Hello People

I am using af Ares.
I have created a Activity Button, but have some problems controlling the "deactivate" function.
When i press the button i make a Ajax.request and the spinner starts when i press the botton.
But when i am finished (onSuccess) i would like to stop the spinner. When i use
Code:
this.controller.get('button').mojo.deactivate();
I get an exception that i can not see.

I i use the line when the event starts (before request) it works. But that is not the point because i need it to spin ontil i get the request back.
Please help