Java Swing Look and Feel checkGTKLookAndFeel()

Description

Look and feel improvement on Ubuntu http://stackoverflow.com/questions/3907047/how-to-change-the-default-font -size-in-the-swing-gtk-lookandfeel/31345102#31345102

License

GNU General Public License

Exception

Parameter	Description
Exception	an exception

Declaration

public static void checkGTKLookAndFeel() throws Exception 

Method Source Code

//package com.java2s;
/**//ww  w.  j  a va2 s.  co  m
 * License: GPL
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License 2
 * as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

import java.awt.Font;
import java.lang.reflect.Field;

import java.util.Map;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JRadioButton;
import javax.swing.JSlider;
import javax.swing.JSpinner;
import javax.swing.JTabbedPane;
import javax.swing.JTable;
import javax.swing.JTextArea;
import javax.swing.JTextField;
import javax.swing.JToggleButton;
import javax.swing.LookAndFeel;
import javax.swing.UIManager;
import javax.swing.plaf.FontUIResource;

public class Main {
    /**
     * Look and feel improvement on Ubuntu
     *
     * http://stackoverflow.com/questions/3907047/how-to-change-the-default-font
     * -size-in-the-swing-gtk-lookandfeel/31345102#31345102
     *
     * @throws Exception
     */
    public static void checkGTKLookAndFeel() throws Exception {
        final LookAndFeel look = UIManager.getLookAndFeel();
        if (!look.getID().equals("GTK"))
            return;

        new JFrame();
        new JButton();
        new JComboBox<>();
        new JRadioButton();
        new JCheckBox();
        new JTextArea();
        new JTextField();
        new JTable();
        new JToggleButton();
        new JSpinner();
        new JSlider();
        new JTabbedPane();
        new JMenu();
        new JMenuBar();
        new JMenuItem();

        Object styleFactory;
        final Field styleFactoryField = look.getClass().getDeclaredField("styleFactory");
        styleFactoryField.setAccessible(true);
        styleFactory = styleFactoryField.get(look);

        final Field defaultFontField = styleFactory.getClass().getDeclaredField("defaultFont");
        defaultFontField.setAccessible(true);
        final Font defaultFont = (Font) defaultFontField.get(styleFactory);
        FontUIResource newFontUI;
        newFontUI = new FontUIResource(defaultFont.deriveFont((float) (defaultFont.getSize() - 2f)));
        defaultFontField.set(styleFactory, newFontUI);

        final Field stylesCacheField = styleFactory.getClass().getDeclaredField("stylesCache");
        stylesCacheField.setAccessible(true);
        final Object stylesCache = stylesCacheField.get(styleFactory);
        final Map stylesMap = (Map) stylesCache;
        for (final Object mo : stylesMap.values()) {
            final Field f = mo.getClass().getDeclaredField("font");
            f.setAccessible(true);
            final Font fo = (Font) f.get(mo);
            f.set(mo, fo.deriveFont((float) (fo.getSize() - 2f)));
        }
    }
}

Related

1. applyNimbusLaF()
2. applyStartupLookAndFeel(String desiredLafClassName)
3. checkThemeLiscense(LookAndFeelInfo i)
4. computeIsLafAqua()
5. defaultLookAndFeel()
6. enableLafIfAvailable(String lafName)