WindowMenu.java

package org.egonet.mdi;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.beans.PropertyVetoException;

import javax.swing.JCheckBoxMenuItem;
import javax.swing.JInternalFrame;
import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.event.MenuEvent;
import javax.swing.event.MenuListener;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * Menu component that handles the functionality expected of a standard
 * "Windows" menu for MDI applications.
 */
public class WindowMenu extends JMenu {
	
	final private static Logger logger = LoggerFactory.getLogger(WindowMenu.class);
	
	private MDIDesktopPane desktop;

	private JMenuItem cascade = new JMenuItem("Cascade");

	private JMenuItem tile = new JMenuItem("Tile");

	public WindowMenu(MDIDesktopPane desktop) {
		this.desktop = desktop;
		setText("Window");
		cascade.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent ae) {
				WindowMenu.this.desktop.cascadeFrames();
			}
		});
		tile.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent ae) {
				WindowMenu.this.desktop.tileFrames();
			}
		});
		addMenuListener(new MenuListener() {
			public void menuCanceled(MenuEvent e) {
			}

			public void menuDeselected(MenuEvent e) {
				removeAll();
			}

			public void menuSelected(MenuEvent e) {
				buildChildMenus();
			}
		});
	}

	/* Sets up the children menus depending on the current desktop state */
	private void buildChildMenus() {
		int i;
		ChildMenuItem menu;
		JInternalFrame[] array = desktop.getAllFrames();

		add(cascade);
		add(tile);
		if (array.length > 0)
			addSeparator();
		cascade.setEnabled(array.length > 0);
		tile.setEnabled(array.length > 0);

		for (i = 0; i < array.length; i++) {
			menu = new ChildMenuItem(array[i]);
			menu.setState(i == 0);
			menu.addActionListener(new ActionListener() {
				public void actionPerformed(ActionEvent ae) {
					JInternalFrame frame = ((ChildMenuItem) ae.getSource())
							.getFrame();
					frame.moveToFront();
					try {
						frame.setSelected(true);
					} catch (PropertyVetoException ex) {
						logger.error(ex.toString());
					}
				}
			});
			menu.setIcon(array[i].getFrameIcon());
			add(menu);
		}
	}

	/*
	 * This JCheckBoxMenuItem descendant is used to track the child frame that
	 * corresponds to a give menu.
	 */
	class ChildMenuItem extends JCheckBoxMenuItem {
		private JInternalFrame frame;

		public ChildMenuItem(JInternalFrame frame) {
			super(frame.getTitle());
			this.frame = frame;
		}

		public JInternalFrame getFrame() {
			return frame;
		}
	}
}