谁能给我一个弹出式菜单的小例子。。。在线等

Question

java how to progroamming上有

Answer 1

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;public class PopupMenuextends JFrame
{
public PopupMenu(String strTitle)
{
super(strTitle);
final JPopupMenu mnu=new JPopupMenu();
mnu.add(new JMenuItem("new"));
mnu.add(new JMenuItem("save"));
mnu.add(new JMenuItem("print"));
final JLabel la=new JLabel("click",JLabel.CENTER);
la.addMouseListener(new java.awt.event.MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
mnu.show(la,e.getX(),e.getY());
}
});
this.getContentPane().add(la);
pack();
show();
}

public static void main(String args[])
{
PopupMenu PopupMenu= new PopupMenu("例子");

PopupMenu.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e)
{
System.exit(0);
}
});
}
}

Answer 2

pack();  －－－>setSize(300,200);
show();  －－－>setVisible(true);把上面两行改一下，更容易看，show()方法好像已经不推荐使用了吧，用setVisible(true);代替

Answer 3

PopupMenu PopupMenu= new PopupMenu("例子");//不好！对象名与类名一样！！建议改为：PopupMenu PopupMenuOne = new PopupMenu("例子");
PopupMenuOne.addWindowListener

Answer 4

对上面程序进行改进一下，右键弹出菜单import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.border.*;public class PopupMenu
    extends JFrame
{    public PopupMenu(String strTitle)
    {
        super(strTitle);
        final JPopupMenu mnu = new JPopupMenu();
        mnu.add(new JMenuItem("new"));
        mnu.add(new JMenuItem("save"));
        mnu.add(new JMenuItem("print"));
        final JLabel la = new JLabel("click", JLabel.CENTER);
        la.addMouseListener(new java.awt.event.MouseAdapter()
        {
            public void mousePressed(MouseEvent e)
            {
                if (e.getButton() == e.BUTTON3)
                    mnu.show(la, e.getX(), e.getY());
            }            public void mouseReleased(MouseEvent e)
            {
                if (e.getButton() == e.BUTTON3)
                    mnu.show(la, e.getX(), e.getY());
            }            public void mouseClicked(MouseEvent e)
            {
                if (e.getButton() == e.BUTTON3)
                    mnu.show(la, e.getX(), e.getY());
            }        });
        this.getContentPane().add(la);
        pack();
        show();
    }    public static void main(String args[])
    {
        PopupMenu PopupMenu = new PopupMenu("例子");        PopupMenu.addWindowListener(new WindowAdapter()
        {
            public void windowClosing(WindowEvent e)
            {
                System.exit(0);
            }
        });
    }
}