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@interface OLEContainerScrollView : UIScrollView - (void)addSubviewToContainer:(UIView *)subview; - (void)removeSubviewFromContainer:(UIView *)subview; @end 

 @implementation OLEContainerScrollView ... - (void)layoutSubviews { [super layoutSubviews]; // Translate the container view's content offset to contentView bounds. // This keeps the contentview always centered on the visible portion of the container view's // full content size, and avoids the need to make the contentView large enough to fit the // container view's full content size. self.contentView.frame = self.bounds; self.contentView.bounds = (CGRect){ self.contentOffset, self.contentView.bounds.size }; // The logical vertical offset where the current subview (while iterating over all subviews) // must be positioned. Subviews are positioned below each other, in the order they were added // to the container. For scroll views, we reserve their entire contentSize.height as vertical // space. For non-scroll views, we reserve their current frame.size.height as vertical space. CGFloat yOffsetOfCurrentSubview = 0.0; for (UIView *subview in self.contentView.subviews) { if ([subview isKindOfClass:[UIScrollView class]]) { UIScrollView *scrollView = (UIScrollView *)subview; CGRect frame = scrollView.frame; CGPoint contentOffset = scrollView.contentOffset; // Translate the logical offset into the sub-scrollview's real content offset and frame size. // Methodology: // (1) As long as the sub-scrollview has not yet reached the top of the screen, set its scroll position // to 0.0 and position it just like a normal view. Its content scrolls naturally as the container // scroll view scrolls. if (self.contentOffset.y < yOffsetOfCurrentSubview) { contentOffset.y = 0.0; frame.origin.y = yOffsetOfCurrentSubview; } // (2) If the user has scrolled far enough down so that the sub-scrollview reaches the top of the // screen, position its frame at 0.0 and start adjusting the sub-scrollview's content offset to // scroll its content. else { contentOffset.y = self.contentOffset.y - yOffsetOfCurrentSubview; frame.origin.y = self.contentOffset.y; } // (3) The sub-scrollview's frame should never extend beyond the bottom of the screen, even if its // content height is potentially much greater. When the user has scrolled so far that the remaining // content height is smaller than the height of the screen, adjust the frame height accordingly. CGFloat remainingBoundsHeight = fmax(CGRectGetMaxY(self.bounds) - CGRectGetMinY(frame), 0.0); CGFloat remainingContentHeight = fmax(scrollView.contentSize.height - contentOffset.y, 0.0); frame.size.height = fmin(remainingBoundsHeight, remainingContentHeight); frame.size.width = self.contentView.bounds.size.width; scrollView.frame = frame; scrollView.contentOffset = contentOffset; yOffsetOfCurrentSubview += scrollView.contentSize.height; } else { // Normal views are simply positioned at the current offset CGRect frame = subview.frame; frame.origin.y = yOffsetOfCurrentSubview; frame.size.width = self.contentView.bounds.size.width; subview.frame = frame; yOffsetOfCurrentSubview += frame.size.height; } } self.contentSize = CGSizeMake(self.bounds.size.width, fmax(yOffsetOfCurrentSubview, self.bounds.size.height)); } @end