Apex 3.2, How to use an onchange event with Popup Key LOV - it ignores me.

Question

Hoping there is a simple solution to this.
Using Apex 3.2 with a simple form with a few fields. When the user selects a value from a Popup Key LOV, I want to fire a javascript onchange event and alter another field on the form.
Seems simple enough, except that I can't figure out how to make the PopUp respond to onchange events. The default template seems to ignore javascript entered into the attribute fields that work in other form fields. I know this is simple do to for a select list - it works as expected there. A select list is not a good option because of the huge number of possible returned values.
Even tried a different approach...to register the onchange event using the "addLoadEvent" with this code (this also does not work):
function setThisUp() {
var x = document.getElementById('P105_CTR_ID');
x.onClick = popupLovChanged;
function popupLovChanged() {
alert('OMG IT WORKS!');
addLoadEvent(setThisUp);
If any of you have some advice on how to make onchange work, it would be greatly appreciated.
Thanks in advance
-Rich

Answer 1

For those still looking for a solution.
I found that you can overwrite the default javascript function passback(x) in the popup lov's template, just add your function in the After Field Text field of the template
e.g.
<script> function passBack(x) {
opener.document.getElementById('P2_PROGRAMME').value = x;
opener.document.getElementById('P2_PROGRAMME').focus();
close();
} </script>
this is going to populate the 'P2_PROGRAMME' field with selected value, and focus on it.
in your case, just add the codes you want to run into the passback function.
hope this helps