane = 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); setJMenuBar(menuBar); //Set up the glass pane, which appears over both menu bar //and content pane. myGlassPane = new MyGlassPane(changeButton, menuBar, getContentPane()); setGlassPane(myGlassPane); } } /** * We have to provide our own glass pane so that it can paint. */ class MyGlassPane extends JComponent { Point point; public void paint(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; boolean inDrag = false; 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); } /* * We must forward at least the mouse drags that started * with mouse presses over the check box. Otherwise, * when the user presses the check box then drags off, * the check box isn't disarmed -- it keeps its dark * gray background or whatever its L&F uses to indicate * that the button is currently being pressed. */ 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); inDrag = false; } private void redispatchMouseEvent(MouseEvent e, boolean repaint) { boolean inButton = false; boolean inMenuBar = false; Point glassPanePoint = e.getPoint(); Component component = null; Container container = contentPane; Point containerPoint = SwingUtilities.convertPoint( glassPane, glassPanePoint, contentPane); int eventID = e.getID(); if (containerPoint.y < 0) { inMenuBar = true; container = menuBar; containerPoint = SwingUtilities.convertPoint( glassPane, glassPanePoint, menuBar); testForDrag(eventID); } //XXX: If the event is from a component in a popped-up menu, //XXX: then the container should probably be the menu's //XXX: JPopupMenu, and containerPoint should be adjusted //XXX: accordingly. component = SwingUtilities.getDeepestComponentAt( container, containerPoint.x, containerPoint.y); if (component == null) { return; } if (component.equals(liveButton)) { inButton = true; testForDrag(eventID); } if (inMenuBar || inButton || inDrag) { Point componentPoint = SwingUtilities.convertPoint( glassPane, glassPanePoint, component); component.dispatchEvent(new MouseEvent(component, eventID, e.getWhen(), e.getModifiers(), componentPoint.x, componentPoint.y, e.getClickCount(), e.isPopupTrigger())); } if (repaint) { toolkit.beep(); glassPane.setPoint(glassPanePoint); glassPane.repaint(); } } private void testForDrag(int eventID) { if (eventID == MouseEvent.MOUSE_PRESSED) { inDrag = true; } } }