How to place a button over JFrame title bar

Question

I want to place a button on the JFrame title bar as in the below image.

When I set the bounds for the button using button.setBounds(), the button hides under the title bar as below.

I have given below the code that I had tried.

public class SetBoundsTest {
       public static void main(String arg[]) {
          JFrame frame = new JFrame("Test Frame");
          frame.setSize(500, 250);
          // Setting layout as null
          frame.setLayout(null);
          
          // Creating Button
          JButton button = new JButton("Test");
          // Setting position and size of a button
          button.setBounds(150,-20,120,40);

          button.setBorder(BorderFactory.createLineBorder(Color.BLUE, 3));
          button.setBackground(Color.MAGENTA);
          frame.add(button);
          frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          frame.setLocationRelativeTo(null);
          frame.setVisible(true);
       }
    }

Any help is greatly appreciated.

Answer 1

You can set your frame to undecorated like this

frame.setUndecorated(true);

Note: Add this statement before frame.setVisiblle(true);

Answer 2

Two years late to the party, but I was able to do this without frame.setUndecorated(true) directly using FlatLaf with this tutorial: https://www.youtube.com/watch?v=uWlfe_O12lY

Just keep in mind that FlatLaf may not remain consistent across all systems if used in this manner.

FlatLaf github repo: https://github.com/JFormDesigner/FlatLaf

Launcher

.show() is just a function where I am initializing other panels/objects in my demo project.

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> {
            try {
                FlatLaf.registerCustomDefaultsSource("com.testui.themes");
                FlatDarculaLaf.setup();
                new EpicWindow().show();

            } catch (Exception ex) {
                ...
            }
        });
    }

FlatLaf.properties Config

com/testui/themes/FlatLaf.properties

TitlePane.unifiedBackground=false

The Button!

Then wherever you load your panels into jframe, you need to create a JMenueBar

...
// Just an example..
JButton btn = new JButton("huh?");
JMenuBar menuBar = new JMenuBar();

menuBar.putClientProperty(FlatClientProperties.STYLE, ""
                + "borderColor:$TitlePane.background;"
                + "border:0,0,0,0");

menuBar.add(btn);
jFrameWindow.setJMenuBar(menuBar);
...

Example Image