Run a custom action on every tap?

I'm trying to make a timeout popup where after x seconds of inactivity, user is prompted if they are still there (this is a public kiosk).

I've found this widget however I couldn't make it work. So my next idea is to create a simple custom action that resets an integer each time it's run. That integer then would be tied to timer countdown, which will trigger the modal popup if it hits zero.

By adding this custom action to reset the integer to every tap, I could simulate a way to look for user inactivity. However I don't know if this is possible and clearly going through every action & adding it manually is not feasible.

Would this (or any other timeout feature) be possible to implement through FlutterFlow?