package swingtest;

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

public class LayoutTest extends JFrame
{
    public LayoutTest()
    {
        //same for everyone, just copy and paste
        super("Layout Test");
        setSize(800, 600); //frame size
        setDefaultCloseOperation(EXIT_ON_CLOSE); //close frame on exit action
        Container contentPane = this.getContentPane();

        //-----here is the problem.
        //This layout just pack everything in one row, no size preservation
        //upon resizing, unless we set those sizes.
        //reference: http://java.sun.com/docs/books/tutorial/uiswing/layout/box.html
        contentPane.setLayout(new BoxLayout(contentPane, BoxLayout.X_AXIS));

        JPanel leftPanel = new JPanel();
        JPanel centerPanel = new JPanel();
        JPanel rightPanel = new JPanel();

        Dimension dim = new Dimension(200, 200);
        //I don't care which to do the trick, just brutal force, so set all of them
        //You may figure out which one does the trick.
        centerPanel.setMinimumSize(dim);
        centerPanel.setMaximumSize(dim);
        centerPanel.setPreferredSize(dim);

        leftPanel.add(new JLabel("Left Panel"));
        leftPanel.setBorder(BorderFactory.createLineBorder(Color.black));
        centerPanel.add(new JTextField("This is center, fixed"));
        centerPanel.setBorder(BorderFactory.createLineBorder(Color.black));
        rightPanel.add(new JButton("right Panel"));
        rightPanel.setBorder(BorderFactory.createLineBorder(Color.black));

        contentPane.add(leftPanel, BorderLayout.WEST);
        contentPane.add(centerPanel, BorderLayout.CENTER);
        contentPane.add(rightPanel, BorderLayout.EAST);
    }

    public static void main(String[] args)
    {
        //same for everyone except the very first line, which should refer
        //to this class
        LayoutTest ttf = new LayoutTest();
        Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
        Dimension frameSize = ttf.getSize();
        if (frameSize.height > screenSize.height) frameSize.height = screenSize.height;
        if (frameSize.width > screenSize.width) frameSize.width = screenSize.width;
        ttf.setLocation((screenSize.width - frameSize.width) / 2, (screenSize.height - frameSize.height) / 2);
        ttf.validate();
        ttf.setVisible(true);
    }

}