马士兵Java课堂笔记-7-键盘事件测试代码

import java.awt.*;import java.awt.event.*;public class Practice {Frame f = new Frame();Button bn = new Button("上");Button bs = new Button("下");Button bw = new Button("左");Button be = new Button("右");TextField tf = new TextField("键盘显示区");public Practice() {f.add(bn,"North");f.add(bs,"South");f.add(bw,"West");f.add(be,"East");f.add(tf,"Center");f.pack();f.setVisible(true);f.addKeyListener(new KeyAdapter() {public void keyPressed(KeyEvent e) {int keyCode = e.getKeyCode();if(keyCode == KeyEvent.VK_UP) {tf.setText("up");}}});f.addWindowListener(new WindowAdapter() {public void windowClosing(WindowEvent e) {System.exit(0);}});f.repaint();}public static void main(String args[]) {new Practice();}}