circular scrollview through NSTimer?

I have created sample circular UIScrollview.it works fine.but i want to scroll through NSTimer automatically.when I开发者_运维知识库 implemented , after reaching last item in scrolliview, it did not repeat like looping.any help please?

in that animate method write below condition i think it will work

scrollView.contentOffset.x=(scrollView.contentOffset.x>=scrollView.contentSize.width-scrollView.frame.size.width)?0:scrollView.contentOffset.x+5;