JProgressBar painting issue

Question

When I set the min, value, and max of my JProgressBar they do not update unless I close the window and reopen it.

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Picture:

Can anyone give me any insight? I am scratching my head on this one. I tested to make sure that the parsing is done correctly(which is is). I tested to just put numbers in directly. Clearly it works, it just does not show the first time the window is opened(which makes me think that if I update the values it will only show the last values.

* EDIT *

Ladies and Gentleman... may I present... SSCCE. I am sorry to post this because now you will feel my pain with this :x

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package com.jayavon.game.helper;

import javax.swing.*;
import java.awt.event.*;

public class SSCCE extends JFrame implements WindowListener {

    private static final long serialVersionUID = 1L;
    JFrame frame;
    JPanel panel;
    JButton characterButton;
    JInternalFrame characterFrame;
    /* Character Window */
    JProgressBar totalExpProgressBar;

    Action ClassCharacterButton = new ClassCharacterButton();

    public static void main(String[] args){
        //for thread safety     
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new SSCCE();
            }
        });
    }

    SSCCE() {
        initGUI();
    }

    public void initGUI(){

        frame = new JFrame("SSCCE");
        panel = (JPanel)frame.getContentPane();

        /**********************************
         ** 
         **     Buttons
         **    
         *********************************/
        characterButton = new JButton("");
        characterButton.setBounds(50,175,395,100);
        characterButton.setVisible(true);
        characterButton.getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke("C"), "characterButtonPress");
        characterButton.getActionMap().put("characterButtonPress", ClassCharacterButton);
        characterButton.setAction(ClassCharacterButton);
        characterButton.setText("Click me three times(open/close/open) to get progress bar to fill");
        panel.add(characterButton);

        /**********************************
         ** 
         **     Internal Frames
         **    
         *********************************/
        //#### Character frame start ####
        characterFrame = new JInternalFrame("Character", true, true, false, false);
        characterFrame.setLocation(50, 50);
        characterFrame.setSize(300,105);

        totalExpProgressBar = new JProgressBar();
        totalExpProgressBar.setString("0/0");
        totalExpProgressBar.setStringPainted(true);

        characterFrame.add(totalExpProgressBar);
        characterFrame.setResizable(false);
        panel.add(characterFrame);
        //#### Character frame end ####

        /**********************************
         ** 
         **     Panel Code
         **    
         *********************************/
        panel.setLayout(null);
        panel.setFocusable(true);

        /**********************************
         ** 
         **     Frame Code
         **    
         *********************************/
        frame.setLocation(100, 100);
        frame.setSize(500, 350);
        frame.setVisible(true);
        frame.setFocusable(true);
        frame.addWindowListener(this);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }

    class ClassCharacterButton extends AbstractAction {  
        private static final long serialVersionUID = 1L;

        public void actionPerformed(ActionEvent e) {
            if (characterFrame.isVisible()){
                characterFrame.setVisible(false);
            } else {
                fakeGetServerResponse();
            }
        }
    }

    public void fakeGetServerResponse(){
        String incommingReply = "proskier-charactersWindow@20|10|10|10|0|234|3|200|400"; //fake message from server
        final String splitAt[] = incommingReply.split("@"); //split the character name from the incommingReply at the '@' sign
        String beforeAt[] = splitAt[0].split("-");
        String commandName = beforeAt[1];
        final String afterAt[] = splitAt[1].split("\\|");

        if (commandName.equals("charactersWindow")){
            SwingUtilities.invokeLater(new Runnable() {
                @Override
                public void run() {
                    totalExpProgressBar.setString(afterAt[5] + "/" + afterAt[8]);
                    totalExpProgressBar.setMinimum(0);
                    totalExpProgressBar.setMinimum(Integer.parseInt(afterAt[7])); //TODO::SCREW YOU JAVA
                    totalExpProgressBar.setValue(Integer.parseInt(afterAt[5]));   //TODO::SCREW YOU JAVA
                    totalExpProgressBar.setMaximum(Integer.parseInt(afterAt[8])); //TODO::SCREW YOU JAVA
                    characterFrame.setVisible(true);
                }
            });
        }
    }

    @Override
    public void windowClosing(WindowEvent arg0){
        frame.dispose();
        System.exit(1);
    }
    @Override
    public void windowActivated(WindowEvent arg0) {
    }
    @Override
    public void windowClosed(WindowEvent arg0) {
    }
    @Override
    public void windowDeactivated(WindowEvent arg0) {
    }
    @Override
    public void windowDeiconified(WindowEvent arg0) {           
    }
    @Override
    public void windowIconified(WindowEvent arg0) {
    }
    @Override
    public void windowOpened(WindowEvent arg0) {            
    }
}

Answer 1

You are probably performing work in the EDT (Event Dispatching Thread). This thread has a queue of events and they get dispatched one at a time, sequentially, since AWT is not Thread safe. This allows the UI to update and react to events (either programmtic events such as repaint or invokeLater, or user events such as mouse and key events).

So when you do work in the EDT, you block the Thread and prevent it from dispatching events, such as repaints, clicks, key events, etc...

Usually the solution is to move the work in another Thread, using for example a SwingWorker .

Btw, Thread.sleep(long) is a static method, so no need to call currentThread(), just call Thread.sleep(...) if you need to do so. But again, you should really avoid to do that in the EDT, since it blocks it and will also block the UI.

Answer 2

this is valid for all Swing JComponents , Runnable and Thread.sleep(int) with quasi animations to the GUI

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class ShakingButtonDemo implements Runnable {

    private JButton button;
    private JRadioButton radioWholeButton;
    private JRadioButton radioTextOnly;

    public static void main(String[] args) throws Exception {
        SwingUtilities.invokeLater(new ShakingButtonDemo());
    }

    @Override
    public void run() {
        radioWholeButton = new JRadioButton("The whole button");
        radioTextOnly = new JRadioButton("Button text only");
        radioWholeButton.setSelected(true);
        ButtonGroup bg = new ButtonGroup();
        bg.add(radioWholeButton);
        bg.add(radioTextOnly);
        button = new JButton("  Shake with this Button  ");
        button.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                shakeButton(radioWholeButton.isSelected());
            }
        });
        JPanel p1 = new JPanel();
        p1.setBorder(BorderFactory.createTitledBorder("Shake Options"));
        p1.setLayout(new GridLayout(0, 1));
        p1.add(radioWholeButton);
        p1.add(radioTextOnly);
        JPanel p2 = new JPanel();
        p2.setLayout(new GridLayout(0, 1));
        p2.add(button);
        JFrame frame = new JFrame();
        frame.setTitle("Shaking Button Demo");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.add(p1, BorderLayout.NORTH);
        frame.add(p2, BorderLayout.SOUTH);
        frame.setSize(240, 160);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    private void shakeButton(final boolean shakeWholeButton) {
        final Point point = button.getLocation();
        final Insets margin = button.getMargin();
        final int delay = 75;
        Runnable r = new Runnable() {

            @Override
            public void run() {
                for (int i = 0; i < 30; i++) {
                    try {
                        if (shakeWholeButton) {
                            moveButton(new Point(point.x + 5, point.y));
                            Thread.sleep(delay);
                            moveButton(point);
                            Thread.sleep(delay);
                            moveButton(new Point(point.x - 5, point.y));
                            Thread.sleep(delay);
                            moveButton(point);
                            Thread.sleep(delay);
                        } else {// text only
                            setButtonMargin(new Insets(margin.top, margin.left + 3, margin.bottom, margin.right - 2));
                            Thread.sleep(delay);
                            setButtonMargin(margin);
                            Thread.sleep(delay);
                            setButtonMargin(new Insets(margin.top, margin.left - 2, margin.bottom, margin.right + 3));
                            Thread.sleep(delay);
                            setButtonMargin(margin);
                            Thread.sleep(delay);
                        }
                    } catch (InterruptedException ex) {
                        ex.printStackTrace();
                    }
                }
            }
        };
        Thread t = new Thread(r);
        t.start();
    }

    private void moveButton(final Point p) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                button.setLocation(p);
            }
        });
    }

    private void setButtonMargin(final Insets margin) {
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                button.setMargin(margin);
            }
        });
    }
}

EDIT

example SwingWorker and JProgressBar & SwingWorker#cancel()

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;

public class SwingWorkerExample extends JFrame implements ActionListener {

    private static final long serialVersionUID = 1L;
    private final JButton startButton, stopButton;
    private JScrollPane scrollPane = new JScrollPane();
    private JList listBox = null;
    private DefaultListModel listModel = new DefaultListModel();
    private final JProgressBar progressBar;
    private mySwingWorker swingWorker;

    public SwingWorkerExample() {
        super("SwingWorkerExample");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        getContentPane().setLayout(new GridLayout(2, 2));
        startButton = makeButton("Start");
        stopButton = makeButton("Stop");
        stopButton.setEnabled(false);
        progressBar = makeProgressBar(0, 99);
        listBox = new JList(listModel);
        scrollPane.setViewportView(listBox);
        add(scrollPane);
        //Display the window.
        pack();
        setVisible(true);
    }
//Class SwingWorker<T,V> T - the result type returned by this SwingWorker's doInBackground
//and get methods V - the type used for carrying out intermediate results by this SwingWorker's
//publish and process methods

    private class mySwingWorker extends javax.swing.SwingWorker<ArrayList<Integer>, Integer> {
//The first template argument, in this case, ArrayList<Integer>, is what s returned by doInBackground(),
//and by get(). The second template argument, in this case, Integer, is what is published with the
//publish method. It is also the data type which is stored by the java.util.List that is the parameter
//for the process method, which recieves the information published by the publish method.

        @Override
        protected ArrayList<Integer> doInBackground() {
//Returns items of the type given as the first template argument to the SwingWorker class.
            if (javax.swing.SwingUtilities.isEventDispatchThread()) {
                System.out.println("javax.swing.SwingUtilities.isEventDispatchThread() returned true.");
            }
            Integer tmpValue = new Integer(1);
            ArrayList<Integer> list = new ArrayList<Integer>();
            for (int i = 0; i < 100; i++) {
                for (int j = 0; j < 100; j++) { //find every 100th prime, just to make it slower
                    tmpValue = FindNextPrime(tmpValue.intValue());
//isCancelled() returns true if the cancel() method is invoked on this class. That is the proper way
//to stop this thread. See the actionPerformed method.
                    if (isCancelled()) {
                        System.out.println("SwingWorker - isCancelled");
                        return list;
                    }
                }
//Successive calls to publish are coalesced into a java.util.List, which is what is received by process,
//which in this case, isused to update the JProgressBar. Thus, the values passed to publish range from
//1 to 100.
                publish(new Integer(i));
                list.add(tmpValue);
            }
            return list;
        }//Note, always use java.util.List here, or it will use the wrong list.

        @Override
        protected void process(java.util.List<Integer> progressList) {
//This method is processing a java.util.List of items given as successive arguments to the publish method.
//Note that these calls are coalesced into a java.util.List. This list holds items of the type given as the
//second template parameter type to SwingWorker. Note that the get method below has nothing to do with the
//SwingWorker get method; it is the List's get method. This would be a good place to update a progress bar.
            if (!javax.swing.SwingUtilities.isEventDispatchThread()) {
                System.out.println("javax.swing.SwingUtilities.isEventDispatchThread() + returned false.");
            }
            Integer percentComplete = progressList.get(progressList.size() - 1);
            progressBar.setValue(percentComplete.intValue());
        }

        @Override
        protected void done() {
            System.out.println("doInBackground is complete");
            if (!javax.swing.SwingUtilities.isEventDispatchThread()) {
                System.out.println("javax.swing.SwingUtilities.isEventDispatchThread() + returned false.");
            }
            try {
//Here, the SwingWorker's get method returns an item of the same type as specified as the first type parameter
//given to the SwingWorker class.
                ArrayList<Integer> results = get();
                for (Integer i : results) {
                    listModel.addElement(i.toString());
                }
            } catch (Exception e) {
                System.out.println("Caught an exception: " + e);
            }
            startButton();
        }

        boolean IsPrime(int num) { //Checks whether a number is prime
            int i;
            for (i = 2; i <= num / 2; i++) {
                if (num % i == 0) {
                    return false;
                }
            }
            return true;
        }

        protected Integer FindNextPrime(int num) { //Returns next prime number from passed arg.
            do {
                if (num % 2 == 0) {
                    num++;
                } else {
                    num += 2;
                }
            } while (!IsPrime(num));
            return new Integer(num);
        }
    }

    private JButton makeButton(String caption) {
        JButton b = new JButton(caption);
        b.setActionCommand(caption);
        b.addActionListener(this);
        getContentPane().add(b);
        return b;
    }

    private JProgressBar makeProgressBar(int min, int max) {
        JProgressBar progressBar1 = new JProgressBar();
        progressBar1.setMinimum(min);
        progressBar1.setMaximum(max);
        progressBar1.setStringPainted(true);
        progressBar1.setBorderPainted(true);
        getContentPane().add(progressBar1);
        return progressBar1;
    }

    private void startButton() {
        startButton.setEnabled(true);
        stopButton.setEnabled(false);
        System.out.println("SwingWorker - Done");
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        if ("Start" == null ? e.getActionCommand() == null : "Start".equals(e.getActionCommand())) {
            startButton.setEnabled(false);
            stopButton.setEnabled(true);
// Note that it creates a new instance of the SwingWorker-derived class. Never reuse an old one.
            (swingWorker = new mySwingWorker()).execute(); // new instance
        } else if ("Stop" == null ? e.getActionCommand() == null : "Stop".equals(e.getActionCommand())) {
            startButton.setEnabled(true);
            stopButton.setEnabled(false);
            swingWorker.cancel(true); // causes isCancelled to return true in doInBackground
            swingWorker = null;
        }
    }

    public static void main(String[] args) {
// Notice that it kicks it off on the event-dispatching thread, not the main thread.
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                SwingWorkerExample swingWorkerExample = new SwingWorkerExample();
            }
        });
    }
}

Answer 3

The problem appears to be that you set the progress bar's maximal value after setting its value, and that this will reset the value to the minimum value.

import javax.swing.*;

public class ProgressBarMinValue {
   private static void createAndShowGui() {
      JProgressBar progressBar = new JProgressBar();

      int value = 234;
      int denominator = 400;
      int minValue = 200;
      progressBar.setString(value + "/" + denominator);
      progressBar.setMinimum(minValue);
      System.out.println("value := " + value);

      progressBar.setValue(value);  // (A)

      progressBar.setMaximum(denominator);

      // progressBar.setValue(value);  // (B)

      JPanel mainPanel = new JPanel();
      mainPanel.add(progressBar);

      JOptionPane.showMessageDialog(null, mainPanel);
      System.out.println("progressBar.getValue() := " + progressBar.getValue());
   }

   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
            createAndShowGui();
         }
      });
   }
}

Swap commenting and uncommenting lines (A) and (B) and see that all works well if you set the progress bar's value after setting its minimal and maximal value.

And that's your solution.

Note that I obtained this minimal SSCCE by continuously whittling down your code until the problem could not be reproduced.