//  MenuDemoWithPopupMenuApplication.java  (c) 2006 Kari Laitinen

//  http://www.naturalprogramming.com

//  2006-11-18  File created.
//  2006-11-26  Last modification.

//  This program is a modified version of MenuDemoApplication.java.
//  This version provides a pop-up menu in addition to the traditional
//  menus.

//  The settings of the program can be modified both with a conventional
//  Settings menu and with a popup settings menu. These two menus are
//  simply different menus and they are synchronized in the 
//  actionPerformed() method.

//  At least in a Windows PC, you have to use the RIGHT mouse button to
//  make the pop-up menu active.

//  You'll find more notes at the end of this file.

import java.awt.* ;
import java.awt.event.*;

import javax.swing.* ;


class MenuDemoFrameWithPopupMenu extends JFrame implements ActionListener,
                                                           MouseListener
{
   static final int WINDOW_WIDTH   =  500 ;
   static final int WINDOW_HEIGHT  =  400 ;

   JMenuItem  file_open_menu_item  =  new  JMenuItem( "Open" ) ;
   JMenuItem  file_save_menu_item  =  new  JMenuItem( "Save" ) ;
   JMenuItem  file_exit_menu_item  =  new  JMenuItem( "Exit" ) ;

   JMenuItem  edit_copy_menu_item  =  new  JMenuItem( "Copy" ) ;
   JMenuItem  edit_paste_menu_item =  new  JMenuItem( "Paste" ) ;

   JCheckBoxMenuItem  cyan_background_menu_item  =
                                 new JCheckBoxMenuItem( "Cyan background" ) ;

   JCheckBoxMenuItem  popup_cyan_background_menu_item  =
                                 new JCheckBoxMenuItem( "Cyan background" ) ;

   JRadioButtonMenuItem  small_text_menu_item  =
                                 new JRadioButtonMenuItem( "Small" ) ;
   JRadioButtonMenuItem  medium_text_menu_item  =
                                 new JRadioButtonMenuItem( "Medium" ) ;
   JRadioButtonMenuItem  large_text_menu_item  =
                                 new JRadioButtonMenuItem( "Large" ) ;

   ButtonGroup  text_size_button_group  =  new  ButtonGroup() ;

   JRadioButtonMenuItem  popup_small_text_menu_item  =
                                 new JRadioButtonMenuItem( "Small" ) ;
   JRadioButtonMenuItem  popup_medium_text_menu_item  =
                                 new JRadioButtonMenuItem( "Medium" ) ;
   JRadioButtonMenuItem  popup_large_text_menu_item  =
                                 new JRadioButtonMenuItem( "Large" ) ;

   ButtonGroup  popup_text_size_button_group  =  new  ButtonGroup() ;

   JMenuItem  about_menu_item  =  new  JMenuItem( "About" ) ;

   String  last_selected_menu_item  =  "NO SELECTIONS MADE." ;

   JPopupMenu  popup_settings_menu  =  new  JPopupMenu() ;


   public MenuDemoFrameWithPopupMenu()
   {
      getContentPane().setBackground( Color.white ) ;

      setSize( WINDOW_WIDTH, WINDOW_HEIGHT ) ;

      setTitle( "GUI APPLICATION WITH MENUS" ) ;

      file_open_menu_item.setMnemonic( 'O' ) ;
      file_open_menu_item.addActionListener( this ) ;
      file_save_menu_item.setMnemonic( 'S' ) ;
      file_save_menu_item.addActionListener( this ) ;
      file_exit_menu_item.setMnemonic( 'x' ) ;
      file_exit_menu_item.addActionListener( this ) ;

      JMenu  file_menu  =  new  JMenu( "File" ) ;
      file_menu.setMnemonic( 'F' ) ;

      file_menu.add( file_open_menu_item ) ;
      file_menu.add( file_save_menu_item ) ;
      file_menu.add( file_exit_menu_item ) ;

      edit_copy_menu_item.addActionListener( this ) ;
      edit_paste_menu_item.addActionListener( this ) ;

      JMenu  edit_menu  =  new  JMenu( "Edit" ) ;

      edit_menu.add( edit_copy_menu_item ) ;
      edit_menu.add( edit_paste_menu_item ) ;

      JMenu  settings_menu  =  new  JMenu( "Settings" ) ;

      cyan_background_menu_item.addActionListener( this ) ;

      settings_menu.add( cyan_background_menu_item ) ;

      small_text_menu_item.addActionListener( this ) ;
      medium_text_menu_item.addActionListener( this ) ;
      large_text_menu_item.addActionListener( this ) ;

      medium_text_menu_item.setSelected( true ) ;

      text_size_button_group.add( small_text_menu_item ) ;
      text_size_button_group.add( medium_text_menu_item ) ;
      text_size_button_group.add( large_text_menu_item ) ;

      JMenu  text_size_menu  =  new  JMenu( "Text size" ) ;
      
      text_size_menu.add( small_text_menu_item ) ;
      text_size_menu.add( medium_text_menu_item ) ;
      text_size_menu.add( large_text_menu_item ) ;

      settings_menu.add( text_size_menu ) ;

      JMenu  help_menu  =  new  JMenu( "Help" ) ;

      about_menu_item.addActionListener( this ) ;
      help_menu.add( about_menu_item ) ;

      JMenuBar menubar_of_this_window  =  new JMenuBar() ;

      menubar_of_this_window.add( file_menu ) ;
      menubar_of_this_window.add( edit_menu ) ;
      menubar_of_this_window.add( settings_menu ) ;
      menubar_of_this_window.add( help_menu ) ;

      setJMenuBar( menubar_of_this_window ) ;

      setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE ) ;

      //  Let's build the popup menu.

      popup_cyan_background_menu_item.addActionListener( this ) ;

      popup_settings_menu.add( popup_cyan_background_menu_item ) ;

      popup_small_text_menu_item.addActionListener( this ) ;
      popup_medium_text_menu_item.addActionListener( this ) ;
      popup_large_text_menu_item.addActionListener( this ) ;

      popup_medium_text_menu_item.setSelected( true ) ;

      popup_text_size_button_group.add( popup_small_text_menu_item ) ;
      popup_text_size_button_group.add( popup_medium_text_menu_item ) ;
      popup_text_size_button_group.add( popup_large_text_menu_item ) ;

      JMenu  popup_text_size_menu  =  new  JMenu( "Text size" ) ;
      
      popup_text_size_menu.add( popup_small_text_menu_item ) ;
      popup_text_size_menu.add( popup_medium_text_menu_item ) ;
      popup_text_size_menu.add( popup_large_text_menu_item ) ;

      popup_settings_menu.add( popup_text_size_menu ) ;

      addMouseListener(this);
   }


   //  This program implements the MouseListener interface.
   //  The pop-up menu will be shown when the mouse is pressed and
   //  released. It may not be absolutely necessary to have the 
   //  pop-up menu activation in the mousePressed() method.


   public void mouseClicked( MouseEvent event ) {}
   public void mouseEntered( MouseEvent event ) {}
   public void mouseExited( MouseEvent event ) {}

   public void mousePressed( MouseEvent event )
   {
      if ( event.isPopupTrigger() )
      {
         popup_settings_menu.show( event.getComponent(), event.getX(),
                                                         event.getY() ) ;
      }
   }

   public void mouseReleased( MouseEvent event )
   {
      if ( event.isPopupTrigger() )
      {
         popup_settings_menu.show( event.getComponent(), event.getX(),
                                                         event.getY() ) ;
      }
   }

   //  The following method reacts to the menu selections.
   //  In most cases the only reaction is that the text that
   //  appears on the screen is changed.
   //  Background color is set to cyan if that selection is made.
   //  Help -> About selection brings a message dialog to the screen.
   //  File -> Exit selection terminates the application.

   public void actionPerformed( ActionEvent event )
   {
      if ( event.getSource() instanceof JMenuItem )
      {
         JMenuItem selected_menu_item  = (JMenuItem) event.getSource() ;

         //  The following long if ... else if ... else if .... construct
         //  ensures the synchronization between the conventional Settings
         //  menu and the popup Settings menu. All possible Settings selections
         //  are tested and, if necessary, the setting is copied from
         //  the conventional menu to the popup menu or vice versa.

         if ( selected_menu_item  ==  popup_cyan_background_menu_item )
         {
            cyan_background_menu_item.setState(
                           popup_cyan_background_menu_item.getState() ) ;
         }
         else if ( selected_menu_item  ==  cyan_background_menu_item )
         {
            popup_cyan_background_menu_item.setState(
                           cyan_background_menu_item.getState() ) ;
         }
         else if ( selected_menu_item  ==  popup_small_text_menu_item )
         {
            small_text_menu_item.setSelected( true ) ;
         }
         else if ( selected_menu_item  ==  popup_medium_text_menu_item )
         {
            medium_text_menu_item.setSelected( true ) ;
         }
         else if ( selected_menu_item  ==  popup_large_text_menu_item  )
         {
            large_text_menu_item.setSelected( true ) ;
         }
         else if ( selected_menu_item  ==  small_text_menu_item )
         {
            popup_small_text_menu_item.setSelected( true ) ;
         }
         else if ( selected_menu_item  ==  medium_text_menu_item )
         {
            popup_medium_text_menu_item.setSelected( true ) ;
         }
         else if ( selected_menu_item  ==  large_text_menu_item  )
         {
            popup_large_text_menu_item.setSelected( true ) ;
         }


         last_selected_menu_item  =  selected_menu_item.getText() ;

         if ( cyan_background_menu_item.isSelected() == true )
         {
            getContentPane().setBackground( Color.cyan ) ;
         }
         else
         {
            getContentPane().setBackground( Color.white ) ;
         }

         if ( selected_menu_item  ==  file_exit_menu_item )
         {
            setVisible( false ) ;
            System.exit( 0 ) ;
         }
         else if ( selected_menu_item  ==  about_menu_item )
         {
            JOptionPane.showMessageDialog( this, 
                                 "This is a simple GUI application"
                               + "\nwith menus.",
                                 "About", JOptionPane.PLAIN_MESSAGE ) ;
         }

         repaint() ;
      }
   }


   public void paint( Graphics graphics )
   {
      super.paint( graphics ) ;

      if ( small_text_menu_item.isSelected() == true )
      {
         graphics.setFont( new Font( "Serif", Font.PLAIN, 10 ) ) ;
      }

      if ( medium_text_menu_item.isSelected() == true )
      {
         graphics.setFont( new Font( "Serif", Font.PLAIN, 14 ) ) ;
      }

      if ( large_text_menu_item.isSelected() == true )
      {
         graphics.setFont( new Font( "Serif", Font.PLAIN, 18 ) ) ;
      }

      graphics.drawString( "Last selected menu item: \""
                        +   last_selected_menu_item  +  "\"",
                           100, 200 ) ;
   }
}

public class MenuDemoWithPopupMenuApplication
{
   public static void main( String[] not_in_use )
   {
      MenuDemoFrameWithPopupMenu  this_application_window  =
                                     new  MenuDemoFrameWithPopupMenu() ;

      this_application_window.setVisible( true ) ;
   }
}


/*  NOTES:


   The development of this program was somewhat problematic.
   Java textbooks advice that operations that can be activated in 
   two ways, i.e., through conventional menus and popup menus,
   should be based on special action classes, such as the following

class SettingsAction extends AbstractAction
{
   public SettingsAction( String action_name )
   {
      super( action_name ) ;
   }

   public void actionPerformed( ActionEvent event )
   {
      if ( event.getSource() instanceof JMenuItem )
      {
         
         System.out.print( "\n  "  +  getValue( Action.NAME ) ) ;

      }
   }
   
}

   When this kind of a class is defined, it is possible to specify
   menu items in the following way:


   Action  cyan_background_action  =  new  SettingsAction( "Cyan background" );

   JCheckBoxMenuItem  cyan_background_menu_item  =
                           new JCheckBoxMenuItem( cyan_background_action ) ;

   JCheckBoxMenuItem  popup_cyan_background_menu_item  =
                           new JCheckBoxMenuItem( cyan_background_action ) ;

   Action  small_text_action   =  new  SettingsAction( "Small" ) ;
   Action  medium_text_action  =  new  SettingsAction( "Medium" ) ;
   Action  large_text_action   =  new  SettingsAction( "Large" ) ;

   JRadioButtonMenuItem  small_text_menu_item  =
                            new JRadioButtonMenuItem( small_text_action ) ;
   JRadioButtonMenuItem  medium_text_menu_item  =
                            new JRadioButtonMenuItem( medium_text_action ) ;
   JRadioButtonMenuItem  large_text_menu_item  =
                            new JRadioButtonMenuItem( large_text_action ) ;

   JRadioButtonMenuItem  popup_small_text_menu_item  =
                            new JRadioButtonMenuItem( small_text_action ) ;
   JRadioButtonMenuItem  popup_medium_text_menu_item  =
                            new JRadioButtonMenuItem( medium_text_action ) ;
   JRadioButtonMenuItem  popup_large_text_menu_item  =
                            new JRadioButtonMenuItem( large_text_action ) ;

   However, the use of action objects does not help much when
   we use menu items that represent ON/OFF selections or group selections.
   Because of this reason I ended up not using action objects.


*/