Relationship between contentSize, contentOffset and animation

UIScrollView's core has 2 properties which manage the visible portions of the scroll view on the screen.

- When we set contentSize

• if the contentOffset is beyond the new contentSize the contentOffset is reset.
• else the contentOffset is not changed. 

If you want to animate the contentOffset in the case when your contentOffset goes beyond contentSize then:

[[UIView animateWithDuration:0.2
                animations:^{

                                   self.contentSize = CGSizeMake(self.scrollViews.count *                      self.bounds.size.width, self.bounds.size.height);

                                     }
                 completion:NULL];