//  MenuDemoApplication.cs  Copyright (c) Kari Laitinen

//  http://www.naturalprogramming.com

//  2008-03-01  File created.
//  2022-12-20  Tested in Developer Command Prompt for VS 2022.

//  This program demonstrates how menus can be built for a C#
//  application.

//  See notes at the end of this file.

using System ;
using System.Windows.Forms ;
using System.Drawing ;

class MenuDemoForm : Form
{
   const int WINDOW_WIDTH   =  800 ;
   const int WINDOW_HEIGHT  =  480 ;

   MenuItem cyan_background_menu_item ;

   MenuItem small_text_menu_item, medium_text_menu_item,
            large_text_menu_item ;


   String  last_selected_menu_item  =  "NO SELECTIONS MADE." ;

   public MenuDemoForm()
   {
      BackColor = Color.White ;

      ClientSize = new Size( WINDOW_WIDTH, WINDOW_HEIGHT ) ;

      Text = "C# GUI APPLICATION WITH MENUS" ; // Window title

      MainMenu main_menu_of_this_window  =  new MainMenu() ;

      MenuItem file_menu = main_menu_of_this_window.MenuItems.Add( "&File" ) ;
      file_menu.MenuItems.Add(
                "&Open", new EventHandler( file_open_selection_made ) ) ;
      file_menu.MenuItems.Add(
                "&Save", new EventHandler( file_save_selection_made ) ) ;
      file_menu.MenuItems.Add(
                "E&xit", new EventHandler( file_exit_selection_made ) ) ;

      MenuItem edit_menu = main_menu_of_this_window.MenuItems.Add( "Edit" ) ;
      edit_menu.MenuItems.Add(
                "Copy", new EventHandler( edit_copy_selection_made ) ) ;
      edit_menu.MenuItems.Add(
                "Paste", new EventHandler( edit_paste_selection_made ) ) ;

      MenuItem settings_menu =
                   main_menu_of_this_window.MenuItems.Add( "Settings" ) ;

      cyan_background_menu_item = new MenuItem( "Cyan background",
                      new EventHandler( cyan_background_selection_made ) ) ;
      settings_menu.MenuItems.Add( cyan_background_menu_item ) ;

      small_text_menu_item = new MenuItem( "Small",
                      new EventHandler( text_size_selection_made ) ) ;
      medium_text_menu_item = new MenuItem( "Medium",
                      new EventHandler( text_size_selection_made ) ) ;
      large_text_menu_item = new MenuItem( "large",
                      new EventHandler( text_size_selection_made ) ) ;

      medium_text_menu_item.Checked = true ; // This is selected by default.

      small_text_menu_item.RadioCheck  = true ;
      medium_text_menu_item.RadioCheck = true ;
      large_text_menu_item.RadioCheck  = true ;

      // The following statement builds a submenu for the Settings menu.

      MenuItem text_size_menu = settings_menu.MenuItems.Add( "Text size" ) ;

      text_size_menu.MenuItems.Add( small_text_menu_item ) ;
      text_size_menu.MenuItems.Add( medium_text_menu_item ) ;
      text_size_menu.MenuItems.Add( large_text_menu_item ) ;

      MenuItem help_menu = main_menu_of_this_window.MenuItems.Add( "Help" ) ;
      help_menu.MenuItems.Add(
                "About", new EventHandler( help_about_selection_made ) ) ;

      // Finally, we'll attach the main menu to the form
      Menu = main_menu_of_this_window ;
   }


   //  The following methods react to the menu selections.
   //  In most cases the only reaction is that the text that
   //  appears on the screen is changed.

   private void file_open_selection_made( Object    sender,
                                          EventArgs event_data )
   {
      last_selected_menu_item  =  "Open" ;
      Invalidate() ;
   }

   private void file_save_selection_made( Object    sender,
                                          EventArgs event_data )
   {
      last_selected_menu_item  =  "Save" ;
      Invalidate() ;
   }

   private void file_exit_selection_made( Object    sender,
                                          EventArgs event_data )
   {
      Close() ; // This terminates the program.
   }

   private void edit_copy_selection_made( Object    sender,
                                          EventArgs event_data )
   {
      last_selected_menu_item  =  "Copy" ;
      Invalidate() ;
   }

   private void edit_paste_selection_made( Object    sender,
                                           EventArgs event_data )
   {
      last_selected_menu_item  =  "Paste" ;
      Invalidate() ;
   }

   private void cyan_background_selection_made( Object    sender,
                                                EventArgs event_data )
   {
      if ( cyan_background_menu_item.Checked == true )
      {
         cyan_background_menu_item.Checked = false ;
         BackColor = Color.White ;
      }
      else
      {
         cyan_background_menu_item.Checked = true ;
         BackColor = Color.Cyan ;
      }

      last_selected_menu_item  =  "Cyan background" ;
      Invalidate() ;
   }

   //  The following method reacts to all text size selections.

   private void text_size_selection_made( Object    sender,
                                          EventArgs event_data )
   {
      if ( sender == small_text_menu_item )
      {
         small_text_menu_item.Checked  = true ;
         medium_text_menu_item.Checked = false ;
         large_text_menu_item.Checked  = false ;
      }
      else if ( sender == medium_text_menu_item )
      {
         small_text_menu_item.Checked  = false ;
         medium_text_menu_item.Checked = true ;
         large_text_menu_item.Checked  = false ;
      }
      else if ( sender == large_text_menu_item )
      {
         small_text_menu_item.Checked  = false ;
         medium_text_menu_item.Checked = false ;
         large_text_menu_item.Checked  = true ;
      }

      last_selected_menu_item  =  "Text size item." ;
      Invalidate() ;
   }

   //  Help -> About selection brings a message dialog to the screen.

   private void help_about_selection_made( Object    sender,
                                           EventArgs event_data )
   {
      MessageBox.Show( "This is a simple GUI application"
                     + "\nwith menus.",
                       "About" ) ;
   }


   protected override void OnPaint( PaintEventArgs paint_data )
   {
      Graphics graphics = paint_data.Graphics ;

      Font font_for_text_line = null ;

      if ( small_text_menu_item.Checked == true )
      {
         font_for_text_line = new Font( FontFamily.GenericSerif, 10 ) ;
      }
      else if ( medium_text_menu_item.Checked == true )
      {
         font_for_text_line = new Font( FontFamily.GenericSerif, 12 ) ;
      }
      else // must be that large_text_menu_item.Checked == true
      {
         font_for_text_line = new Font( FontFamily.GenericSerif, 16 ) ;
      }

      graphics.DrawString( "Last selected menu item: \""
                        +   last_selected_menu_item  +  "\"",
                           font_for_text_line,
                           new SolidBrush( Color.Black ),
                           100, 200 ) ;
   }
}

public class MenuDemoApplication
{
   static void Main()
   {
      Application.Run( new MenuDemoForm() ) ;
   }
}

/* NOTE:

   If you want to add a certain shortcut (accelerator) to a menu item,
   you can specify it in the following way:

      edit_menu.MenuItems.Add( new MenuItem(
                "Copy", new EventHandler( edit_copy_selection_made ),
                Shortcut.CtrlC ) ) ;

*/