KeyAdapter类是一个抽象类（适配器）用于接收键盘事件。这个类的所有方法都是空的。这个类是方便类创建监听器对象。

类声明

以下是声明 java.awt.event.KeyAdapter类：

public abstract class KeyAdapter
   extends Object
      implements KeyListener

类构造函数

S.N.	构造函数 & 描述
1	KeyAdapter()

类方法

S.N.	方法 & 描述
1	void keyPressed(KeyEvent e)  Invoked when a key has been pressed.
2	void keyReleased(KeyEvent e)  Invoked when a key has been released.
3	void keyTyped(KeyEvent e)  Invoked when a key has been typed.

方法继承

这个类从以下类继承的方法：

• java.lang.Object

KeyAdapter 例子

选择使用任何编辑器创建以下java程序在 D:/ > SWING > com > yiibai > gui >

SwingAdapterDemo.java

package com.yiibai.gui;

import java.awt.*;
import java.awt.event.*;

public class SwingAdapterDemo {
   private JFrame mainFrame;
   private JLabel headerLabel;
   private JLabel statusLabel;
   private JPanel controlPanel;

   public SwingAdapterDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      SwingAdapterDemo  swingAdapterDemo = new SwingAdapterDemo();        
      swingAdapterDemo.showKeyAdapterDemo();
   }

   private void prepareGUI(){
      mainFrame = new JFrame("Java SWING Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));

      headerLabel = new JLabel("",JLabel.CENTER );
      statusLabel = new JLabel("",JLabel.CENTER);        

      statusLabel.setSize(350,100);
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
	        System.exit(0);
         }        
      });    
      controlPanel = new JPanel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }

   private void showKeyAdapterDemo(){
      headerLabel.setText("Listener in action: KeyAdapter");      

      final JTextField textField = new JTextField(10);

      textField.addKeyListener(new KeyAdapter() {
         public void keyPressed(KeyEvent e) {                
            if(e.getKeyCode() == KeyEvent.VK_ENTER){
               statusLabel.setText("Entered text: " 
               + textField.getText());
            }
         }        
      });
      JButton okButton = new JButton("OK");
      okButton.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
            statusLabel.setText("Entered text: " 
            + textField.getText());                
         }
      });

      controlPanel.add(textField);
      controlPanel.add(okButton);    
      mainFrame.setVisible(true);  
   }
}

编译程序，使用命令提示符。到 D:/ > SWING 然后输出以下命令。

D:SWING>javac comyiibaiguiSwingAdapterDemo.java

如果没有错误出现，这意味着编译成功。使用下面的命令来运行程序。

D:SWING>java com.yiibai.gui.SwingAdapterDemo

验证下面的输出