Move two ScrollView in different ViewControllers - ios

Question

I have the following problem, I am building a school schedule and I have 2 viewControllers with scrollView in each. In the viewController "Bloques" I have a containerView at the side of the list (The list is inside a scrollView), which will contain the "Dias" viewController, the idea is that when I switch from one day to another using paging in "Dias", don't move the list of bloques. The problem is that the list is too long, so I use the scrollView in both viewController, which have the same number of frames, then when I scroll on the Y axis for example "Bloques", I want it to also perform Scroll in the "Dias" scrollView. In another project I did something similar, but within the same viewController, which did not cause me major complications, but being in different viewControllers generates the following error:
Fatal error: unexpectedly found nil while unwrapping an Optional value:
Error:
Structure of viewControllers:
BLOQUES
#IBOutlet weak var bloquesScrollView: UIScrollView!
override public func viewDidLoad() {
super.viewDidLoad()
bloquesScrollView.delegate = self
}
func scrollViewDidScroll(_ scrollView: UIScrollView) {
if scrollView.restorationIdentifier == "bloques" {
let ejey = bloquesScrollView.contentOffset.y
let pruebaController: prueba = prueba()
pruebaController.mover(y: Int(ejey))
}
}
DIAS
#IBOutlet weak var diasScrollView: UIScrollView!
func mover(y: Int?) {
print("casi \(y)")
diasScrollView.setContentOffset(CGPoint(x: 0, y: y!), animated: false)
}
override func viewDidLoad() {
super.viewDidLoad()
diasScrollView.delegate = self
}
Correcting the question, I look for a method in which different UIViewController (Monday, Tuestaday, etc) which contain ScrollView corresponding to blocks in the UIViewController "Bloques", give the movement signal to the ScrollView of "Blocks" if they too move or vice versa.
It should be mentioned that Monday, Tuesday, etc. Are contained in a Container View in "Bloques".
I understand that Container View controller manages a view just like any other UIViewController subclass, in this case, the image in the middle is the UIViewController of the Container View, which will run Monday, Tuesday, etc. Previously what I realized was a list of "Bloques" was inside each UIViewController (Monday, Tuesday, etc.), so it was easier to do it, but the view is strange, since the listing should be static and not be move and appear again on the next page (From Monday to Tuesday for example). I do not know if there is an easier method than the one I am proposing.
New Situation

Answer 1

EDIT
The problem is that in your first code let pruebaController: prueba = prueba() creates a whole new prueba instance. That is not the same prueba that has a scrollView, so its scrollView is nil and you crash when you try to use it.
Please try this code..
BLOQUES
#IBOutlet weak var bloquesScrollView: UIScrollView!
override public func viewDidLoad() {
super.viewDidLoad()
bloquesScrollView.delegate = self
}
func scrollViewDidScroll(_ scrollView: UIScrollView) {
if scrollView.restorationIdentifier == "bloques" {
let ejey = bloquesScrollView.contentOffset.y
// try this code....
let vc = UIStoryboard(name: '<Here Your storyboard name (default : "main">', bundle: nil)
.instantiateViewController(withIdentifier: '<Here Your DIAS Identifier>') as! prueba
vc.mover(y: Int(ejey))
}
}