enhanceddialog.java

用java 编写的源码开放的文本编辑器。有很多有用的特性

/*
 * EnhancedDialog.java - Handles OK/Cancel for you
 * Copyright (C) 1998, 1999, 2001 Slava Pestov
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or any later version.
 *
 * 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.
 */

package org.gjt.sp.jedit.gui;

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

/**
 * A dialog box that handles window closing, the ENTER key and the ESCAPE
 * key for you. All you have to do is implement ok() (called when
 * Enter is pressed) and cancel() (called when Escape is pressed, or window
 * is closed).
 * @author Slava Pestov
 * @version $Id: EnhancedDialog.java,v 1.2 2002/10/07 21:13:19 spestov Exp $
 */
public abstract class EnhancedDialog extends JDialog
{
	public EnhancedDialog(Frame parent, String title, boolean modal)
	{
		super(parent,title,modal);
		_init();
	}
	
	public EnhancedDialog(Dialog parent, String title, boolean modal)
	{
		super(parent,title,modal);
		_init();
	}

	public abstract void ok();
	public abstract void cancel();

	//{{{ Private members
	
	private void _init() {
		((Container)getLayeredPane()).addContainerListener(
			new ContainerHandler());
		getContentPane().addContainerListener(new ContainerHandler());

		keyHandler = new KeyHandler();
		addKeyListener(keyHandler);
		addWindowListener(new WindowHandler());

		setDefaultCloseOperation(DO_NOTHING_ON_CLOSE);
	}

	//}}}
	
	// protected members
	protected KeyHandler keyHandler;

	// Recursively adds our key listener to sub-components
	class ContainerHandler extends ContainerAdapter
	{
		public void componentAdded(ContainerEvent evt)
		{
			componentAdded(evt.getChild());
		}

		public void componentRemoved(ContainerEvent evt)
		{
			componentRemoved(evt.getChild());
		}

		private void componentAdded(Component comp)
		{
			comp.addKeyListener(keyHandler);
			if(comp instanceof Container)
			{
				Container cont = (Container)comp;
				cont.addContainerListener(this);
				Component[] comps = cont.getComponents();
				for(int i = 0; i < comps.length; i++)
				{
					componentAdded(comps[i]);
				}
			}
		}

		private void componentRemoved(Component comp)
		{
			comp.removeKeyListener(keyHandler);
			if(comp instanceof Container)
			{
				Container cont = (Container)comp;
				cont.removeContainerListener(this);
				Component[] comps = cont.getComponents();
				for(int i = 0; i < comps.length; i++)
				{
					componentRemoved(comps[i]);
				}
			}
		}
	}

	class KeyHandler extends KeyAdapter
	{
		public void keyPressed(KeyEvent evt)
		{
			if(evt.isConsumed())
				return;

			if(evt.getKeyCode() == KeyEvent.VK_ENTER)
			{
				// crusty workaround
				Component comp = getFocusOwner();
				while(comp != null)
				{
					if(comp instanceof JComboBox)
					{
						JComboBox combo = (JComboBox)comp;
						if(combo.isEditable())
						{
							Object selected = combo.getEditor().getItem();
							if(selected != null)
								combo.setSelectedItem(selected);
						}
						break;
					}

					comp = comp.getParent();
				}

				ok();
				evt.consume();
			}
			else if(evt.getKeyCode() == KeyEvent.VK_ESCAPE)
			{
				cancel();
				evt.consume();
			}
		}
	}

	class WindowHandler extends WindowAdapter
	{
		public void windowClosing(WindowEvent evt)
		{
			cancel();
		}
	}
}