How to detect joystick reaching the end ?

https://rive.app/community/forums/support/fsnLLkXUaA62/events-in-joystick-driven-timeline/ftMtGkStQsFe
Following this thread, I'm trying to detect when a joystick driven timeline reaches the end to trigger an isDone event but so far I have not managed to find a way to do this. Would someone have an idea on how to do this ?
Thanks for the help