HTextButton: Different behaviour in HScene and HContainer.

Question

Hi,
i'm trying to use the HTextButton object in a HContainer. But when i'm calling the requestFocus() method of the HTextButton object nothing happens. When i try the same code from the HContainer directly in the HScene everything works fine. I though the HContainer object is used for grouping graphical elements together for easier handling, but i get the strange feeling something is going wrong...
Can someone help me with this?
Here is the code i tryed:
import java.awt.Rectangle;
import org.havi.ui.HContainer;
import org.havi.ui.HTextButton;
public class Quiz extends HContainer {
    HTextButton button1, button2;
    public Quiz(Rectangle screenSize) {
     this.setBounds(screenSize);
     this.setVisible(true);
     button1 = new HTextButton("XXXXXXXXXXXXXXXX", 400, 100, 100, 100);
     button2 = new HTextButton("XXXXXXXXXXXXXXXX", 400, 300, 100, 100);
     button1.setFocusTraversal(button2, button2, button2, button2);
     button2.setFocusTraversal(button1, button1, button1, button1);
     this.add(button1);
     this.add(button2);
     button1.requestFocus();
    }In the Xlet class i'm doing:
import java.awt.Rectangle;
import javax.tv.xlet.Xlet;
import javax.tv.xlet.XletContext;
import javax.tv.xlet.XletStateChangeException;
import org.dvb.dsmcc.InvalidPathNameException;
import org.havi.ui.HScene;
import org.havi.ui.HSceneFactory;
import org.havi.ui.HSceneTemplate;
import org.havi.ui.HTextButton;
public class XletMain implements Xlet {
    private XletContext xletContext;
    private HScene theScene;
    static EPGBackground background = null;
    static Quiz quiz;
    public void initXlet(XletContext xletContext) throws XletStateChangeException {
     System.out.println("[XletMain] Initializing Xlet.");
     this.xletContext = xletContext;
     // Get the HScene.
     HSceneFactory factory = HSceneFactory.getInstance();
     HSceneTemplate hSceneTemplate = new HSceneTemplate();
     if ((theScene = factory.getBestScene(hSceneTemplate)) != null) {
         System.out.println("[Xletmain] HScene created (" + theScene.getBounds().width + "x" +
                      theScene.getBounds().height + ").");
         theScene.setLayout(null);
         background = new EPGBackground(theScene.getBounds());
     } else {
         xletContext.notifyDestroyed();
     quiz = new Quiz(theScene.getBounds());         
    public void startXlet() throws XletStateChangeException {
     System.out.println("[XletMain] Starting Xlet.");
      THIS WORKED FINE:
     HTextButton button1 = new HTextButton("XXXXXXXXXXXXXXXX", 400, 100, 100, 100);
     HTextButton button2 = new HTextButton("XXXXXXXXXXXXXXXX", 400, 300, 100, 100);
     button1.setFocusTraversal(button2, button2, button2, button2);
     button2.setFocusTraversal(button1, button1, button1, button1);
     theScene.add(button1);
     theScene.add(button2);
     button1.requestFocus();
     theScene.add(quiz);
     theScene.setVisible(true);
    public void pauseXlet() {
     System.out.println("[XletMain] Pause Xlet.");
     theScene.setVisible(false);
    public void destroyXlet(boolean unconditional) throws XletStateChangeException {
     System.out.println("[XletMain] Destroying Xlet.");
     xletContext.notifyDestroyed();

Answer 1

if you have lone a component, not added to any container and not visible
on the screen and you call requestFocus(), it sure won't get the focus.
It will get the focus if it is inserted into a top-level container, or
is one of the leaf of an awt tree that has a top-level container
root, if ya' kno' w'at I meen.....
so just try:
public class Quiz extends HContainer { 
  HTextButton button1, button2;   
public Quiz(Rectangle screenSize) {
     this.setBounds(screenSize);
     this.setVisible(true);
     button1 = new HTextButton("XXXXXXXXXXXXXXXX", 400, 100, 100,100);
     button2 = new HTextButton("XXXXXXXXXXXXXXXX", 400, 300, 100, 100);
     button1.setFocusTraversal(button2, button2, button2, button2);
button2.setFocusTraversal(button1, button1, button1, button1);
     this.add(button1);     
    this.add(button2);     
public void requestFocus(){
   button1.requestFocus();  
} then in your Xlet do :
theScene.add(quiz);     
quiz.requestFocus();
theScene.setVisible(true);hope this help...
it is a realy simple problem... call to requestFocus() will have impact on a component that is part of the component tree.