Question

i’ve got a java code that shows a background-image. (pizza1.png) I want it to change when i press the arrow keys (case HRcEvent.VK_RIGHT:) But i don’t know what to type so it will redraw the image, it changes the string of the imagepath, but it doesn’t redraw it. Someone can help me?

public class HelloTVXlet implements Xlet, UserEventListener, ResourceClient, HBackgroundImageListener{

   public String afbeelding = "pizza1.png";

    private HScreen screen;
    private HBackgroundDevice bgDevice;
    private HBackgroundConfigTemplate bgTemplate;
    private HStillImageBackgroundConfiguration bgConfiguration;
    private HBackgroundImage agrondimg = new HBackgroundImage(afbeelding);

    public void notifyRelease(ResourceProxy proxy){}
    public void release(ResourceProxy proxy){}
    public boolean requestRelease(ResourceProxy proxy, Object requestData){
    return false;
    }

    public void imageLoaded (HBackgroundImageEvent e){
    try{
    bgConfiguration.displayImage(agrondimg);
    }
    catch (Exception s){
    System.out.println(s.toString());
    }
    }

    public void imageLoadFailed(HBackgroundImageEvent e){
    System.out.println("Image kan niet geladen worden");
    }




    private XletContext actueleXletContext;
    public static HScene scene;
    int waardex = 20;
    int waardey = 20;
    // x; y; 
//   public static MijnComponent mc = new MijnComponent("sterren.PNG");
    // debuggen of niet ?
    private boolean debug=true;

    public HelloTVXlet(){

    }


    public void initXlet(XletContext context) throws XletStateChangeException {

      screen = HScreen.getDefaultHScreen();
      bgDevice = screen.getDefaultHBackgroundDevice();
      if(bgDevice.reserveDevice(this)){

          System.out.println("BackgroundImage device ahs been reserved");
      }
      else{

          System.out.println("Background image device cannot be reserved");

      } 

      bgTemplate = new HBackgroundConfigTemplate();
      bgTemplate.setPreference(HBackgroundConfigTemplate.STILL_IMAGE, HBackgroundConfigTemplate.REQUIRED);

      bgConfiguration = (HStillImageBackgroundConfiguration)bgDevice.getBestConfiguration(bgTemplate);

      try{
      bgDevice.setBackgroundConfiguration(bgConfiguration);
      }catch(java.lang.Exception e){
      System.out.println(e.toString());
      }      




      if(debug) System.out.println("Xlet initialiseren");
      this.actueleXletContext = context;

      HSceneTemplate sceneTemplate = new HSceneTemplate();

      sceneTemplate.setPreference(HSceneTemplate.SCENE_SCREEN_DIMENSION, new HScreenDimension(1.0f, 1.0f), HSceneTemplate.REQUIRED);

      sceneTemplate.setPreference(HSceneTemplate.SCENE_SCREEN_LOCATION, new HScreenPoint(0.0f,0.0f), HSceneTemplate.REQUIRED);

      scene = HSceneFactory.getInstance().getBestScene(sceneTemplate);




    }


    public void startXlet () throws XletStateChangeException {



    agrondimg.load(this);
    if(debug) System.out.println("Xlet starten");

    EventManager manager = EventManager.getInstance();
    UserEventRepository repository = new UserEventRepository("voorbeeld");

    repository.addKey( org.havi.ui.event.HRcEvent.VK_RIGHT);
    repository.addKey( org.havi.ui.event.HRcEvent.VK_LEFT);

    manager.addUserEventListener(this, repository);


    scene.validate();
    scene.setVisible(true);
    }

    public void pauseXlet() {

    }

    public void destroyXlet(boolean unconditional)throws XletStateChangeException {
     agrondimg.flush();
    }

    public void userEventReceived(org.dvb.event.UserEvent e){

        if(e.getType() == KeyEvent.KEY_PRESSED){
        System.out.println("pushed button");
        switch (e.getCode()){


            case HRcEvent.VK_RIGHT:
                System.out.println("vk right");

                if(afbeelding == "pizza1.png"){
                afbeelding = "pizza2.png";

                System.out.println("1 naar 2");

                }else

                if(afbeelding == "pizza2.png"){
                afbeelding = "pizza3.png";

                System.out.println("2 naar 3");
                }else


                if(afbeelding == "pizza3.png"){
                afbeelding = "pizza4.png";

                System.out.println("3 naar 4");
                }else


                if(afbeelding == "pizza4.png"){
                afbeelding = "pizza1.png";

                System.out.println("4 naar 1");
                };


                break;

            case HRcEvent.VK_LEFT:
                System.out.println("vk left");

                break;


        }
        }

    }


}

Answer 1

I think you have to create a new HBackgroundImage object since you cannot change the file once it’s been instantiated. Try:

agrondimg = new HBackgroundImage(afbeelding);
agrondimg.load(this);
try{
    bgConfiguration.displayImage(agrondimg);
} catch (Exception s){
    s.printStackTrace();
}

at the end of the userEventReceived() method.