UIButton在UIScrollview中设置框架后没有响应

I have a UIScrollView which content is designed with Interface Builder. It has a table with a UIButton below. If the button wasn't moved before, it works (touchesBegan and TouchUpInside get called), but if it was moved using 'button.frame = ' in response of content growth (the table got bigger), it stops responding to any touch.I have a UIScrollView which content is designed