HelpInfoDialog.java

package bsearch.app;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.WindowConstants;

public class HelpInfoDialog extends javax.swing.JDialog {

	private static final long serialVersionUID = 1L;
	private JTextPane jTextPaneContent;
	private JScrollPane jScrollPane1;
	private JButton jButtonOk;

	public HelpInfoDialog(JFrame frame, String title, String htmlText) {
		super(frame, title);

		jTextPaneContent = new JTextPane();
		jTextPaneContent.setContentType("text/html");
		jTextPaneContent.setText(htmlText);
		jTextPaneContent.setEditable(false);
		jTextPaneContent.setMaximumSize(new java.awt.Dimension(620,600));

		jScrollPane1 = new JScrollPane(jTextPaneContent);
		getContentPane().add(jScrollPane1, BorderLayout.CENTER);
		jScrollPane1.setMaximumSize(new java.awt.Dimension(620,600));

		jButtonOk = new JButton("OK");
		getContentPane().add(jButtonOk, BorderLayout.SOUTH);
		jButtonOk.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				setVisible(false);
			}					
		});
		// make sure the OK button always gets focus, so it's easy to close the help dialog.
		this.addWindowFocusListener(new java.awt.event.WindowAdapter() {
		    @Override
			public void windowGainedFocus(java.awt.event.WindowEvent e) {
		        jButtonOk.requestFocusInWindow();
		    }
		});

		 
		this.pack();  // size the window based on the textpane's contents
		// but long lines of text can cause the size of the window to be ridiculous, so we fix it
		if (this.getWidth() > 640)
		{
			this.setSize(640, Math.min(this.getHeight() * 3 / 2, 440));
		}
		if (this.getHeight() > 440)
		{
			this.setSize(Math.min(this.getWidth() * 3 / 2, 640), 440);
		}
		this.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
	}
	
	public static void showHelp(JFrame parent, String title, String htmlText)
	{
		HelpInfoDialog hdialog = new HelpInfoDialog(parent, title, htmlText);
		hdialog.setLocationRelativeTo(null);
		hdialog.setVisible(true);		
	}

	
}