Creo 2 External Automation

Hi all,

I am currently trying to implement functional GUI testing of a PLM System that communicates with Creo Parametric 2 and vice-versa. Since "real" GUI automation in Creo 2 seems almost impossible because the Windows UI Automation Support is disabled, all I'm trying to do is press one Button in Creo. This button is added through a customization (i.e. it's not there in standard Creo), and the triggered action would be to open our PLM system to search for a file that is to be loaded.

JLink seems to be the wrong tool for that (just pressing a button), and I couldn't find any simple way to do so. I thought about using a trail file, but the only viable option to do so seems to be starting Creo with the trail file as a parameter, which would execute it directly after startup. This is not possible because the PLM system and Creo are started together and the PLM System needs to perform a login before Creo can ask it for a file...

TL;DR: I need a way to trigger a button click (or the action itself) from outside of Creo for an already running Creo instance at a time of my chosing. Does anybody have any tips / hints / experiences with that (be it JLink, Trail files, or sth. else)?

Thanks in advance and best wishes,

Jonas