How to change object background color on java run time

Question

Hi,
I create object loading program. my problem is run time i change object background color using color picker. i select any one color of color picker than submit. The selecting color not assign object background.
pls help me? How to run time change object background color?
here follwing code
import com.sun.j3d.loaders.objectfile.ObjectFile;
import com.sun.j3d.loaders.ParsingErrorException;
import com.sun.j3d.loaders.IncorrectFormatException;
import com.sun.j3d.loaders.Scene;
import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;
import com.sun.j3d.utils.applet.MainFrame;
import com.sun.j3d.utils.universe.*;
import javax.media.j3d.*;
import javax.vecmath.*;
import java.io.*;
import com.sun.j3d.utils.behaviors.vp.*;
import java.net.URL;
import java.net.MalformedURLException;
import java.awt.Graphics ;
import javax.swing.*;
public class ObjLoad1 extends Applet implements ActionListener
private boolean spin = false;
private boolean noTriangulate = false;
private boolean noStripify = false;
private double creaseAngle = 60.0;
private URL filename = null;
private SimpleUniverse u;
private BoundingSphere bounds;
private Panel cardPanel;
private Button Tit,sub;
private CardLayout ourLayout;
private BorderLayout bl;
Background bgNode;
BranchGroup objRoot;
List thelist;
Label l1;
public BranchGroup createSceneGraph()
BranchGroup objRoot = new BranchGroup();
TransformGroup objScale = new TransformGroup();
Transform3D t3d = new Transform3D();
t3d.setScale(0.7);
objScale.setTransform(t3d);
objRoot.addChild(objScale);
TransformGroup objTrans = new TransformGroup();
objTrans.setCapability(TransformGroup.ALLOW_TRANSFORM_WRITE);
objTrans.setCapability(TransformGroup.ALLOW_TRANSFORM_READ);
objScale.addChild(objTrans);
int flags = ObjectFile.RESIZE;
if (!noTriangulate) flags |= ObjectFile.TRIANGULATE;
if (!noStripify) flags |= ObjectFile.STRIPIFY;
ObjectFile f = new ObjectFile(flags,(float)(creaseAngle * Math.PI / 180.0));
Scene s = null;
     try {
          s = f.load(filename);
     catch (FileNotFoundException e) {
     System.err.println(e);
     System.exit(1);
     catch (ParsingErrorException e) {
     System.err.println(e);
     System.exit(1);
     catch (IncorrectFormatException e) {
     System.err.println(e);
     System.exit(1);
     objTrans.addChild(s.getSceneGroup());
     bounds = new BoundingSphere(new Point3d(0.0,0.0,0.0), 100.0);
if (spin) {
     Transform3D yAxis = new Transform3D();
     Alpha rotationAlpha = new Alpha(-1, Alpha.INCREASING_ENABLE,0,0,4000,0,0,0,0,0);
     RotationInterpolator rotator = new RotationInterpolator(rotationAlpha,objTrans,yAxis,0.0f,(float) Math.PI*2.0f);
     rotator.setSchedulingBounds(bounds);
     objTrans.addChild(rotator);
//Background color setting
Color3f bgColor = new Color3f(100,200,230);
bgNode = new Background(bgColor);
bgNode.setApplicationBounds(bounds);
objRoot.addChild(bgNode);
return objRoot;
private void usage()
System.out.println("Usage: java ObjLoad1 [-s] [-n] [-t] [-c degrees] <.obj file>");
System.out.println("-s Spin (no user interaction)");
System.out.println("-n No triangulation");
System.out.println("-t No stripification");
System.out.println("-c Set crease angle for normal generation (default is 60 without");
System.out.println("smoothing group info, otherwise 180 within smoothing groups)");
System.exit(0);
} // End of usage
public void init() {
if (filename == null) {
try {
URL path = getCodeBase();
filename = new URL(path.toString() + "./galleon.obj");
catch (MalformedURLException e) {
     System.err.println(e);
     System.exit(1);
     //setLayout(new BorderLayout());
     //setLayout(new GridLayout(5,0));
     //setLayout(new CardLayout());
     //setLayout(new FlowLayout(FlowLayout.LEFT, 5, 5));
GraphicsConfiguration config = SimpleUniverse.getPreferredConfiguration();
Canvas3D c = new Canvas3D(config);
add(c);
BranchGroup scene = createSceneGraph();
u = new SimpleUniverse(c);
ViewingPlatform viewingPlatform = u.getViewingPlatform();
PlatformGeometry pg = new PlatformGeometry();
Color3f ambientColor = new Color3f(45,27,15);
AmbientLight ambientLightNode = new AmbientLight(ambientColor);
ambientLightNode.setInfluencingBounds(bounds);
pg.addChild(ambientLightNode);
Color3f light1Color = new Color3f(111,222,222);
Vector3f light1Direction = new Vector3f(1.0f, 1.0f, 1.0f);
Color3f light2Color = new Color3f(1.0f, 1.0f, 1.0f);
Vector3f light2Direction = new Vector3f(-1.0f, -1.0f, -1.0f);
DirectionalLight light1 = new DirectionalLight(light1Color, light1Direction);
light1.setInfluencingBounds(bounds);
pg.addChild(light1);
DirectionalLight light2 = new DirectionalLight(light2Color, light2Direction);
light2.setInfluencingBounds(bounds);
pg.addChild(light2);
viewingPlatform.setPlatformGeometry(pg);
viewingPlatform.setNominalViewingTransform();
if (!spin) {
OrbitBehavior orbit = new OrbitBehavior(c,OrbitBehavior.REVERSE_ALL);
BoundingSphere bounds = new BoundingSphere(new Point3d(0.0, 0.0, 0.0), 100.0);
orbit.setSchedulingBounds(bounds);
viewingPlatform.setViewPlatformBehavior(orbit);     
u.addBranchGraph(scene);
     public ObjLoad1(String[] args) {
          if (args.length != 0) {
               for (int i = 0 ; i < args.length ; i++) {
                    if (args.startsWith("-")) {
                         if (args[i].equals("-s")) {
                              spin = true;
                         } else if (args[i].equals("-n")) {
                              noTriangulate = true;
                         } else if (args[i].equals("-t")) {
                              noStripify = true;
                         } else if (args[i].equals("-c")) {
                              if (i < args.length - 1) {
                                   creaseAngle = (new Double(args[++i])).doubleValue();
                              } else usage();
                         } else {
                              usage();
                    } else {
                         try {
                              if ((args[i].indexOf("file:") == 0) ||
                                        (args[i].indexOf("http") == 0)) {
                                   filename = new URL(args[i]);
                              else if (args[i].charAt(0) != '/') {
                                   filename = new URL("file:./" + args[i]);
                              else {
                                   filename = new URL("file:" + args[i]);
                         catch (MalformedURLException e) {
                              System.err.println(e);
                              System.exit(1);
public void actionPerformed(ActionEvent e)
     if (e.getSource() == Tit)
//Color Picker tool
          Color c1 = JColorChooser.showDialog(((Component)e.getSource()).getParent(),"Zaxis Color Picker", Color.blue);
          cardPanel.setBackground(c1);
          objRoot.removeChild(bgNode);
          int a = c1.getRed();
          int b = c1.getBlue();
          int c = c1.getBlue();
          System.out.println(a);
          System.out.println(b);
          System.out.println(c);
          Color3f ccc = new Color3f(a,b,c);
          bgNode.setApplicationBounds(bounds);
     objRoot.addChild(bgNode);
     else
          System.out.println("mathi");
public ObjLoad1()
Tit = new Button("BG Color");
sub = new Button("Object Color");
cardPanel = new Panel();
cardPanel.add(Tit);
cardPanel.add(sub);
//cardPanel.add(l1);
//cardPanel.add(thelist);
sub.addActionListener(this);
Tit.addActionListener(this);
// thelist.addActionListener(this);
//setLayout for applet to be BorderLayout
this.setLayout(new BorderLayout());
//button Panel goes South, card panels go Center
this.add(cardPanel, BorderLayout.SOUTH);
//this.add(cardPanel, BorderLayout.CENTER);     
this.setVisible(true);
public void destroy() {
public static void main(String[] args) {
     new MainFrame(new ObjLoad1(args),400, 400);

Answer 1

hi,
i am using setColor(Color3f color) method
like
if (e.getSource() == Tit)
          Color c1 = JColorChooser.showDialog(((Component)e.getSource()).getParent(),"Zaxis Color Picker", Color.blue);
          bgColor = new Color3f(c1);
          System.out.println(bgColor.get());
     bgNode.setColor(bgColor);
     bgNode.setApplicationBounds(bounds);
     objRoot.addChild(bgNode);
but error will be displayed
like
javax.media.j3d.CapabilityNotSetException: Background: no capability to set color
     at javax.media.j3d.Background.setColor(Background.java:307)
     at ObjLoad1.actionPerformed(ObjLoad1.java:230)
     at java.awt.Button.processActionEvent(Unknown Source)
     at java.awt.Button.processEvent(Unknown Source)
     at java.awt.Component.dispatchEventImpl(Unknown Source)
     at java.awt.Component.dispatchEvent(Unknown Source)
     at java.awt.EventQueue.dispatchEvent(Unknown Source)
     at java.awt.EventDispatchThread.pumpOneEventForHierarchy(Unknown Source)
     at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
     at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
     at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
     at java.awt.EventDispatchThread.run(Unknown Source)
pls help me