How to update / draw JProgressBar while Swing loads, building GUI

Question

I have a GUI that is quite difficult to create / initialize on the platform on which it runs. Therefore, I want to update the progress while it is initializing.

I have a small Unecorated JDialog containing JLabel and JProgressBar that I want to update in certain places during initialization, however, since dispatching the thead event (according to Swing rules) is used to create / initialize the GUI, progress certainly does not update until until the EDT works again (i.e., initialization is complete).

JProgressBar I got to redraw using "paintImmediately", but I can't get it to work correctly for JLabel and the dialog itself. Is there any simple recommended / tested method for this?

amuses ...

EDIT: adding an example of what I'm trying to do; greatly simplified, of course.

private JLabel progressLabel;
private JProgressBar progressBar;

public static int main(String[] args) {
    SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            showProgressDialog();
            progressLabel.setText("construct 1");

            constructSomeHeavyGUI();

            progressLabel.setText("construct 2");
            progressBar.setValue(33);

            constructSomeMoreHeavyGUI();

            progressLabel.setText("construct 3");
            progressBar.setValue(67);

            constructEvenMoreHeavyGUI();

            progressLabel.setText("done");
            progressBar.setValue(100);

            hideProgressDialog();

            showHeavyGUI();

        }
    });
}

replications caused by calls progressBar.setValue()/ progressLabel.setText()above will, of course, be queued while the EDT is busy and will lead to redrawing after we are all done and not updated along the way.

Answer 1

, constructSome*HeavyGUI() , , , , () . GUI SwingWorker . .

. , , invokeLater(), . , . JTable - .

Answer 2

, SwingWorker, JProgressBar EDT - isuees Swing,

Runnable#thread, invokeLater();

:

import java.awt.Dimension;
import java.awt.Toolkit;
import java.awt.Window;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.*;

public class TestProgressBar {

    private static void createAndShowUI() {
        JFrame frame = new JFrame("TestProgressBar");
        frame.getContentPane().add(new TestPBGui().getMainPanel());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        java.awt.EventQueue.invokeLater(new Runnable() {

            @Override
            public void run() {
                createAndShowUI();
            }
        });
    }

    private TestProgressBar() {
    }
}

class TestPBGui {

    private JPanel mainPanel = new JPanel();

    public TestPBGui() {
        JButton yourAttempt = new JButton("WRONG attempt to show Progress Bar");
        JButton myAttempt = new JButton("BETTER attempt to show Progress Bar");
        yourAttempt.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                yourAttemptActionPerformed();
            }
        });
        myAttempt.addActionListener(new ActionListener() {

            @Override
            public void actionPerformed(ActionEvent e) {
                myAttemptActionPerformed();
            }
        });
        mainPanel.add(yourAttempt);
        mainPanel.add(myAttempt);
    }

    private void yourAttemptActionPerformed() {
        Window thisWin = SwingUtilities.getWindowAncestor(mainPanel);
        JDialog progressDialog = new JDialog(thisWin, "Uploading...");
        JPanel contentPane = new JPanel();
        contentPane.setPreferredSize(new Dimension(300, 100));
        JProgressBar bar = new JProgressBar(0, 100);
        bar.setIndeterminate(true);
        contentPane.add(bar);
        progressDialog.setContentPane(contentPane);
        progressDialog.pack();
        progressDialog.setLocationRelativeTo(null);
        Task task = new Task("Your attempt");
        task.execute();
        progressDialog.setVisible(true);
        while (!task.isDone()) {
        }
        progressDialog.dispose();
    }

    private void myAttemptActionPerformed() {
        Window thisWin = SwingUtilities.getWindowAncestor(mainPanel);
        final JDialog progressDialog = new JDialog(thisWin, "Uploading...");
        JPanel contentPane = new JPanel();
        contentPane.setPreferredSize(new Dimension(300, 100));
        final JProgressBar bar = new JProgressBar(0, 100);
        bar.setIndeterminate(true);
        contentPane.add(bar);
        progressDialog.setContentPane(contentPane);
        progressDialog.pack();
        progressDialog.setLocationRelativeTo(null);
        final Task task = new Task("My attempt");
        task.addPropertyChangeListener(new PropertyChangeListener() {

            @Override
            public void propertyChange(PropertyChangeEvent evt) {
                if (evt.getPropertyName().equalsIgnoreCase("progress")) {
                    int progress = task.getProgress();
                    if (progress == 0) {
                        bar.setIndeterminate(true);
                    } else {
                        bar.setIndeterminate(false);
                        bar.setValue(progress);
                        progressDialog.dispose();
                    }
                }
            }
        });
        task.execute();
        progressDialog.setVisible(true);
    }

    public JPanel getMainPanel() {
        return mainPanel;
    }
}

class Task extends SwingWorker<Void, Void> {

    private static final long SLEEP_TIME = 4000;
    private String text;

    public Task(String text) {
        this.text = text;
    }

    @Override
    public Void doInBackground() {
        setProgress(0);
        try {
            Thread.sleep(SLEEP_TIME);// imitate a long-running task
        } catch (InterruptedException e) {
        }
        setProgress(100);
        return null;
    }

    @Override
    public void done() {
        System.out.println(text + " is done");
        Toolkit.getDefaultToolkit().beep();
    }
}

EDIT:

1) : Fly/Runtime, , removeAll()

2) , , , JProgressBars JTable

3) paintImmediately(), , - JLabel, JProgressBar#setValue(int);

Answer 3

SwingUtilities.invokeAndWait invokeLater .

Answer 4

SwingUtilities.invokeLater(...), @StanislavL, SwingWorker.

. :

• SwingWorker