While I\'ve used UIScrollView successfully in the past by manipulating it programmatically, I\'m having trouble getting it to work by setting it up exclusively
I find out a more convenient way.
1: Scale the size of the scroll view to contain all the ui inside it.
2: Add a iboutlet of the scroll view.
3: In viewDidLoad, save the frame.size of the scroll view.
(e.g. _scrollSize = _scrollView.frame.size;)
4: In viewWillAppear, set the contentSize by the CGSize you saved before.
(e.g. _scrollView.contentSize = _scrollSize;)
5: Done~