There's a disconnect somewhere between your posts. If the layout XML file you posted is indeed your main XML layout, then adding button to it can't possibly result in multiple double buttons appearing in the layout, because the list view does not use that layout. From your code it's clear that it uses a layout called "list_mobile". So - what happened when you added two buttons to your main XML layout file?
Also, my first name is "Ulf". If you want to address me by my last name then the polite way to do so is to say "Mr. Dittmer". First name's fine, though, like you did with Steve. I already pointed that out here
; please do so from now on.