Generally resurrecting is frowned upon but this is a sticky so it doesn't really matter.
From the tutorial :
It's going to be difficult to explain eventdata clearer than that.
Without seeing what you have done in your program it's difficult to say what is different or why it is not working.
How about adding a post to the MaxGUI forum with some sample code and asking why eventdata isn't returning what you think it should?
From the tutorial :
When a user click one of the tabs, a EVENT_GADGETACTION event will be triggered by MaxGUI. We then need to check the event's eventdata by using the EventData() function. When the user clicks the first tab, EvenData() returns zero and when the user clicks the 2nd tab, EventData() returns 1.
It's going to be difficult to explain eventdata clearer than that.
Without seeing what you have done in your program it's difficult to say what is different or why it is not working.
How about adding a post to the MaxGUI forum with some sample code and asking why eventdata isn't returning what you think it should?