Service SelectedRowsChanged event not triggering

I'm using a gridadvanced widget populated by a service that returns an infotable, this works fine.

After data is loaded into the grid, I make a popup appear when the user double clicks a row in the grid, passing the service's SelectedRows as a parameter to this popup.

My grid is currently set to Single row selection.

However, the SelectedRows of the service mentioned above never changes, and its SelectedRowsChanged event is never triggered.

Using Thingworx 8.5.4