Finish painting before Robot captures screen

Question

Hi. I have a little math practice program on a JFrame. When a child gets a problem right, I use Robot to capture a screen shot and then use that image on a new JFrame as a backdrop for crazy effects.
My problem is that I want all swing painting on the original JFrame to finish prior to the Robot screen capture. In particular, the button the child clicks to submit an answer should no longer look 'depressed.' Unfortunately, the Robot screen capture catches the screen before the original JFrame is fully updated/repainted. This occurs despite me putting the call to Robot.createScreenCapture into the EventQueue with invokeLater.
My question is: is there any way to stop and wait until repaint/update is completed, and then proceed with the Robot screen capture?
Thanks for any help.
josh

Answer 1

Thanks for your attention and observations. I should have posted earlier -- I'm getting tangled on words. But it has been instructive.
Here is a sample app. The method submitAnswer is called when the user clicks on the submit button or presses enter when either the textfield or the submit button has the focus. In that method, I attempt to first change the background of a label, and then do a 'special effect' that includes a screen capture. My problem is that the label color change does not happen until after the screen capture.
Thanks again for your assistance.
import java.awt.*;
import java.util.concurrent.*;
import javax.swing.*;
public class MathPractice {
     private JFrame frame;
     private JLabel problem;
     private JTextField answerBox;
     private JButton submit;
     private JLabel scoreLabel;
     private Rectangle screenSize;
     private int score = 0;
     private ScheduledExecutorService scheduler =
               Executors.newScheduledThreadPool(1);
     public void initialize() {
          screenSize = getScreenSize();
          frame = new JFrame("Math Practice");
          frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
          JPanel viewPanel = new JPanel();
          problem = new JLabel("1 + 1");
          Action submitter = new AbstractAction() {
               public void actionPerformed(ActionEvent arg0) {
                    submitAnswer();
          answerBox = new JTextField(3);
          KeyStroke ks = KeyStroke.getKeyStroke(KeyEvent.VK_ENTER, 0);
          answerBox.getInputMap().put(ks, submitter);
          submit = new JButton("Submit");
          submit.addActionListener(submitter);
          submit.getInputMap().put(ks, submitter);
          scoreLabel = new JLabel("0");
          scoreLabel.setOpaque(true);
          viewPanel.add(problem);
          viewPanel.add(answerBox);
          viewPanel.add(submit);
          viewPanel.add(scoreLabel);
          frame.add(viewPanel);
          frame.pack();          
     private void submitAnswer() {
          //correct answer to 1 + 1 :)
          if (answerBox.getText().equals("2")) {
               score++;
               scoreLabel.setText(score + "");
               scoreLabel.setBackground(Color.GREEN);
               specialEffect();
          else {
               scoreLabel.setBackground(Color.ORANGE);
     private void specialEffect() {
          Robot robot = null;
          try {
               robot = new Robot();
          } catch (AWTException e) {
               e.printStackTrace();
               return;
          final BufferedImage screen =
                    robot.createScreenCapture(screenSize);
        final JFrame effectFrame = new JFrame();
        effectFrame.setUndecorated(true);
        JPanel panel = new JPanel() {
            public void paintComponent(Graphics g) {
                 g.drawImage(screen, 0, 0, frame);
                paintMessage("Great", g);
        panel.setPreferredSize(new Dimension(
                  (int) screenSize.getWidth(),
                  (int) screenSize.getHeight()));
        effectFrame.add(panel);
        effectFrame.pack();
        effectFrame.setVisible(true);
        Runnable closer = new Runnable() {
               public void run() {
                    effectFrame.dispose();
        scheduler.schedule(closer, 5000, TimeUnit.MILLISECONDS);
     private Rectangle getScreenSize() {
        GraphicsDevice gd = GraphicsEnvironment.
                  getLocalGraphicsEnvironment().
                  getDefaultScreenDevice();
          DisplayMode dm = gd.getDisplayMode();
          return new Rectangle(dm.getWidth(), dm.getHeight());
     private void paintMessage(String message, Graphics g) {
        Font font = g.getFont().deriveFont(15 * (float)
                  g.getFont().getSize());
        g.setFont(font);
        FontMetrics fm = g.getFontMetrics(font);
        int sw = fm.stringWidth(message);
        int sh = (int) font.getLineMetrics(message,
                  fm.getFontRenderContext()).getHeight();
        int descent = fm.getDescent();
        g.setColor(Color.RED);
        g.drawString(message, (int)(screenSize.getWidth()/2 - sw/2),
                  (int)(screenSize.getHeight()/2 + sh/2 - descent));
     public void setVisible(final boolean b) {
          EventQueue.invokeLater(new Runnable() {
               public void run() {
                    frame.setVisible(b);
     public static void main (String [] args) {
          EventQueue.invokeLater(new Runnable() {
               public void run() {
                    MathPractice mathPractice = new MathPractice();
                    mathPractice.initialize();
                    mathPractice.setVisible(true);
}