摘自：http://www.ntu.edu.sg/home/ehchua/programming/java/J4a_GUI.html 主要内容： 1.ActionListener 2.WindowEvent 3.MouseEvent, MouseMotionListener 4.KeyEvent, KeyListener 1.ActionListener import java.awt.*; // Using AWT container and component classes import java.awt.event.*; // Using AWT event classes and listener interfaces // An AWT program inherits from the top-level container java.awt.Frame public class AWTCounter extends Frame implements ActionListener { private Label lblCount; // Declare component Label private TextField tfCount; // Declare component TextField private Button btnCount; // Declare component Button private int count = 0; // Counter's value /** Constructor to setup GUI components and event handling */ public AWTCounter () { setLayout(new FlowLayout()); // "super" Frame sets its layout to FlowLayout, which arranges the components // from left-to-right, and flow to next row from top-to-bottom. lblCount = new Label("Counter"); // construct Label add(lblCount); // "super" Frame adds Label tfCount = new TextField("0", 10); // construct TextField tfCount.setEditable(false); // set to read-only add(tfCount); // "super" Frame adds tfCount btnCount = new Button("Count"); // construct Button add(btnCount); // "super" Frame adds Button btnCount.addActionListener(this); // Clicking Button source fires ActionEvent // btnCount registers this instance as ActionEvent listener setTitle("AWT Counter"); // "super" Frame sets title setSize(250, 100); // "super" Frame sets initial window size // System.out.println(this); // System.out.println(lblCount); // System.out.println(tfCount); // System.out.println(btnCount); setVisible(true); // "super" Frame shows // System.out.println(this); // System.out.println(lblCount); // System.out.println(tfCount); // System.out.println(btnCount); } /** The entry main() method */ public static void main(String[] args) { // Invoke the constructor to setup the GUI, by allocating an instance AWTCounter app = new AWTCounter(); } /** ActionEvent handler - Called back upon button-click. */ @Override public void actionPerformed(ActionEvent evt) { ++count; // increase the counter value // Display the counter value on the TextField tfCount tfCount.setText(count + ""); // convert int to String } } 2.WindowEvent import java.awt.*; // Using AWT containers and components import java.awt.event.*; // Using AWT events and listener interfaces // An AWT GUI program inherits the top-level container java.awt.Frame public class WindowEventDemo extends Frame implements ActionListener, WindowListener { // This class acts as listener for ActionEvent and WindowEvent // Java supports only single inheritance, where a class can extend // one superclass, but can implement multiple interfaces. private TextField tfCount; private Button btnCount; private int count = 0; // Counter's value /** Constructor to setup the UI components and event handling */ public WindowEventDemo() { setLayout(new FlowLayout()); // "super" Frame sets to FlowLayout add(new Label("Counter")); // "super" Frame adds an anonymous Label tfCount = new TextField("0", 10); // Allocate TextField tfCount.setEditable(false); // read-only add(tfCount); // "super" Frame adds tfCount btnCount = new Button("Count"); // Declare and allocate a Button add(btnCount); // "super" Frame adds btnCount btnCount.addActionListener(this); // btnCount fires ActionEvent to its registered ActionEvent listener // btnCount adds "this" object as an ActionEvent listener addWindowListener(this); // "super" Frame fires WindowEvent to its registered WindowEvent listener // "super" Frame adds "this" object as a WindowEvent listener setTitle("WindowEvent Demo"); // "super" Frame sets title setSize(250, 100); // "super" Frame sets initial size setVisible(true); // "super" Frame shows } /** The entry main() method */ public static void main(String[] args) { new WindowEventDemo(); // Let the construct do the job } /** ActionEvent handler */ @Override public void actionPerformed(ActionEvent evt) { ++count; tfCount.setText(count + ""); } /** WindowEvent handlers */ // Called back upon clicking close-window button @Override public void windowClosing(WindowEvent e) { System.exit(0); // Terminate the program } // Not Used, but need to provide an empty body @Override public void windowOpened(WindowEvent e) { } @Override public void windowClosed(WindowEvent e) { } @Override public void windowIconified(WindowEvent e) { } @Override public void windowDeiconified(WindowEvent e) { } @Override public void windowActivated(WindowEvent e) { } @Override public void windowDeactivated(WindowEvent e) { } } 3.MouseEvent, MouseMotionListener import java.awt.*; import java.awt.event.MouseEvent; import java.awt.event.MouseListener; import java.awt.event.MouseMotionListener; // An AWT GUI program inherits from the top-level container java.awt.Frame public class MouseMotionDemo extends Frame implements MouseListener, MouseMotionListener { // This class acts as MouseListener and MouseMotionListener // To display the (x, y) coordinates of the mouse-clicked private TextField tfMouseClickX; private TextField tfMouseClickY; // To display the (x, y) coordinates of the current mouse-pointer position private TextField tfMousePositionX; private TextField tfMousePositionY; /** Constructor to setup the GUI */ public MouseMotionDemo() { setLayout(new FlowLayout()); // "this" frame sets to FlowLayout add(new Label("X-Click: ")); tfMouseClickX = new TextField(10); tfMouseClickX.setEditable(false); add(tfMouseClickX); add(new Label("Y-Click: ")); tfMouseClickY = new TextField(10); tfMouseClickY.setEditable(false); add(tfMouseClickY); add(new Label("X-Position: ")); tfMousePositionX = new TextField(10); tfMousePositionX.setEditable(false); add(tfMousePositionX); add(new Label("Y-Position: ")); tfMousePositionY = new TextField(10); tfMousePositionY.setEditable(false); add(tfMousePositionY); addMouseListener(this); addMouseMotionListener(this); // "super" frame fires MouseEvent to all its registered MouseListener and MouseMotionListener // "super" frame adds "this" object as MouseListener and MouseMotionListener setTitle("MouseMotion Demo"); // "super" Frame sets title setSize(400, 120); // "super" Frame sets initial size setVisible(true); // "super" Frame shows } /** The entry main() method */ public static void main(String[] args) { new MouseMotionDemo(); // Let the constructor do the job } /** MouseListener handlers */ // Called back when a mouse-button has been clicked @Override public void mouseClicked(MouseEvent e) { tfMouseClickX.setText(e.getX() + ""); tfMouseClickY.setText(e.getY() + ""); } // Not Used, but need to provide an empty body for compilation @Override public void mousePressed(MouseEvent e) { } @Override public void mouseReleased(MouseEvent e) { } @Override public void mouseEntered(MouseEvent e) { } @Override public void mouseExited(MouseEvent e) { } /** MouseMotionEvent handlers */ // Called back when the mouse-pointer has been moved @Override public void mouseMoved(MouseEvent e) { tfMousePositionX.setText(e.getX() + ""); tfMousePositionY.setText(e.getY() + ""); } // Not Used, but need to provide an empty body for compilation @Override public void mouseDragged(MouseEvent e) { } } 4.KeyEvent, KeyListener import java.awt.*; import java.awt.event.KeyEvent; import java.awt.event.KeyListener; // An AWT GUI program inherits from the top-level container java.awt.Frame public class KeyEventDemo extends Frame implements KeyListener { // This class acts as KeyEvent Listener private TextField tfInput; // single-line TextField to receive tfInput key private TextArea taDisplay; // multi-line TextArea to taDisplay result /** Constructor to setup the GUI */ public KeyEventDemo() { setLayout(new FlowLayout()); // "super" frame sets to FlowLayout add(new Label("Enter Text: ")); tfInput = new TextField(10); add(tfInput); taDisplay = new TextArea(5, 40); // 5 rows, 40 columns add(taDisplay); tfInput.addKeyListener(this); // tfInput TextField fires KeyEvent to its registered KeyListeners // tfInput adds "this" object as a KeyEvent listener setTitle("KeyEvent Demo"); // "super" Frame sets title setSize(400, 200); // "super" Frame sets initial size setVisible(true); // "super" Frame shows } /** The entry main() method */ public static void main(String[] args) { new KeyEventDemo(); // Let the constructor do the job } /** KeyEvent handlers */ // Called back when a key has been typed (pressed and released) @Override public void keyTyped(KeyEvent e) { taDisplay.append("You have typed " + e.getKeyChar() + " "); } // Not Used, but need to provide an empty body for compilation @Override public void keyPressed(KeyEvent e) { } @Override public void keyReleased(KeyEvent e) { } }