How to make JTabbedPane autoresize to fit page dimensions?

teamon picture teamon · Mar 24, 2010 · Viewed 17.2k times · Source

I have only JTabbedPane inside JFrame. JTabbedPane sets its dimensions to biggest page width/height. As pages has different size is it possible to force JTabbedPane to change its dimensions when selecting other page?

http://grab.by/3hIg

Top one is how it behave now and bottom one is how i want it to behave (i resized frame by hand)

Answer

Eugene Ryzhikov picture Eugene Ryzhikov · Mar 24, 2010

This is fairly simple. It involves dynamic calculation of differences between your pages dimensions and the using them to force preferred size on you JTabbedPane. I did a quick experiment and it worked. So instead of putting a lot of text here - here is the code. It is not perfect but you should get an idea. Questions are welcome, of course.

import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

public class Test {

    private static int maxW = 0;
    private static int maxH = 0;

    public static void main(String[] args) {


        final JFrame f = new JFrame();

        final JTabbedPane tabs = new JTabbedPane();

        tabs.add( createPanel(Color.RED, 100, 100), "Red");
        tabs.add( createPanel(Color.GREEN, 200, 200), "Green");
        tabs.add( createPanel(Color.BLUE, 300, 300), "Blue");

        final Dimension originalTabsDim = tabs.getPreferredSize();

        tabs.addChangeListener(new ChangeListener() {

            @Override
            public void stateChanged(ChangeEvent e) {

                Component p =   ((JTabbedPane) e.getSource()).getSelectedComponent();
                Dimension panelDim = p.getPreferredSize();

                Dimension nd = new Dimension(
                        originalTabsDim.width - ( maxW - panelDim.width),
                        originalTabsDim.height - ( maxH - panelDim.height) );

                tabs.setPreferredSize(nd);

                f.pack();
            }

        });

        f.setContentPane(tabs);
        f.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
        f.pack();
        f.setLocationRelativeTo(null);

        f.setVisible(true);


    }

    private static final JPanel createPanel( Color color, int w, int h ) {

        JPanel p = new JPanel();
        p.setBackground(color);
        p.setPreferredSize( new Dimension(w, h));

        maxW = Math.max(w, maxW);
        maxH = Math.max(h, maxH);

        return p;

    }

}