popupmenutest.java

这是《Java 2 简明教程(第2版)》一书配套的源代码。

import java.awt.*;
    import java.applet.*;
    import java.awt.event.*;
    import java.awt.PopupMenu;

    public class PopupMenuTest extends Applet implements ActionListener {

PopupMenu popup;

public void init() {    
            MenuItem mi;
popup=new PopupMenu("Edit");
            mi = new MenuItem("Cut");
            mi.addActionListener(this);
  popup.add(mi);
            mi = new MenuItem("Copy");
            mi.addActionListener(this);
            popup.add(mi);
    popup.addSeparator();
            mi = new MenuItem("Paste");
            mi.addActionListener(this);
    popup.add(mi);
   add(popup); // add popup menu to applet
           
            enableEvents(AWTEvent.MOUSE_EVENT_MASK); 

    resize(200, 200);
        }

public void processMouseEvent(MouseEvent e) {

    if (e.isPopupTrigger()) { 
        popup.show(e.getComponent(), e.getX(), e.getY());
    }
    super.processMouseEvent(e);
        }

        public void actionPerformed(ActionEvent e) {
    String command = e.getActionCommand();

            if (command.equals("Cut")) {
        // perform cut operation
            } else if (command.equals("Copy")) {
                // perform copy operation
            } else if (command.equals("Paste")) {
                // perform paste operation
            }
        }
    }