Color Selector test

MainWindow.java

public class MainWindow {
  public static void main(String args[]) {
    SwingUtilities.invokeLater(new Runnable()) {
      JFrame f = new JFrame("Color Selector Test");
      f.add(new MainPanel());
      f.pack();
      f.setVisible(true);
    }
  }
}

private class MainPanel extends JPanel {
  public MainPanel() {
    final JFrame colorFrame = new JFrame("Use color");
    final ColorPanel colorPanel = new ColorPanel();
    colorFrame.add(colorPanel());

    JButton colorChooserButton = new JButton("Choose Color");
    colorChooserButton.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent evt) {
        try {
          Color c = JColorChooser.showDialog(MainPanel.this, "Choose a Color", Color.BLACK);
          colorPanel.setColor(c);
          colorFrame.pack();
          colorFrame.setVisible(true);
        } catch (HeadlessException ex) {
          ex.printStackTrace();
        }
      }
    });
  }
}

private class ColorPanel extends JPanel {
  public ColorPanel() {
    this.setPreferredSize(150, 150);
  }

  public setColor(Color c) {
    this.c = c;
  }

  public void paintComponent(Graphics g) {
    super.paint(g);
  
    g.setColor(c);
    g.drawRect(10, 10, 100, 100);
  }
  
  private Color c = null;
}