[framework static plugin] jquery functions work only if I load the plug-in file itself, not in parent page, why?

Hello all,
I'm having really a bad time with framework plug-ins.
This is because I have not undertood the mechanism completely.

I created 1 page as test containing one plug-in.

Page 1 contains a form (only one select field).
Page 2(plug-in) contains another select field. Page 2 contains a recordset that filters the select values).

Now I need to show an alert (javascript) when the page2 select change.

The alert is shown when I run the page2 alone on my local server.
But the alert is not shown when the page2 select is called by page1.

I tried to move the alert message to the page1, but nothing changes.
What is the logic?
Have I to add all logic to the plug-in page or to the main page?
I cannot understand how framework plug-in work.

TIA
tony

Since the select list is re-created, the onchange event has to be re-binded as well. If you attached both pages then I could give code examples of how to do it.

The easier method might be to use the onchange property in the html instead of the .change() jquery method to bind the event so that you wouldn't have to re-bind it after every load, but both are actually pretty easy to accomplish but difficult to explain out of context.