How can I properly center a JPanel ( FIXED SIZE ) inside a JFrame?

Question

Hi all! I\'m trying to solve an -apparently- simple problem, but I cannot fix it. I\'m working on a sample application with Java/Swing libraries; I have a JFrame and a JPan

Answer 1

First of all, thanks to all.

I reply another time to my own question, to show everyone the choice I have made. See the sample code below; As you can see, I have included only minimal steps which are absolutely necessary to achieve the goal.

/* file StackResponse.java */

import java.awt.*;
import javax.swing.*;

public class StackResponse {
    public static void main(String [] args) {

        JPanel panel = new JPanel();
        Dimension expectedDimension = new Dimension(100, 100);

        panel.setPreferredSize(expectedDimension);
        panel.setMaximumSize(expectedDimension);
        panel.setMinimumSize(expectedDimension);

        panel.setBackground(Color.RED); // for debug only

        Box box = new Box(BoxLayout.Y_AXIS);

        box.add(Box.createVerticalGlue());
        box.add(panel);     
        box.add(Box.createVerticalGlue());

        JFrame frame = new JFrame();
        frame.add(box);
        frame.setSize(new Dimension(200, 200));
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        frame.setMinimumSize(frame.getMinimumSize());   // cannot be resized-

        frame.setVisible(true);

    }
}

Here you can see a screenshot.

Problem solved. Many thanks again to all.

IT