ProgressBarStep.java Source code

Introduction

Here is the source code for ProgressBarStep.java

Source

/*
Definitive Guide to Swing for Java 2, Second Edition
By John Zukowski       
ISBN: 1-893115-78-X
Publisher: APress
*/

import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.lang.reflect.InvocationTargetException;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JProgressBar;
import javax.swing.SwingUtilities;

public class ProgressBarStep {
    static class BarThread extends Thread {
        private static int DELAY = 500;

        JProgressBar progressBar;

        public BarThread(JProgressBar bar) {
            progressBar = bar;
        }

        public void run() {
            int minimum = progressBar.getMinimum();
            int maximum = progressBar.getMaximum();
            Runnable runner = new Runnable() {
                public void run() {
                    int value = progressBar.getValue();
                    progressBar.setValue(value + 1);
                }
            };
            for (int i = minimum; i < maximum; i++) {
                try {
                    SwingUtilities.invokeAndWait(runner);
                    // our job for each step is to just sleep
                    Thread.sleep(DELAY);
                } catch (InterruptedException ignoredException) {
                } catch (InvocationTargetException ignoredException) {
                }
            }
        }
    }

    public static void main(String args[]) {
        // Initialize
        final JProgressBar aJProgressBar = new JProgressBar(0, 50);
        aJProgressBar.setStringPainted(true);

        final JButton aJButton = new JButton("Start");

        ActionListener actionListener = new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                aJButton.setEnabled(false);
                Thread stepper = new BarThread(aJProgressBar);
                stepper.start();
            }
        };

        aJButton.addActionListener(actionListener);

        String title = (args.length == 0 ? "Stepping Progress" : args[0]);
        JFrame theFrame = new JFrame(title);
        theFrame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        Container contentPane = theFrame.getContentPane();
        contentPane.add(aJProgressBar, BorderLayout.NORTH);
        contentPane.add(aJButton, BorderLayout.SOUTH);
        theFrame.setSize(300, 200);
        theFrame.setVisible(true);
    }
}