How to Insert and call custom Code in CaptivateMainTimeine.as?

Question

I have been trying to get my head around this, using various blog postings by Jim Leichliter as my guide. However, so far I have been defeated.
This is what I attempted (in Captivate 5):
1) I inserted the following code into CaptivateMaintimeline.as, just above the private function AddEICallbacks() section:
public function helloWorld(){
  alert('hello world');
2) Just above the EICallbacksAdded = true; line, I inserted
ExternalInterface.addCallback("helloWorld", helloWorld);
3) I created a one-slide Captivate 5 presentation with a button whose "On Success" action is set to "Execute Javascript".
4) In the "Execute Javascript" Script_Window, I entered this code:
Captivate.helloWorld();
5) I published the presentation and viewed it in Chrome, Firefox and IE 9, which all reported an error, as follows:
(Chrome) "Uncaught TypeError: Object #<HTMLEmbedElement> has no method 'helloWorld'"
(Firefox) "Captivate is not defined"
(IE 9) "Object doesn't support property or method 'helloWorld'"
6) I changed the script window code to
document.Captivate.helloWorld();
and published and viewded in Chrome in Firefox, with the following results:
(Chrome) "Uncaught TypeError: Object #<HTMLEmbedElement> has no method 'helloWorld'"
(Firefox) "document.Captivate.helloWorld is not a function"
7) I also tried
document.getElementById('Captivate').helloWorld();
and published and viewed in IE 9, getting the same error as previously,
"Object doesn't support property or method 'helloWorld'"
Can anyone see what I am missing here?

Answer 1

Thanks, Jim. Your example got my "proof-of-concept" working.
I had jumped to the unwarranted conclusion that core JavaScript functions were directly accessible from ActionScript. Investigating further as a result of your comment, I discovered the ExternalInterface.call technique for using JavaScript functions in ActionScript when I actually need to. (Ref. http://codingrecipes.com/calling-a-javascript-function-from-actionscript-3-flash and http://www.actionscript.org/resources/articles/745/1/JavaScript-and-VBScript-Injection-in- ActionScript-3/).
Some background: I wrote my first program in Fortran in 1966 and having been coding ever since. For most of the last two decades, most of what I have written has been in the VB, VB.NET, and ASP.NET worlds, but now I am going through a steep Captivate + ActionScript + JavaScript learning curve as I use Captivate to create course materials for the learning institution where I work. It would be simpler if the materials were only ever going to be run from our web server, but as well as on-campus students we have distance students across the country. We provide the distance students with a computer preloaded with the materials, but not all students have an Internet connection, so I am trying to create materials that can be run stand-alone from the computer's file system or served from a web server with equal facility.
Add in the complication that there are many keyboard shortcuts that Internet Explorer doesn't pass through to Flash, therefore hobbling some of the training and assessment simulations, and you can see that the Captivate presentations have to have sufficient logic built in to detect the environment in which they are running and adjust accordingly. As I will be calling upon this logic over and over again, I would like it to be in one place and access it by a simple JavaScript call from the opening slide of every presentation, thus populating a number of Captivate variables with the environmental information which can then be used to branch the presentation to alternative slides wherever necessary. Therefore, embedding the logic into a customized version of CaptivateMainTimeLine.as seemed the way to go, but if anyone can suggest a better strategy, I am open to all ideas!
Trevor