Re: Odd behaviour or normal?

In article <hub7nc$n9r$1@speranza.aioe.org>,
 "Rhino" <no.offline.contact.please@example.com> wrote:


Extending JPanel is reasonable if you're changing the panel's behavior.
Containment using composition is a way to add other JComponents to a
JPanel. In this example, ImagePanel _contains_ a button and some text,
and it _extends_ JPanel to add the ability to draw a background image.

class ImagePanel extends JPanel {

    BufferedImage img;
    JButton button = new JButton();
    JTextField text = new JTextField();

    ImagePanel(String name) {
        super(true);
        button.setText(name);
        this.add(button);
        text.setText(name);
        this.add(text);
        this.setToolTipText(name);
        try {
            img = ImageIO.read(new File(name));
            this.setPreferredSize(new Dimension(
                img.getWidth(), img.getHeight()));
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.drawImage(img, 0, 0, this.getWidth(), this.getHeight(), null);
    }
}


This is controlled by the container's layout manager. Nesting JPanels is
one way to achieve a desired effect:

<http://java.sun.com/docs/books/tutorial/uiswing/layout/index.html>

--
John B. Matthews
trashgod at gmail dot com
<http://sites.google.com/site/drjohnbmatthews>