Java 中 ActionListener , KeyListener 接口冲突

KeyListener需要焦点的, 如果你按了某个按钮之类的(通常会使这个按钮获得焦点), 那他的父组件(例如这个panel)就无法捕获键盘事件了

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JPanel;
import javax.swing.JTextArea;

/**
* @version 1.0.0
*
* this class inherit JDialog
*
* @author clp
*/

@SuppressWarnings("serial")
public class TestListener extends JDialog {

private JPanel centerPanel = null;
private JTextArea textArea = null;
private JButton button = null;

/**
*
* this constructor inherit JDialog
*
* @param owner
* the parent component(usually use JFrame)
*
* @author clp
*/

public TestListener() {
this.setSize(500, 300);
this.setResizable(false);
this.setLocationRelativeTo(null);
this.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);

centerPanel = new JPanel();

button = new JButton("确定");
centerPanel.add(button);

button.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.println("aa");
}
});

button.addKeyListener(new KeyListener() {
@Override
public void keyTyped(KeyEvent e) {
// TODO Auto-generated method stub

}

@Override
public void keyPressed(KeyEvent e) {
// TODO Auto-generated method stub
if (e.getKeyCode() == e.VK_ENTER) {
System.out.println("bb");
}
}

@Override
public void keyReleased(KeyEvent e) {
// TODO Auto-generated method stub

}
});
Container internalPane = this.getContentPane();
internalPane.setLayout(new BorderLayout());
internalPane.add(centerPanel, BorderLayout.CENTER);

this.setContentPane(internalPane);

this.setVisible(true);
}

public static void main(String[] args) {
new TestListener();
}
}
注意焦点就好了。