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    import java.awt.*;

    public class ProgressBar extends Frame
    {
        private              int Count;
        private              int Max;
        private static final int FrameBottom = 24;

        public ProgressBar (String Title, int TotalItems)
        {
            super(Title);

            Count = 0;
            Max   = TotalItems;

            // Allowing this to be resized causes more trouble than it is worth
            // and the goal is for this to load and launch quickly!
            setResizable(false);

            setLayout(null);
            addNotify();
            resize (insets().left + insets().right + 379,
                    insets().top + insets().bottom + FrameBottom);
        }

        public synchronized void show()
        {
            move(50, 50);
            super.show();
        }

        // Update the count and then update the progress indicator.  If we have
        // updated the progress indicator once for each item, dispose of the
        // progress indicator.
        public void updateProgress ()
        {
            ++Count;

            if (Count == Max)
                dispose();
            else
                repaint();
        }

        // Paint the progress indicator.
        public void paint (Graphics g)
        {
            Dimension FrameDimension  = size();
            double    PercentComplete = (double)Count * 100.0 /(double)Max;
            int       BarPixelWidth   = (FrameDimension.width * Count)/ Max;

            // Fill the bar the appropriate percent full.
            g.setColor (Color.red);
            g.fillRect (0, 0, BarPixelWidth, FrameDimension.height);

            // Build a string showing the % completed as a numeric value.
            String s        = String.valueOf((int)PercentComplete) + " %";

            // Set the color of the text.  If we don't, it appears in the same color
            // as the rectangle making the text effectively invisible.
            g.setColor (Color.black);

            // Calculate the width of the string in pixels.  We use this to center
            // the string in the progress bar window.
            FontMetrics fm       = g.getFontMetrics(g.getFont());
            int StringPixelWidth = fm.stringWidth(s);

            g.drawString(s, (FrameDimension.width - StringPixelWidth)/2, FrameBottom);
        }

        public boolean handleEvent(Event event)
        {
            if (event.id == Event.WINDOW_DESTROY)
            {
                dispose();
                return true;
            }

         return super.handleEvent(event);
        }
    }

    class ClassPreLoader
    {
        public ClassPreLoader(ProgressBar theProgressBar, String classArray[])
        {
            int i;
            for (i = 0; i < classArray.length; ++ i)
            {
                try
                {
                    Class c = Class.forName(classArray[i]);

                    theProgressBar.updateProgress();
                }
                catch (Exception e)
                {
                    // Do nothing.
                }
            }
        }
    }

    import java.awt.*;
    import java.applet.*;

    public class MyApplet extends Applet
    {
        public void init()
        {
            // The classes needed by your applet.  They have the same
            // name as the *.class files (but without the .class).
            // Don't bother including ClassPreLoader or ProgressBar.
           String classArray[]
             {
                 "FirstClassName",
                 "SecondClassName",
                 "ThirdClassName",
                 // Possible lots more class names in here.
                 "LastClassName"
            };

            super.init();
        setLayout(null);
            resize(6,6);

            // Make and display the progress bar.  The '+2'
            // is because there are two time consuming steps
            // in the constructor of MyAppletRunner, and we
            // update the progress bar inside there, too.
            ProgressBar theProgressBar  =
                new ProgressBar("My nifty applet downloading...", classArray.length + 2);
            theProgressBar.show();

            // Preload all the necessary classes, updating the progress bar as
            // they are loaded.
            ClassPreLoader myPreLoader = new ClassPreLoader(theProgressBar, classArray);

            // The constructor for class MyAppletRunner implements the code that
            // is traditionally in the init() method.
        MyAppletRunner myApplet    = new MyAppletRunner(theProgressBar);
        }

        public boolean handleEvent(Event event)
        {
            return super.handleEvent(event);
        }
    }

Progress bar tutorialBy Anonymous on February 15, 2009, 11:46 pmreally useful

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