Excuse me for not being clear before.
Thank you for the link. Unfortunately it does not help a bit, since it does not tell me in any way what arguments I can give to a Submit or a Cancel Button. The documentation only includes a text messages telling me that a SubmitButton is used to submit a form. Anyways, I already solved my problem. I was just hoping for some better documentation for future/similar questions.
Thanks again for the feedback :)