Category: Javascript

A cross-browser keypress detection javascript

Posted on March 30, 2007 by ellen

We have learning modules that have a lot of pages, and it occurred to me it would be easier on people’s hands if they could simply use the right and left arrow keys to navigate through the module.

After a day of great frustration, I realized that it’s nearly hopeless. Not only do all the browsers report different keycodes for the right and left arrow keys, but Firefox and Safari report both of them as “0” which makes it impossible to distinguish between them.

CSS expression crashes IE6

Posted on March 26, 2007 by ellen

Since IE 6 does not have a “min-width” ccss attribute, I sometimes emulate it, using CSS expressions. For example:

width:expression(document.body.clientWidth

Limiting number of tries on Perception Quizzes under SCORM control

Posted on January 30, 2007 by ellen

When Questionmark Perception is launched from an LMS using SCORM, Perception’s built-in user management system can’t be used. Perception receives user data from the LMS, and although it stores that data with the results of the quizzes, it can’t use the data for purposes of scheduling and limiting access to quizzes.

Unfortunately, our LMS, SumTotal 6.5, does not have a good way to limit attempts on a learning activity either. There is a rather inflexible option: If you set any learning activity to “allow access upon completion,” after the activity has been completed once, the user will only be able to launch the activity for purposes of browsing, but never take it again for credit. In other words, the user can not enroll again.

This isn’t always the best solution. For example, we wanted to allow two or three tries, depending on the quiz, and we never allow users to browse old quizzes.

Various solutions to the IE Active X issue

Posted on October 8, 2006 by ellen

For your convenience, all in one place, here is a list of sites that offer solutions to the new Internet Explorer ActiveX behavior. Includes links to Microsoft, Apple, Real Networks and Adobe pages on the

onChange=”document.form.submit()” doesn’t work

Posted on October 8, 2006 by ellen

Have you ever used the onChange event to submit a form? onChange=”document.form1.submit();” If you are creating a form that submits as soon as a change is made to any selection, make sure you remove the

GoLive’s Javascript IDE

Posted on August 19, 2006 by ellen

Although I don’t use Adobe GoLive much for day-to-day work, it has certain features that are hard to find anywhere else. One of them is a rather impressive Javascript authoring environment. It gives contextual hints,

Minimizing Flash of White on page load

Posted on August 11, 2006 by ellen

While testing a javascript-heavy frameset-based learning module, users complained bitterly about the white frameset background flashing at them before each page loaded, particularly in IE. A related issue was that graphics were not preloading properly

Make any web-based Powerpoint presentation scorm compatible

Posted on May 13, 2006 by ellen

It’s easy to export Powerpoint presentations to the web, but they aren’t automatically scorm compatible. To add simple scorm capability to your web-export, do the following:

This will add a button that will allow the user to mark the sco complete.

1. Add this to the head section of outline.htm or the final slide.
 <script type=”text/javascript” language=”javascript” name=”mm_scormRTI” > <!– Inserted by: // SCORM Runtime Wrapper // version 1.2.6 09/09/02 // Copyright 2000, 2001, 2002 Macromedia, Inc. All rights reserved. // —————————————————- // define global var as handle to API object var mm_adl_API = null; // mm_getAPI, which calls findAPI as needed function mm_getAPI() { var myAPI = null; var tries = 0, triesMax = 500; while (tries < triesMax && myAPI == null) { window.status = ‘Looking for API object ‘ + tries + ‘/’ + triesMax; myAPI = findAPI(window); if (myAPI == null && typeof(window.parent) != ‘undefined’) myAPI = findAPI(window.parent) if (myAPI == null && typeof(window.top) != ‘undefined’) myAPI = findAPI(window.top); if (myAPI == null && typeof(window.opener) != ‘undefined’) if (window.opener != null && !window.opener.closed) myAPI = findAPI(window.opener); tries++; } if (myAPI == null) { window.status = ‘API not found’; alert(‘JavaScript Warning: API object not found in window or opener. (‘ + tries + ‘)’); } else { mm_adl_API = myAPI; window.status = ‘API found’; } } // returns LMS API object (or null if not found) function findAPI(win) { // look in this window if (typeof(win) != ‘undefined’ ? typeof(win.API) != ‘undefined’ : false) { if (win.API != null ) return win.API; } // look in this window’s frameset kin (except opener) if (win.frames.length > 0) for (var i = 0 ; i < win.frames.length ; i++); { if (typeof(win.frames[i]) != ‘undefined’ ? typeof(win.frames[i].API) != ‘undefined’ : false) { if (win.frames[i].API != null) return win.frames[i].API; } } return null; } // call LMSInitialize() function mm_adlOnload() { if (mm_adl_API != null) { mm_adl_API.LMSInitialize(“”); // set status mm_adl_API.LMSSetValue(“cmi.core.lesson_status”, “incomplete”); } } // call LMSFinish() function mm_adlOnunload() { if (mm_adl_API != null) { // set status mm_adl_API.LMSSetValue(“cmi.core.lesson_status”, “completed”); mm_adl_API.LMSCommit(“”); mm_adl_API.LMSFinish(“”); } } // get the API mm_getAPI(); // –> </script>

Debugging and troubleshooting HTML and javascript

Posted on May 11, 2006 by ellen

Firefox, the web developer’s debugging tool of choice

The best browser to use to check javascript errors is Firefox, hands down. Other browsers have some error reporting, but none give you anywhere near the detailed information as Firebug, an addon to Firefox. The extensions available allow you to snoop into every aspect of your page, and into the communication between page and server.

You will need to get several Firefox extensions:

Firebug
Firebug is the one extension I can’t live without. It shows errors in javascript, css, allows you to inspect the HTML source, computed style, events, etc.

Why doesn’t ‘this.childNode’ work?

Posted on April 22, 2006 by ellen

‘this.childNode‘ not working? If you are trying to get a javascript function to work using this.childNode.foo and it’s not working, it’s because the syntax is wrong. Try this.firstChild.foo instead! Guessing at the correct DOM element