Abstract Dialog Class

Here is the code from a class that I have used for years. This class extends JDialog in a way that adding components to it is very painless, since it uses GridBagLayout. I hope to soon comment it better and add an example, but for now you will have to look at the code to see what is going on.

package org.markwebb.gui;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.BorderFactory;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.TitledBorder;

/**
 * This is an abstract class which takes many of the pains out of
 * GridBagLayout.  The Dialog is set to modal.
 * 
 * @author Mark Webb 
 *
 */
public abstract class AbstractDialog extends JDialog implements ActionListener {

	protected static final String ACCEPT = "Accept";
	protected static final String CANCEL = "Cancel";
	protected static final String CLOSE = "Close";
	
	protected JPanel mainPanel;
	
	protected GridBagConstraints c;
	private int row, col;
	
	public AbstractDialog( JFrame parent, String title, String borderTitle ){
		super( parent, title, true );
		
		setDefaultCloseOperation( JDialog.DISPOSE_ON_CLOSE );
		
		c = new GridBagConstraints();
		c.fill = GridBagConstraints.BOTH;
		c.anchor = GridBagConstraints.WEST;
		c.insets = new Insets(5,5,5,5);
		
		row = 0;
		col = 0;
		
		mainPanel = new JPanel();
		mainPanel.setBorder( BorderFactory.createTitledBorder(BorderFactory.createLineBorder(Color.black, 1),
				borderTitle, TitledBorder.LEFT, TitledBorder.TOP ));
		
		mainPanel.setLayout( new GridBagLayout() );
		add( mainPanel, BorderLayout.CENTER );
		
		JPanel buttons  = new JPanel();
		JButton accept = new JButton( ACCEPT );
		accept.addActionListener( this );
		buttons.add( accept );
		JButton cancel = new JButton( CANCEL );
		cancel.addActionListener( this );
		buttons.add( cancel );
		JButton close = new JButton( CLOSE );
		close.addActionListener( this );
		buttons.add( close );
		
		add( buttons, BorderLayout.SOUTH );
	}

	public void addToRow( JComponent comp, int width ){

		// add the component
		addItem( col, row, width , comp );
		
		// increment the column number
		col++;
	}
	
	public void addToNewRow( JComponent comp, int width ){
		
		// increment the row number
		row++;
		
		// reset the column number
		col = 0;
		
		// add the component
		addItem( col, row, width , comp );
		
		// increment the column number
		col++;
	}
	
	private void addItem( int x, int y, int w, JComponent comp )
	{
		c.gridx = x;
		c.gridy = y;
		c.gridwidth = w;
		mainPanel.add( comp, c );
	}
	
	public void actionPerformed( ActionEvent e ){
		if( e.getActionCommand().equals( ACCEPT )){
			doAccept();
		} else if( e.getActionCommand().equals( CANCEL )){
			doCancel();
		} else if( e.getActionCommand().equals( CLOSE )){
			doClose();
		}
	}
	
	private void doClose(){
		setVisible( false );
	}
	
	protected abstract void doAccept();
	protected abstract void doCancel();
}