I actually work on a app in Swift.
I have my main ViewController with a ScrollView only.
In my swift file i add 3 view (3 subview controller) into the ScrollView in order to have a special navigation (horizontal navigation like a View Pager).

The problem is that each view has his swift file and therefore i don't find the solution to communicate with the ScrollView of the main ViewController from a subview.
For example a SubViewController (one of the three) have button on it.
And i would put a listener on this button and On click move the position of the screen in the ScrollView (which is on the main view controller), thanks to the method setContentOffset of the scrollview.
 
     
     
    