/*
   Chapter 6.5:   Java MenuSystem
   Programmer:    Brad Shedd
   Date:          July 17, 2006
   Filename:      Menusys.java
   Purpose:       This Program has a working menu system and a large text area.
*/

import java.awt.*;
import java.awt.event.*;
import java.awt.datatransfer.*;
import javax.swing.JOptionPane;

public class Menusys extends Frame implements ActionListener
{
   private TextField lcd;
   private boolean clearText;

   public Menusys()
   {
      //construct components and initialize beginning values
      lcd = new TextField (600);

      //create an instance of the menu
      MenuBar mnuBar = new MenuBar();
      setMenuBar(mnuBar);

      //construct and populate the File menu
      Menu mnuFile = new Menu("File", true);
      mnuBar.add(mnuFile);
         MenuItem mnuFileExit = new MenuItem("Exit");
         mnuFile.add(mnuFileExit);

      //construct and populate the Edit menu
      Menu mnuEdit = new Menu("Edit", true);
      mnuBar.add(mnuEdit);
         MenuItem mnuEditClear = new MenuItem("Clear");
         mnuEdit.add(mnuEditClear);
         mnuEdit.insertSeparator(1);
         MenuItem mnuEditCopy = new MenuItem("Copy");
         mnuEdit.add(mnuEditCopy);
         MenuItem mnuEditPaste = new MenuItem("Paste");
         mnuEdit.add(mnuEditPaste);

      //construct and populate teh About menu
      Menu mnuAbout = new Menu ("About", true);
      mnuBar.add(mnuAbout);
         MenuItem mnuAboutCalculator = new MenuItem("About Calculator");
         mnuAbout.add(mnuAboutCalculator);

      //add the ActionListener to each menu item
      mnuFileExit.addActionListener(this);
      mnuEditClear.addActionListener(this);
      mnuEditCopy.addActionListener(this);
      mnuEditPaste.addActionListener(this);
      mnuAboutCalculator.addActionListener(this);

      //assign an ActionCommand to each menu item
      mnuFileExit.setActionCommand("Exit");
      mnuEditClear.setActionCommand("Clear");
      mnuEditCopy.setActionCommand("Copy");
      mnuEditPaste.setActionCommand("Paste");
      mnuAboutCalculator.setActionCommand("About");

      add(lcd, BorderLayout.CENTER);

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

   public void actionPerformed(ActionEvent e)
      {
         //test for menu itme clicks
         String arg = e.getActionCommand();
         if (arg == "Exit")
            System.exit(0);

         if (arg == "Clear")
         {
            clearText = true;
            lcd.setText("");
            lcd.requestFocus();
         }

         if (arg == "Copy")
         {
            Clipboard cb = Toolkit.getDefaultToolkit().getSystemClipboard();
            StringSelection contents = new StringSelection(lcd.getText());
            cb.setContents(contents, null);
         }

      if (arg == "Paste")
      {
         Clipboard cb = Toolkit.getDefaultToolkit().getSystemClipboard();
         Transferable content = cb.getContents(this);
         try
         {
            String s = (String)content.getTransferData(DataFlavor.stringFlavor);
            lcd.setText(s);
         }
         catch (Throwable exc)
         {
            lcd.setText("");
         }
      }


         if (arg == "About")
         {
            String message ="Menusys:\n Giant text box with menus";
            JOptionPane.showMessageDialog(null,message,"AboutCalculator", JOptionPane.INFORMATION_MESSAGE);
         }
      }

   public static void main(String args[])
      {
         // set frame properties
         Menusys f = new Menusys();
         f.setTitle("Menusys");
         f.setBounds(50,130,250,300);
         f.setVisible(true);

      }//end main
}//end class

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