Question

I’m working on a project where we’re using a Java applet for part of the UI (a map, specifically), but building the rest of the UI around the applet in HTML/JavaScript, communicating with the applet through LiveConnect/NPAPI. A little bizarre, I know, but let’s presume that setup is not under discussion. I started out planning on using jQuery as my JavaScript framework, but I’ve run into two issues.

Issue the first:

Selecting the applet doesn’t provide access to the applet’s methods.

Java:

public class MyApplet extends JApplet {   // ...   public String foo() { return 'foo!'; } } 

JavaScript:

var applet = $('#applet-id'); alert(applet.foo()); 

Running the above JavaScript results in

$('#applet-id').foo is not a function

This is in contrast to Prototype, where the analogous code does work:

var applet = $('applet-id'); alert(applet.foo()); 

So…where’d the applet methods go?

Issue the second:

There’s a known problem with jQuery and applets in Firefox 2: http://www.pengoworks.com/workshop/jquery/bug_applet/jquery_applet_bug.htm

It’s a long shot, but does anybody know of a workaround? I suspect this problem isn’t fixable, which will mean switching to Prototype.

Thanks for the help!

Answer 1

For the first issue, how about trying

alert( $('#applet-id')[0].foo() ); 

For the second issue here is a thread with a possible workaround.

Quoting the workaround

// Prevent memory leaks in IE // And  prevent errors on refresh with events  like mouseover in other  browsers // Window isn't included so as not to unbind existing unload events jQuery(window).bind('unload', function() {         jQuery('*').add(document).unbind(); }); 

change that code to:

// Window isn't included so as not to unbind existing unload events jQuery(window).bind('unload', function() {         jQuery('*:not('applet, object')').add(document).unbind(); });