How to change background color of jDesktopPane whi

By unsing netbeans ide , I created a JDesktopPane inside the JFrame. and I cannot change the color of the jdesktopPane.. I tried all I can. But when I open the JFrame .. the JDesktopPane inside that JFrame is in some blue color background.

Please help me to change the background of JDesktopPane

I'm going to assume you're using GUI Builder with the default Nimbus look and feel (because you said you've tried everything, and I'll assume you've tried setBackground). The look and feel has the background set. But you have options around it.

You can just paint the background. You want to look at this answer for how to edit the auto-generated code. Then you can just to this, when you edit the code. Don't forget to hit
ctrl+shift+I afterwards, to resolve all imports. I'm too lazy to write fully qualified names.
```
jDesktopPane1 = new javax.swing.JDesktopPane() {
    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.setColor(Color.BLACK);
        g.fillRect(0, 0, getWidth(), getHeight());
    }
};
```

If you want an image, you can paint an image

jDesktopPane1 = new javax.swing.JDesktopPane() {
    private Image image;
    {
        try {
            image = ImageIO.read(new URL("http://www.hdbackgroundspoint.com/wp-content/uploads/2013/12/16/345t34.jpeg"));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

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

You could also override the Nimbus default DesktopPane[Enabled].backgroundPainter. See Nimbus Defaults here

public static void main(String[] args) {
    try {

        for (UIManager.LookAndFeelInfo laf : UIManager
                .getInstalledLookAndFeels()) {
            if ("Nimbus".equals(laf.getName())) {
                UIManager.setLookAndFeel(laf.getClassName());
                UIManager.getLookAndFeelDefaults().put(
                        "DesktopPane[Enabled].backgroundPainter",
                        new DesktopPainter());
            }
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            new JDesktopPaneDemo();
        }
    });
}

static class DesktopPainter implements Painter<JComponent> {
    private Image image;

    public DesktopPainter() {
        try {
            image = ImageIO.read(new URL("http://www.hdbackgroundspoint.com/wp-content/uploads/2013/09/hh.jpeg"));
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    @Override
    public void paint(Graphics2D g, JComponent object, int width, int height) {
        g.drawImage(image, 0, 0, width, height, null);
    }
}