Set Composite on a JComponent

Question

So I posted this on the java ranch forums... http://www.coderanch.com/t/440197/Swing-AWT-SWT-JFace/java/Compositing-every-component-Component
and have received no answer. However maybe I was not making my self entirely clear. Here is what I want to do... Using JButton as an example...
but = new JButton("head");
gd = (Graphics2D)but.getGraphics();
gd.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, .5f)); This does not work for me and was wondering what exactly I should do to set the composite of any jcomponent?
Sincerely,
Chris Dancy

Answer 1

I do that, but it´s hard posted here, because the size of the code...
global variable
float alphaPanel = 1f;
painel p;in the constructor
p = new painel();I create the jPanel2 in netbeans6.5...
and then,
jPanel2 = p;this is the panel...
  class painel extends JPanel {
        painel() {
                      setSize(400, 400);
        public void paintComponent(Graphics g) {
            //  System.out.println("pintando "+alphaPanel);
            ((Graphics2D) g).setComposite(
                    AlphaComposite.getInstance(AlphaComposite.SRC_OVER,
                    alphaPanel));
            g.setColor(getBackground());
            g.fillRect(0, 0, getWidth(), getHeight());
    }this is the timer...
javax.swing.Timer timerFadeOutPanel = new javax.swing.Timer(100, new ActionListener() {
        public void actionPerformed(ActionEvent e) {
            alphaPanel -= 0.1f;
            System.out.println(alphaPanel);
            if (alphaPanel < 0) {
                alphaPanel = 0;
                timerFadeOutPanel.stop();
                invisivelPanel();
                p.repaint();
            // p.setVisible(false);
            // timerFadeInPanel.start();
            p.repaint();
// this is the jbuttons etc which should be setVisible(false)...
        private void invisivelPanel() {
            fade2button.setVisible(false);
            fadeButton.setVisible(false);
            fadeInButton.setVisible(false);
            buttonFadeOutPanel.setVisible(false);
            transpbutton.setVisible(false);
            fadeOutButton.setVisible(false);
            jSlider1.setVisible(false);
    });here the jbutton... call method that overhide jpanel
  if (alphaPanel == 1f) {
            p.setOpaque(false);
            alphaPanel = 1f;
            timerFadeOutPanel.start();
        }