How to properly refresh image in JFrame?

Question

This is a problem that disturbs me for few hours now and I\'m not able to find a solution by myself...

I\'ve found similar topics all around the net, but I couldn\'t fin

Answer 1

This is what I came up with:

private static class MyJPanel extends JPanel {
    private Image img = null;

    public MyJPanel() {}

    public void setImage(Image value) {
        if (img != value) {
            Image old = img;
            this.img = value;
            firePropertyChange("image", old, img);
            revalidate();
            repaint();
        }
    }

    public Image getImage() {
        return img;
    }

    @Override
    public Dimension getPreferredSize() {
        return img == null ? new Dimension(200, 200) : new Dimension(img.getWidth(this), img.getHeight(this));
    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        if (img != null) {
            Graphics2D g2d = (Graphics2D) g.create();

            int width = getWidth();
            int height = getHeight();
            double scaleFactor = getScaleFactorToFit(new Dimension(img.getWidth(this), img.getHeight(this)), getSize());
            int x = (int) ((width - (img.getWidth(this) * scaleFactor)) / 2);
            int y = (int) ((height - (img.getHeight(this) * scaleFactor)) / 2);

            AffineTransform at = new AffineTransform();
            at.translate(x, y);
            at.scale(scaleFactor, scaleFactor);
            g2d.setTransform(at);
            g2d.drawImage(img, 0, 0, this);
            g2d.dispose();
        }
    }

    public double getScaleFactor(int iMasterSize, int iTargetSize) {
        return (double) iTargetSize / (double) iMasterSize;
    }

    public double getScaleFactorToFit(Dimension original, Dimension toFit) {
        double dScale = 1d;
        if (original != null && toFit != null) {
            double dScaleWidth = getScaleFactor(original.width, toFit.width);
            double dScaleHeight = getScaleFactor(original.height, toFit.height);
            dScale = Math.min(dScaleHeight, dScaleWidth);
        }
        return dScale;
    }
}

private static class MyJFrame extends JFrame implements Runnable {
    private BufferedImage img = null;
    private MyJPanel panel = null;

    public MyJFrame(BufferedImage image, String title) {
        super(title);
        img = image;
    }

    @Override
    public void run() {
        try {
            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        } catch (ClassNotFoundException | InstantiationException | IllegalAccessException | UnsupportedLookAndFeelException ex) {}

        panel = new MyJPanel();
        panel.setImage(img);

        setLayout(new BorderLayout());
        add(BorderLayout.CENTER, panel);
        setLocation(200, 200);
        setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        pack();
        setVisible(true);
    }

    public void changeImage(BufferedImage image) {
        if ((panel != null) && (panel.getImage() != image)) panel.setImage(image);
    }
}

It's pretty much straightforward copy-paste from example that @MadProgrammer provided.

The only thing left is EDT usage, which is rather magic for me. I'm still invoking this code using dirty way:

MyJFrame mjf = null;
javax.swing.SwingUtilities.invokeLater(mjf = new MyJFrame(buffer, "RDP"));
...
mjf.changeImage(buffer);

My question is: how do I use changeImage method with EDT?