Implementing the HelloWorldMIDlet

A MIDlet that will display a simple SVG graphic of a "smiley face" using the SvgCanvas1 to render it.

1. Create the HelloWorldMIDlet class file.

2. Import the required classes and assign this class to the com.nokia.midp.examples.svg package.

   /* Copyright © 2006 Nokia. */
   package com.nokia.midp.examples.svg;
   
   
   import javax.microedition.midlet.*;
   import javax.microedition.lcdui.*;

3. Set HelloWorldMIDlet to extend midlet and to implement CommandListener.

    /**
    * Simple midlet that displays a static SVG file.
    */
    public class HelloWorldMIDlet extends MIDlet implements CommandListener {

4. Write the below code to construct the Midlet. Create a new SvgCanvas1 object for building the actual image.

   /**
   * Constructor.
   */
       public HelloWorldMIDlet() {
       	
           // *** create the SVG canvas
           svgCanvas = new SvgCanvas1 (false);
           svgCanvas.setCommandListener(this);
           
   
   		  // *** grab a reference to the display
           display = Display.getDisplay(this);
           display.setCurrent(svgCanvas);
   

   Add Commands for exiting and zooming the image.

           
           // *** set up the midlet menu
           int hotKey = 0;
           
           cmZoomIn = new Command("Zoom In", Command.SCREEN, hotKey++);
           svgCanvas.addCommand(cmZoomIn);
           
           cmZoomOut = new Command("Zoom Out", Command.SCREEN, hotKey++);
           svgCanvas.addCommand(cmZoomOut);
   
           cmExit = new Command("Exit", Command.SCREEN, hotKey++);
           svgCanvas.addCommand(cmExit);
       }

5. Add the following three required methods.

   	 /**
   	 * Required midlet method.
   	 */
       public void startApp() {
       }
   
   
   	 /**
   	 * Required midlet method.
   	 */
       public void pauseApp() {
       }
   
       
   	 /**
   	 * Required midlet method.
   	 */
       public void destroyApp(boolean unconditional) {
       }

6. Add the Command actions for zoom and exit functions.

      public void commandAction(Command c, Displayable s) {
           if (c == cmExit) {
               destroyApp(false);
               notifyDestroyed();
           }   else if ( c == cmZoomIn ) {
                   svgCanvas.zoomIn();
           }   else if ( c == cmZoomOut ) {
                   svgCanvas.zoomOut();
           }
       }
   

   Initiate the private objects.

   
   	 /*
   	 * Private members
   	 */
   
       private Display display;
       private SvgCanvas1 svgCanvas;
   
       private Command cmExit;
       private Command cmZoomIn;
       private Command cmZoomOut;
   }