【求一个简单事件例子】(马上给分)

Question

JTextField txt = new JTextField();
txt.addFocusListener(new FocusListener()
{
   public void focusGained(FocusEvent e)
   {
     System.out.println("gained");
   }
   public void focusLost(FocusEvent e)
   {
     System.out.println("lost");
    }}
看看JDK文档关于FocusListener的说明
);

Answer 1

import javax.swing.*;import java.awt.*;
import java.awt.event.*;class NMailLoginWin extends JFrame{
  private JPanel contentPane;
  private FlowLayout flowLayout1 = new FlowLayout();  private JTextField jUserField=new JTextField();
  public NMailLoginWin(){
    //super("", false, false, false, false);
    enableEvents(AWTEvent.WINDOW_EVENT_MASK);    try {
      winInit();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }  private void winInit(){
    contentPane=(JPanel)this.getContentPane();
    contentPane.setLayout(flowLayout1);    this.setSize(new Dimension(200, 150));
    this.setLocation(100,20);
    this.setTitle("NMail");    jUserField.setMaximumSize(new Dimension(100, 22));
    jUserField.setPreferredSize(new Dimension(100, 22));
    contentPane.add(jUserField,null);    jUserField.addMouseListener(new MouseAdapter(){
      public void mouseEntered(MouseEvent e){
        jUserField.setText("get");
      }
      public void mouseExited(MouseEvent e){
        jUserField.setText("lost");
      }
    });
  }  public static void main(String[] a){
    new NMailLoginWin().show();
  }
}

Answer 2

谢谢  Abib(挽留刀)
to  fpwang(胖子) 您理解错意思了！