LookAndFeelSwitcher.java

package test.common;

import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.util.Locale;

import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JRootPane;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.UIManager.LookAndFeelInfo;

public class LookAndFeelSwitcher {
	static class LookAndFeelInfoObj {
		LookAndFeelInfo lafInfo;

		String displayName;

		public LookAndFeelInfoObj(LookAndFeelInfo lafInfo, String displayName) {
			this.lafInfo = lafInfo;
			this.displayName = displayName;
		}

		@Override
		public String toString() {
			return displayName;
		}
	}

	public interface LocaleCallback {
		public void onLocaleSelected(Locale selected);
	}

	public static JComboBox getLookAndFeelSwitcher(final JFrame frame) {
		LookAndFeelInfo[] lafs = UIManager.getInstalledLookAndFeels();
		LookAndFeelInfoObj[] lafObjs = new LookAndFeelInfoObj[lafs.length];
		for (int i = 0; i < lafs.length; i++) {
			lafObjs[i] = new LookAndFeelInfoObj(lafs[i], lafs[i].getName());
		}
		final JComboBox result = new JComboBox(lafObjs);
		for (int i = 0; i < lafs.length; i++) {
			if (lafs[i].getName().equals(UIManager.getLookAndFeel().getName())) {
				result.setSelectedIndex(i);
				break;
			}
		}

		result.addItemListener(new ItemListener() {
			public void itemStateChanged(ItemEvent e) {
				SwingUtilities.invokeLater(new Runnable() {
					public void run() {
						boolean wasDecoratedByOS = !frame.isUndecorated();
						try {
							LookAndFeelInfoObj selected = (LookAndFeelInfoObj) result
									.getSelectedItem();
							UIManager.setLookAndFeel(selected.lafInfo
									.getClassName());
							SwingUtilities.updateComponentTreeUI(frame);
						} catch (Exception exc) {
							exc.printStackTrace();
						}
						boolean canBeDecoratedByLAF = UIManager
								.getLookAndFeel()
								.getSupportsWindowDecorations();
						if (canBeDecoratedByLAF == wasDecoratedByOS) {
							boolean wasVisible = frame.isVisible();

							frame.setVisible(false);
							frame.dispose();
							if (!canBeDecoratedByLAF) {
								// see the java docs under the method
								// JFrame.setDefaultLookAndFeelDecorated(boolean
								// value) for description of these 2 lines:
								frame.setUndecorated(false);
								frame.getRootPane().setWindowDecorationStyle(
										JRootPane.NONE);

							} else {
								frame.setUndecorated(true);
								frame.getRootPane().setWindowDecorationStyle(
										JRootPane.FRAME);
							}
							frame.setVisible(wasVisible);
							wasDecoratedByOS = !frame.isUndecorated();
						}
					}
				});
			}
		});

		return result;
	}
}