import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
import java.awt.*;
import java.awt.event.*;
import java.net.*;
import java.io.*;
/*
* Simple Help Frame based on JFC JEditorPane
* May someday rewrite using JavaHelp API.
*/
public class MyHelp extends JFrame implements HyperlinkListener {
/** The contentpane */
protected Container cp;
/** The editorpane */
JEditorPane help;
/* Construct a Help object. Just construct a JEditorPane
* with a URL, and it does all the help from there.
*/
public MyHelp() {
super("Help Window");
cp = getContentPane();
getAccessibleContext().setAccessibleName("TestEdit Help Window");
getAccessibleContext().setAccessibleDescription("A window for viewing TestEdit HELP, which is somewhat hyperlinked.");
try {
URL url = new URL("file:///"+ System.getProperty("user.dir")+
"/help/index.html");
// Only create the window once.
if (help == null) {
// System.out.println("Creat-ing help window for " + url);
help = new JEditorPane(url);
// System.out.println("Done!");
help.setEditable(false);
help.addHyperlinkListener(this);
JScrollPane scroller = new JScrollPane();
scroller.setBorder(BorderFactory.createTitledBorder("TestEdit Help"));
scroller.getViewport().add(help);
cp.add(BorderLayout.CENTER, scroller);
addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {
MyHelp.this.setVisible(false);
MyHelp.this.dispose();
}
});
setSize(500,400);
} else {
System.out.println("Re-using help window!");
}
} catch (MalformedURLException e) {
System.out.println("Malformed URL: " + e);
} catch (IOException e) {
System.out.println("IOException: " + e);
}
}
/**
* Notification of a change relative to a hyperlink.
* From: java.swing.event.HyperlinkListener
*/
public void hyperlinkUpdate(HyperlinkEvent e) {
if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED) {
URL target = e.getURL();
// System.out.println("linkto: " + target);
// Get the help panel's cursor and the wait cursor
Cursor oldCursor = help.getCursor();
Cursor waitCursor = Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR);
help.setCursor(waitCursor);
// Now arrange for the page to get loaded asynchronously,
// and the cursor to be set back to what it was.
SwingUtilities.invokeLater(new PageLoader(target, oldCursor));
}
}
/**
* Inner class that loads a URL synchronously into the help panel.
* Loads it later than the request so that a cursor change
* can be done at the very end.
* @author BORROWED FROM SUN'S SWING DEMO, UNTIL JAVAHELP AVAILABLE
*/
class PageLoader implements Runnable {
URL url;
Cursor cursor;
PageLoader(URL u, Cursor c) {
url = u;
cursor = c;
}
public void run() {
// System.out.println("PageLoader: u=" + url);
if (url == null) {
// restore the original cursor
help.setCursor(cursor);
// PENDING(prinz) remove this hack when
// automatic validation is activated.
Container parent = help.getParent();
parent.repaint();
} else {
Document doc = help.getDocument();
try {
help.setPage(url);
} catch (Exception ioe) {
help.setDocument(doc);
getToolkit().beep();
} finally {
// schedule the cursor to revert after
// the paint has happended.
url = null;
SwingUtilities.invokeLater(this);
}
}
}
}
/** Test case */
public static void main(String a[]) {
new MyHelp().setVisible(true);
}
}
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