Can't transparent and undecorated JFrame in JDK7 when enabling nimbus

Look at this picture :

here is the code that transparent's the frame:

GraphicsEnvironment ge = 
        GraphicsEnvironment.getLocalGraphicsEnvironment();
        GraphicsDevice gd = ge.getDefaultScreenDevice();

        if (!gd.isWindowTranslucencySupported(TRANSLUCENT)) {
            System.err.println(
                "Translucency is not supported");
                System.exit(0);
        }

        JFrame.setDefaultLookAndFeelDecorated(true);

this works good but when trying to enable LookAndFeel by adding

    try {
    for (javax.swing.UIManager.LookAndFeelInfo info : javax.swing.UIManager.getInstalledLookAndFeels()) {
         if ("Nimbus".equals(info.getName())) {
            javax.swing.UIManager.setLookAndFeel(info.getClassName());
            break;
          }
    }
}catch(.......)

it gives me this error

Exception in thread "AWT-EventQueue-0" java.awt.IllegalComponentStateException: The frame is decorated

What's this error ? and how to solve it ?

Thanks for your answers and suggestions.

EDIT

Question Asked/CrossPosted

• OTN

• Daniweb

• CodeRanch