Java/Swing JFC/Various Event Listener

Содержание

1 Demonstrating the ActionListener
2 Demonstrating the AdjustmentListener
3 Demonstrating the AncestorListener
4 Demonstrating the ComponentListener
5 Demonstrating the ContainerListener
6 Demonstrating the FocusListener
7 Demonstrating the HyperlinkListener
8 Demonstrating the InternalFrameListener
9 Demonstrating the ItemListener
10 Demonstrating the KeyListener
11 Demonstrating the MenuListener
12 Demonstrating the MouseListener and MouseMotionListener
13 Demonstrating the MouseWheelListener
14 Demonstrating the PopupMenuListener
15 Demonstrating the WindowListener
16 Demonstrating the WindowListener with a WindowAdapter
17 Responding to Keystrokes

Demonstrating the ActionListener

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Container; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.KeyEvent; import javax.swing.JButton; import javax.swing.JComboBox; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JTextField; public class ActionTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame();
   Container contentPane = frame.getContentPane();
   ActionListener listener = new ActionListener() {
     public void actionPerformed(ActionEvent e) {
       System.out.println("Command: " + e.getActionCommand());
       System.out.println("Modifiers: ");
       int modifiers = e.getModifiers();
       System.out.println("\tALT : "
           + checkMod(modifiers, ActionEvent.ALT_MASK));
       System.out.println("\tCTRL : "
           + checkMod(modifiers, ActionEvent.CTRL_MASK));
       System.out.println("\tMETA : "
           + checkMod(modifiers, ActionEvent.META_MASK));
       System.out.println("\tSHIFT: "
           + checkMod(modifiers, ActionEvent.SHIFT_MASK));
       Object source = e.getSource();
       if (source instanceof JComboBox) {
         JComboBox jb = (JComboBox) source;
         System.out.println("Combo: " + jb.getSelectedItem());
       }
     }
     private boolean checkMod(int modifiers, int mask) {
       return ((modifiers & mask) == mask);
     }
   };
   String flavors[] = { "Item 1", "Item 2", "Item 3"};
   JComboBox jc = new JComboBox(flavors);
   jc.setMaximumRowCount(4);
   jc.setEditable(true);
   jc.addActionListener(listener);
   contentPane.add(jc, BorderLayout.NORTH);
   JButton b = new JButton("Button!");
   b.addActionListener(listener);
   contentPane.add(b, BorderLayout.CENTER);
   JPanel panel = new JPanel();
   JLabel label = new JLabel("Label 1: ");
   JTextField text = new JTextField("Type your text", 15);
   text.addActionListener(listener);
   label.setDisplayedMnemonic(KeyEvent.VK_1);
   label.setLabelFor(text);
   panel.add(label);
   panel.add(text);
   contentPane.add(panel, BorderLayout.SOUTH);
   frame.pack();
   frame.show();
 }

}

      </source>

Demonstrating the AdjustmentListener

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Container; import java.awt.event.AdjustmentEvent; import java.awt.event.AdjustmentListener; import javax.swing.Icon; import javax.swing.ImageIcon; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JScrollBar; import javax.swing.JScrollPane; public class AdjustmentTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame();
   Container contentPane = frame.getContentPane();
   Icon icon = new ImageIcon("jexp.gif");
   JButton b = new JButton(icon);
   JScrollPane pane = new JScrollPane(b);
   AdjustmentListener hListener = new AdjustmentListener() {
     public void adjustmentValueChanged(AdjustmentEvent e) {
       System.out.println("Horizontal: ");
       dumpInfo(e);
     }
   };
   JScrollBar hBar = pane.getHorizontalScrollBar();
   hBar.addAdjustmentListener(hListener);
   AdjustmentListener vListener = new AdjustmentListener() {
     public void adjustmentValueChanged(AdjustmentEvent e) {
       System.out.println("Vertical: ");
       dumpInfo(e);
     }
   };
   JScrollBar vBar = pane.getVerticalScrollBar();
   vBar.addAdjustmentListener(vListener);
   contentPane.add(pane, BorderLayout.CENTER);
   frame.setSize(300, 200);
   frame.show();
 }
 private static void dumpInfo(AdjustmentEvent e) {
   System.out.println("\tValue: " + e.getValue());
   String type = null;
   switch (e.getAdjustmentType()) {
   case AdjustmentEvent.TRACK:
     type = "Track";
     break;
   case AdjustmentEvent.BLOCK_DECREMENT:
     type = "Block Decrement";
     break;
   case AdjustmentEvent.BLOCK_INCREMENT:
     type = "Block Increment";
     break;
   case AdjustmentEvent.UNIT_DECREMENT:
     type = "Unit Decrement";
     break;
   case AdjustmentEvent.UNIT_INCREMENT:
     type = "Unit Increment";
     break;
   }
   System.out.println("\tType: " + type);
 }

}

      </source>

Demonstrating the AncestorListener

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Container; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.util.Timer; import java.util.TimerTask; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.event.AncestorEvent; import javax.swing.event.AncestorListener; public class AncestorTest {

 public static void main(String args[]) {
   final JFrame frame = new JFrame();
   Container contentPane = frame.getContentPane();
   JButton b = new JButton("Hide for 5");
   ActionListener action = new ActionListener() {
     public void actionPerformed(ActionEvent actionEvent) {
       frame.setVisible(false);
       TimerTask task = new TimerTask() {
         public void run() {
           frame.setVisible(true);
         }
       };
       Timer timer = new Timer();
       timer.schedule(task, 5000);
     }
   };
   b.addActionListener(action);
   AncestorListener ancestor = new AncestorListener() {
     public void ancestorAdded(AncestorEvent e) {
       System.out.println("Added");
       dumpInfo(e);
     }
     public void ancestorMoved(AncestorEvent e) {
       System.out.println("Moved");
       dumpInfo(e);
     }
     public void ancestorRemoved(AncestorEvent e) {
       System.out.println("Removed");
       dumpInfo(e);
     }
     private void dumpInfo(AncestorEvent e) {
       System.out.println("\tAncestor: " + name(e.getAncestor()));
       System.out.println("\tAncestorParent: "
           + name(e.getAncestorParent()));
       System.out.println("\tComponent: " + name(e.getComponent()));
     }
     private String name(Container c) {
       return (c == null) ? null : c.getName();
     }
   };
   b.addAncestorListener(ancestor);
   contentPane.add(b, BorderLayout.NORTH);
   frame.setSize(300, 200);
   frame.show();
 }

}

      </source>

Demonstrating the ComponentListener

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Container; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.ruponentEvent; import java.awt.event.ruponentListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JSplitPane; public class SwingComponentTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame();
   Container contentPane = frame.getContentPane();
   ComponentListener comp = new ComponentListener() {
     public void componentHidden(ComponentEvent e) {
       dump("Hidden", e);
     }
     public void componentMoved(ComponentEvent e) {
       dump("Moved", e);
     }
     public void componentResized(ComponentEvent e) {
       dump("Resized", e);
     }
     public void componentShown(ComponentEvent e) {
       dump("Shown", e);
     }
     private void dump(String type, ComponentEvent e) {
       System.out.println(e.getComponent().getName() + " : " + type);
     }
   };
   JButton left = new JButton("Left");
   left.setName("Left");
   left.addComponentListener(comp);
   final JButton right = new JButton("Right");
   right.setName("Right");
   right.addComponentListener(comp);
   ActionListener action = new ActionListener() {
     public void actionPerformed(ActionEvent e) {
       right.setVisible(!right.isVisible());
     }
   };
   left.addActionListener(action);
   JSplitPane pane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, true,
       left, right);
   contentPane.add(pane, BorderLayout.CENTER);
   frame.setSize(300, 200);
   frame.show();
 }

}

      </source>

Demonstrating the ContainerListener

   <source lang="java">

import java.awt.ruponent; import java.awt.Container; import java.awt.GridLayout; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.ContainerEvent; import java.awt.event.ContainerListener; import javax.swing.JButton; import javax.swing.JFrame; public class ContainerTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame();
   Container contentPane = frame.getContentPane();
   ContainerListener cont = new ContainerListener() {
     ActionListener listener = new ActionListener() {
       public void actionPerformed(ActionEvent e) {
         System.out.println("Selected: " + e.getActionCommand());
       }
     };
     public void componentAdded(ContainerEvent e) {
       Component c = e.getChild();
       if (c instanceof JButton) {
         JButton b = (JButton) c;
         b.addActionListener(listener);
       }
     }
     public void componentRemoved(ContainerEvent e) {
       Component c = e.getChild();
       if (c instanceof JButton) {
         JButton b = (JButton) c;
         b.removeActionListener(listener);
       }
     }
   };
   contentPane.addContainerListener(cont);
   contentPane.setLayout(new GridLayout(3, 2));
   contentPane.add(new JButton("First"));
   contentPane.add(new JButton("Second"));
   contentPane.add(new JButton("Third"));
   contentPane.add(new JButton("Fourth"));
   contentPane.add(new JButton("Fifth"));
   frame.setSize(300, 200);
   frame.show();
 }

}

      </source>

Demonstrating the FocusListener

   <source lang="java">

import java.awt.BorderLayout; import java.awt.ruponent; import java.awt.Container; import java.awt.event.FocusEvent; import java.awt.event.FocusListener; import java.awt.event.KeyEvent; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; import javax.swing.JTextField; public class FocusTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame();
   Container contentPane = frame.getContentPane();
   FocusListener listener = new FocusListener() {
     public void focusGained(FocusEvent e) {
       dumpInfo(e);
     }
     public void focusLost(FocusEvent e) {
       dumpInfo(e);
     }
     private void dumpInfo(FocusEvent e) {
       System.out.println("Source  : " + name(e.getComponent()));
       System.out.println("Opposite : "
           + name(e.getOppositeComponent()));
       System.out.println("Temporary: " + e.isTemporary());
     }
     private String name(Component c) {
       return (c == null) ? null : c.getName();
     }
   };
   // First
   JPanel panel = new JPanel();
   JLabel label = new JLabel("Label 1: ");
   JTextField text = new JTextField("Type your text", 15);
   text.setName("First");
   text.addFocusListener(listener);
   label.setDisplayedMnemonic(KeyEvent.VK_1);
   label.setLabelFor(text);
   panel.add(label);
   panel.add(text);
   contentPane.add(panel, BorderLayout.NORTH);
   // Second
   panel = new JPanel();
   label = new JLabel("Label 2: ");
   text = new JTextField("14.0", 10);
   text.setName("Second");
   text.addFocusListener(listener);
   text.setHorizontalAlignment(JTextField.RIGHT);
   label.setDisplayedMnemonic(KeyEvent.VK_2);
   label.setLabelFor(text);
   panel.add(label);
   panel.add(text);
   contentPane.add(panel, BorderLayout.SOUTH);
   frame.pack();
   frame.show();
 }

}

      </source>

Demonstrating the HyperlinkListener

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Container; import java.io.IOException; import javax.swing.JEditorPane; import javax.swing.JFrame; import javax.swing.JScrollPane; import javax.swing.event.HyperlinkEvent; import javax.swing.event.HyperlinkListener; public class HyperlinkTest {

 public static void main(String args[]) {
     JFrame frame = new JFrame();
   Container contentPane = frame.getContentPane();
   final JEditorPane ep = new JEditorPane();
   try {
     ep.setPage("http://www.jexp.ru");
   } catch (IOException e) {
     System.err.println("Bad URL: " + e);
     System.exit(-1);
   }
   HyperlinkListener listener = new HyperlinkListener() {
     public void hyperlinkUpdate(HyperlinkEvent e) {
       if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED) {
         try {
           ep.setPage(e.getURL());
         } catch (IOException ioe) {
           System.err.println("Error loading: " + ioe);
         }
       }
     }
   };
   ep.addHyperlinkListener(listener);
   ep.setEditable(false);
   JScrollPane pane = new JScrollPane(ep);
   contentPane.add(pane, BorderLayout.CENTER);
   frame.setSize(640, 480);
   frame.show();
 }

}

      </source>

Demonstrating the InternalFrameListener

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Container; import javax.swing.JDesktopPane; import javax.swing.JFrame; import javax.swing.JInternalFrame; import javax.swing.JLabel; import javax.swing.JLayeredPane; import javax.swing.event.InternalFrameEvent; import javax.swing.event.InternalFrameListener; public class InternalFrameTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Internal Frame Listener");
   Container contentPane = frame.getContentPane();
   JLayeredPane desktop = new JDesktopPane();
   desktop.setOpaque(false);
   desktop.add(createLayer("One"), JLayeredPane.POPUP_LAYER);
   desktop.add(createLayer("Two"), JLayeredPane.DEFAULT_LAYER);
   desktop.add(createLayer("Three"), JLayeredPane.PALETTE_LAYER);
   contentPane.add(desktop, BorderLayout.CENTER);
   frame.setSize(300, 300);
   frame.show();
 }
 static JInternalFrame createLayer(String label) {
   return new SelfInternalFrame(label);
 }
 static class SelfInternalFrame extends JInternalFrame {
   InternalFrameListener listener = new InternalFrameListener() {
     public void internalFrameActivated(InternalFrameEvent e) {
       dumpInfo("Activated", e);
     }
     public void internalFrameClosed(InternalFrameEvent e) {
       dumpInfo("Closed", e);
     }
     public void internalFrameClosing(InternalFrameEvent e) {
       dumpInfo("Closing", e);
     }
     public void internalFrameDeactivated(InternalFrameEvent e) {
       dumpInfo("Deactivated", e);
     }
     public void internalFrameDeiconified(InternalFrameEvent e) {
       dumpInfo("Deiconified", e);
     }
     public void internalFrameIconified(InternalFrameEvent e) {
       dumpInfo("Iconified", e);
     }
     public void internalFrameOpened(InternalFrameEvent e) {
       dumpInfo("Opened", e);
     }
     private void dumpInfo(String s, InternalFrameEvent e) {
       System.out.println("Source: " + e.getInternalFrame().getName()
           + " : " + s);
     }
   };
   public SelfInternalFrame(String s) {
     getContentPane().add(new JLabel(s, JLabel.CENTER),
         BorderLayout.CENTER);
     setName(s);
     addInternalFrameListener(listener);
     setBounds(50, 50, 100, 100);
     setResizable(true);
     setClosable(true);
     setMaximizable(true);
     setIconifiable(true);
     setTitle(s);
     setVisible(true);
   }
 }

}

      </source>

Demonstrating the ItemListener

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Container; import java.awt.GridLayout; import java.awt.event.ItemEvent; import java.awt.event.ItemListener; import javax.swing.ButtonGroup; import javax.swing.JComboBox; import javax.swing.JComponent; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JRadioButton; public class ItemTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame();
   Container contentPane = frame.getContentPane();
   ItemListener listener = new ItemListener() {
     public void itemStateChanged(ItemEvent e) {
       System.out.println("Source: " + name(e.getSource()));
       System.out.println("Item: " + name(e.getItem()));
       int state = e.getStateChange();
       System.out.println("State: "
           + ((state == ItemEvent.SELECTED) ? "Selected"
               : "Deselected"));
     }
     private String name(Object o) {
       if (o instanceof JComponent) {
         JComponent comp = (JComponent) o;
         return comp.getName();
       } else {
         return o.toString();
       }
     }
   };
   JPanel panel = new JPanel(new GridLayout(0, 1));
   ButtonGroup group = new ButtonGroup();
   JRadioButton option = new JRadioButton("French Fries", true);
   option.setName(option.getText());
   option.addItemListener(listener);
   group.add(option);
   panel.add(option);
   option = new JRadioButton("Onion Rings", false);
   option.setName(option.getText());
   option.addItemListener(listener);
   group.add(option);
   panel.add(option);
   option = new JRadioButton("Ice Cream", false);
   option.setName(option.getText());
   option.addItemListener(listener);
   group.add(option);
   panel.add(option);
   contentPane.add(panel, BorderLayout.NORTH);
   String flavors[] = { "Item 1", "Item 2", "Item 3"};
   JComboBox jc = new JComboBox(flavors);
   jc.setName("Combo");
   jc.addItemListener(listener);
   jc.setMaximumRowCount(4);
   contentPane.add(jc, BorderLayout.SOUTH);
   frame.pack();
   frame.show();
 }

}

      </source>

Demonstrating the KeyListener

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Container; import java.awt.event.KeyEvent; import java.awt.event.KeyListener; import javax.swing.JFrame; import javax.swing.JTextField; public class KeyTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Key Listener");
   Container contentPane = frame.getContentPane();
   KeyListener listener = new KeyListener() {
     public void keyPressed(KeyEvent e) {
       dumpInfo("Pressed", e);
     }
     public void keyReleased(KeyEvent e) {
       dumpInfo("Released", e);
     }
     public void keyTyped(KeyEvent e) {
       dumpInfo("Typed", e);
     }
     private void dumpInfo(String s, KeyEvent e) {
       System.out.println(s);
       int code = e.getKeyCode();
       System.out.println("\tCode: " + KeyEvent.getKeyText(code));
       System.out.println("\tChar: " + e.getKeyChar());
       int mods = e.getModifiersEx();
       System.out.println("\tMods: "
           + KeyEvent.getModifiersExText(mods));
       System.out.println("\tLocation: "
           + location(e.getKeyLocation()));
       System.out.println("\tAction? " + e.isActionKey());
     }
     private String location(int location) {
       switch (location) {
       case KeyEvent.KEY_LOCATION_LEFT:
         return "Left";
       case KeyEvent.KEY_LOCATION_RIGHT:
         return "Right";
       case KeyEvent.KEY_LOCATION_NUMPAD:
         return "NumPad";
       case KeyEvent.KEY_LOCATION_STANDARD:
         return "Standard";
       case KeyEvent.KEY_LOCATION_UNKNOWN:
       default:
         return "Unknown";
       }
     }
   };
   JTextField text = new JTextField();
   text.addKeyListener(listener);
   contentPane.add(text, BorderLayout.NORTH);
   frame.pack();
   frame.show();
 }

}

      </source>

Demonstrating the MenuListener

   <source lang="java">

import javax.swing.ButtonGroup; import javax.swing.JCheckBoxMenuItem; import javax.swing.JFrame; import javax.swing.JMenu; import javax.swing.JMenuBar; import javax.swing.JMenuItem; import javax.swing.JRadioButtonMenuItem; import javax.swing.event.MenuEvent; import javax.swing.event.MenuListener; public class MenuTest extends JFrame {

 public MenuTest() {
   super();
   MenuListener listener = new MenuListener() {
     public void menuCanceled(MenuEvent e) {
       dumpInfo("Canceled", e);
     }
     public void menuDeselected(MenuEvent e) {
       dumpInfo("Deselected", e);
     }
     public void menuSelected(MenuEvent e) {
       dumpInfo("Selected", e);
     }
     private void dumpInfo(String s, MenuEvent e) {
       JMenu menu = (JMenu) e.getSource();
       System.out.println(s + ": " + menu.getText());
     }
   };
   JMenu fileMenu = new JMenu("File");
   fileMenu.addMenuListener(listener);
   fileMenu.add(new JMenuItem("Open"));
   fileMenu.add(new JMenuItem("Close"));
   fileMenu.add(new JMenuItem("Exit"));
   JMenu helpMenu = new JMenu("Help");
   helpMenu.addMenuListener(listener);
   helpMenu.add(new JMenuItem("About MenuTest"));
   helpMenu.add(new JMenuItem("Class Hierarchy"));
   helpMenu.addSeparator();
   helpMenu.add(new JCheckBoxMenuItem("Balloon Help"));
   JMenu subMenu = new JMenu("Categories");
   subMenu.addMenuListener(listener);
   JRadioButtonMenuItem rb;
   ButtonGroup group = new ButtonGroup();
   subMenu.add(rb = new JRadioButtonMenuItem("A Little Help", true));
   group.add(rb);
   subMenu.add(rb = new JRadioButtonMenuItem("A Lot of Help"));
   group.add(rb);
   helpMenu.add(subMenu);
   JMenuBar mb = new JMenuBar();
   mb.add(fileMenu);
   mb.add(helpMenu);
   setJMenuBar(mb);
 }
 public static void main(String args[]) {
   JFrame frame = new MenuTest();
   frame.setSize(300, 300);
   frame.show();
 }

}

      </source>

Demonstrating the MouseListener and MouseMotionListener

   <source lang="java">

import java.awt.Color; import java.awt.Graphics; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.awt.event.MouseMotionListener; import javax.swing.JFrame; import javax.swing.JMenuItem; import javax.swing.JPopupMenu; public class MouseTest extends JFrame {

 int startX, startY, endX, endY;
 Color color = Color.BLACK;
 public MouseTest() {
   super();
   final JPopupMenu pop = new JPopupMenu();
   pop.add(new JMenuItem("Cut"));
   pop.add(new JMenuItem("Copy"));
   pop.add(new JMenuItem("Paste"));
   pop.addSeparator();
   pop.add(new JMenuItem("Select All"));
   pop.setInvoker(this);
   MouseListener popup = new MouseListener() {
     public void mouseClicked(MouseEvent e) {
     }
     public void mouseEntered(MouseEvent e) {
     }
     public void mouseExited(MouseEvent e) {
     }
     public void mousePressed(MouseEvent e) {
       if (e.isPopupTrigger()) {
         showPopup(e);
       }
     }
     public void mouseReleased(MouseEvent e) {
       if (e.isPopupTrigger()) {
         showPopup(e);
       }
     }
     private void showPopup(MouseEvent e) {
       pop.show(e.getComponent(), e.getX(), e.getY());
     }
   };
   addMouseListener(popup);
   MouseListener drawing1 = new MouseListener() {
     public void mouseClicked(MouseEvent e) {
     }
     public void mouseEntered(MouseEvent e) {
     }
     public void mouseExited(MouseEvent e) {
     }
     public void mousePressed(MouseEvent e) {
       color = Color.RED;
       startX = endX = e.getX();
       startY = endY = e.getY();
       repaint();
     }
     public void mouseReleased(MouseEvent e) {
       color = Color.BLACK;
       repaint();
     }
   };
   addMouseListener(drawing1);
   MouseMotionListener drawing2 = new MouseMotionListener() {
     public void mouseDragged(MouseEvent e) {
       endX = e.getX();
       endY = e.getY();
       repaint();
     }
     public void mouseMoved(MouseEvent e) {
     }
   };
   addMouseMotionListener(drawing2);
 }
 public void paint(Graphics g) {
   super.paint(g);
   g.setColor(color);
   g.drawLine(startX, startY, endX, endY);
 }
 public static void main(String args[]) {
   JFrame frame = new MouseTest();
   frame.setSize(300, 300);
   frame.show();
 }

}

      </source>

Demonstrating the MouseWheelListener

   <source lang="java">

import java.awt.Color; import java.awt.Container; import java.awt.event.MouseWheelEvent; import java.awt.event.MouseWheelListener; import javax.swing.JFrame; public class MouseWheelTest extends JFrame {

 private static final Color colors[] = { Color.BLACK, Color.BLUE,
     Color.CYAN, Color.DARK_GRAY, Color.GRAY, Color.GREEN,
     Color.LIGHT_GRAY, Color.MAGENTA, Color.ORANGE, Color.PINK,
     Color.RED, Color.WHITE, Color.YELLOW };
 public MouseWheelTest() {
   super();
   final Container contentPane = getContentPane();
   MouseWheelListener listener = new MouseWheelListener() {
     int colorCounter;
     private static final int UP = 1;
     private static final int DOWN = 2;
     public void mouseWheelMoved(MouseWheelEvent e) {
       int count = e.getWheelRotation();
       int direction = (Math.abs(count) > 0) ? UP : DOWN;
       changeBackground(direction);
     }
     private void changeBackground(int direction) {
       contentPane.setBackground(colors[colorCounter]);
       if (direction == UP) {
         colorCounter++;
       } else {
         --colorCounter;
       }
       if (colorCounter == colors.length) {
         colorCounter = 0;
       } else if (colorCounter < 0) {
         colorCounter = colors.length - 1;
       }
     }
   };
   contentPane.addMouseWheelListener(listener);
 }
 public static void main(String args[]) {
   JFrame frame = new MouseWheelTest();
   frame.setSize(300, 300);
   frame.show();
 }

}

      </source>

Demonstrating the PopupMenuListener

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Container; import javax.swing.ruboBoxModel; import javax.swing.DefaultComboBoxModel; import javax.swing.JComboBox; import javax.swing.JFrame; import javax.swing.event.PopupMenuEvent; import javax.swing.event.PopupMenuListener; public class PopupTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Popup Menu Listener");
   Container contentPane = frame.getContentPane();
   final String flavors[] = { "Item 1", "Item 2", "Item 3"};
   PopupMenuListener listener = new PopupMenuListener() {
     boolean initialized = false;
     public void popupMenuCanceled(PopupMenuEvent e) {
     }
     public void popupMenuWillBecomeInvisible(PopupMenuEvent e) {
     }
     public void popupMenuWillBecomeVisible(PopupMenuEvent e) {
       if (!initialized) {
         JComboBox combo = (JComboBox) e.getSource();
         ComboBoxModel model = new DefaultComboBoxModel(flavors);
         combo.setModel(model);
         initialized = true;
       }
     }
   };
   JComboBox jc = new JComboBox();
   jc.addPopupMenuListener(listener);
   jc.setMaximumRowCount(4);
   jc.setEditable(true);
   contentPane.add(jc, BorderLayout.NORTH);
   frame.pack();
   frame.show();
 }

}

      </source>

Demonstrating the WindowListener

   <source lang="java">

import java.awt.event.WindowEvent; import java.awt.event.WindowListener; import javax.swing.JFrame; public class WindowTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Window Listener");
   WindowListener listener = new WindowListener() {
     public void windowActivated(WindowEvent w) {
       System.out.println(w);
     }
     public void windowClosed(WindowEvent w) {
       System.out.println(w);
     }
     public void windowClosing(WindowEvent w) {
       System.out.println(w);
       System.exit(0);
     }
     public void windowDeactivated(WindowEvent w) {
       System.out.println(w);
     }
     public void windowDeiconified(WindowEvent w) {
       System.out.println(w);
     }
     public void windowIconified(WindowEvent w) {
       System.out.println(w);
     }
     public void windowOpened(WindowEvent w) {
       System.out.println(w);
     }
   };
   frame.addWindowListener(listener);
   frame.setSize(300, 300);
   frame.show();
 }

}

      </source>

Demonstrating the WindowListener with a WindowAdapter

   <source lang="java">

import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import java.awt.event.WindowListener; import javax.swing.JFrame; public class WindowAdapterTest {

 public static void main(String args[]) {
   JFrame frame = new JFrame("Window Listener");
   WindowListener listener = new WindowAdapter() {
     public void windowClosing(WindowEvent w) {
       System.exit(0);
     }
   };
   frame.addWindowListener(listener);
   frame.setSize(300, 300);
   frame.show();
 }

}

      </source>

Responding to Keystrokes

   <source lang="java">

import java.awt.BorderLayout; import java.awt.Container; import java.awt.event.ActionEvent; import javax.swing.AbstractAction; import javax.swing.Action; import javax.swing.ActionMap; import javax.swing.InputMap; import javax.swing.JButton; import javax.swing.JComponent; import javax.swing.JFrame; import javax.swing.KeyStroke; public class KeyTester {

 static class MyActionListener extends AbstractAction {
   MyActionListener(String s) {
     super(s);
   }
   public void actionPerformed(ActionEvent e) {
     System.out.println(getValue(Action.NAME));
   }
 }
 public static void main(String args[]) {
   String actionKey = "theAction";
   JFrame f = new JFrame("Key Tester");

JButton jb1 = new JButton("<html>B
Focused/Typed");

   JButton jb2 = new JButton("<html><center>Ctrl-C
Window/Pressed");
   JButton jb3 = new JButton("<html><center>Shift-D
Ancestor/Released");
   Container pane = f.getContentPane();
   pane.add(jb1, BorderLayout.NORTH);
   pane.add(jb2, BorderLayout.CENTER);
   pane.add(jb3, BorderLayout.SOUTH);
   KeyStroke stroke = KeyStroke.getKeyStroke("typed B");
   Action action = new MyActionListener("Action Happened");
   // Defaults to JComponent.WHEN_FOCUSED map
   InputMap inputMap = jb1.getInputMap();
   inputMap.put(stroke, actionKey);
   ActionMap actionMap = jb1.getActionMap();
   actionMap.put(actionKey, action);
   stroke = KeyStroke.getKeyStroke("ctrl C");
   action = new MyActionListener("Action Didn"t Happen");
   inputMap = jb2.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW);
   inputMap.put(stroke, actionKey);
   actionMap = jb2.getActionMap();
   actionMap.put(actionKey, action);
   stroke = KeyStroke.getKeyStroke("shift released D");
   action = new MyActionListener("What Happened?");
   inputMap = jb3
       .getInputMap(JComponent.WHEN_ANCESTOR_OF_FOCUSED_COMPONENT);
   inputMap.put(stroke, actionKey);
   actionMap = jb3.getActionMap();
   actionMap.put(actionKey, action);
   f.setSize(200, 200);
   f.show();
 }

}

      </source>