propertyChange

I trying to run script on a propertychange but only when the value has changed. but it seems that the value it getting updated with the same value every so seconds.

I have a list that when someone selects an item in that list it writes that vale in a input box. my script is on the input box when the input box value changes it fires but nothing is changing the current selected value in the listbox and the script keeps firing. I assume it it is contently polling the listbox. So my thought was to put the following in:

if event.propertyName == “value” and event.newValue <> event.oldValue:
run script here

but this does not work how i thought it would. Any ideas? I put a messagebox on oldValue and it seems like it changes from ex: 123123 to -1 then back to 123123.

I see, what if you try the table component with one column instead of the list?