//  TickerDemoMIDlet.java  (c) Kari Laitinen

//  http://www.naturalprogramming.com

//  2008-02-05  File created.
//  2008-02-06  Last modification.

//  A Ticker in a midlet is a text that runs on the
//  top of the screen. A Ticker can be attached onto
//  any object that is related to class Displayable.
//  This program shows how a Ticker is attached to a
//  Canvas-based object. Canvas is a subclass of
//  Displayable.

//  This program also demonstrates how commands
//  are added and removed to/from a Canvas.


import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

class TickerDemoCanvas extends Canvas
                       implements CommandListener
{
   int  canvas_width   =  getWidth() ;
   int  canvas_height  =  getHeight() ;

   Command command_to_show_ticker  =  new Command( "Show Ticker",
                                                    Command.SCREEN, 1 ) ;
   Command command_to_remove_ticker  =  new Command( "Remove Ticker",
                                                    Command.SCREEN, 1 ) ;
   Ticker  ticker_to_be_shown  =  new Ticker( "This is a Ticker." ) ;


   public TickerDemoCanvas()
   {
      addCommand( command_to_show_ticker ) ;
      setCommandListener( this ) ;
   }   


   public void commandAction( Command      given_command,
                              Displayable  display_content )
   {
      if ( given_command == command_to_show_ticker )
      {
         setTicker( ticker_to_be_shown ) ;
         removeCommand( command_to_show_ticker ) ;
         addCommand( command_to_remove_ticker ) ;
      }
      else if ( given_command == command_to_remove_ticker )
      {
         setTicker( null ) ;
         removeCommand( command_to_remove_ticker ) ;
         addCommand( command_to_show_ticker ) ;
      }
   }

   public void paint( Graphics graphics )
   {
      graphics.setColor( 0, 0, 0 ) ;  // black color is used for background
      graphics.fillRect( 0, 0, canvas_width, canvas_height ) ;

      graphics.setColor( 255, 255, 255 ) ;  // white color for text

      graphics.drawString( "TickerDemoMIDlet.java", 50, 100,
                           Graphics.TOP | Graphics.LEFT ) ;
   }
}

public class TickerDemoMIDlet extends MIDlet
{
   Display  display_of_this_midlet =  Display.getDisplay( this ) ;
   TickerDemoCanvas  canvas_of_this_midlet =  new  TickerDemoCanvas() ;

   protected void startApp() throws MIDletStateChangeException
   {
      display_of_this_midlet.setCurrent( canvas_of_this_midlet ) ;
   }

   protected void pauseApp()
   {
   }

   protected void destroyApp( boolean unconditional_destruction_required )
   {
   }
}