iOS 11 Swift 4 iPhone X Safe Area Support of full screen ScrollView

Question

I currently have my layout design setup as a fullscreen scrollview on one view controller in which I add other view controllers as sub views to create a paged effect. On normal iphone screens it works beautifully. However when running on iPhone X, things seem to appear off centered, and I can page in multiple times in one page.

Here is my code for setup of the scrollview

self.scrollView.contentSize = CGSize(width: self.view.frame.width, height: self.view.frame.size.height * 3)
        if #available(iOS 11.0, *) {
            self.scrollView.contentInsetAdjustmentBehavior = .never
        } else {
            // Fallback on earlier versions
        }


        let V1 = self.storyboard?.instantiateViewController(withIdentifier: "S1") as! UINavigationController!
        self.addChildViewController(V1!)
        self.scrollView.addSubview(V1!.view)
        V1?.didMove(toParentViewController: self)
        V1?.view.frame = scrollView.bounds
        myViewsArray.append(V1!)

        let V2 = self.storyboard?.instantiateViewController(withIdentifier: "S2") as UIViewController!
        self.addChildViewController(V2!)
        self.scrollView.addSubview(V2!.view)
        V2?.didMove(toParentViewController: self)
        V2?.view.frame = scrollView.bounds
        myViewsArray.append(V2!)

        var V1Frame: CGRect = V1!.view.frame
        V1Frame.origin.y = 2*self.view.frame.height
        V1?.view.frame = V1Frame

        var V2Frame: CGRect = V2!.view.frame
        V2Frame.origin.y = (self.view.frame.height)
        V2?.view.frame = V2Frame

        V2!.view.alpha = 1

I have safe area on in story board.

Answer 1

You can do this using safe area layout guide and get more info using the link:

https://medium.com/rosberryapps/ios-safe-area-ca10e919526f

You can also do this without safe area: I have prepared a demo for you and in this demo, we have three view controllers added on scroll view and scroll view is added on another view controller(ContainerViewController)

ContainerViewController:

import UIKit

class ContainerViewController: UIViewController, UIScrollViewDelegate {

    @IBOutlet weak var scrollView: UIScrollView!

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.
        let V1 = self.storyboard?.instantiateViewController(withIdentifier: "first")
        self.addChildViewController(V1!)
        self.scrollView.addSubview(V1!.view)
        V1?.didMove(toParentViewController: self)
        V1?.view.frame = scrollView.bounds

        let V2 = self.storyboard?.instantiateViewController(withIdentifier: "second")
        self.addChildViewController(V2!)
        self.scrollView.addSubview(V2!.view)
        V2?.didMove(toParentViewController: self)
        V2?.view.frame = scrollView.bounds

        let V3 = self.storyboard?.instantiateViewController(withIdentifier: "third")
        self.addChildViewController(V3!)
        self.scrollView.addSubview(V3!.view)
        V3?.didMove(toParentViewController: self)
        V3?.view.frame = scrollView.bounds

        var V1Frame: CGRect = V1!.view.frame
        V1Frame.origin.y = 0
        V1?.view.frame = V1Frame

        var V2Frame: CGRect = V2!.view.frame
        V2Frame.origin.y = (self.view.frame.height)
        V2?.view.frame = V2Frame

        var V3Frame: CGRect = V3!.view.frame
        V3Frame.origin.y = (self.view.frame.height)*2
        V3?.view.frame = V3Frame
    }
    override func viewDidLayoutSubviews() {
        scrollView.contentSize = CGSize(width: UIScreen.main.bounds.width, height: UIScreen.main.bounds.height*3)
    }
}

Note: Remove top and bottom constraint from the safe area and add them from SuperView(for Scroll view, InnerView(FirstVC, SecondVC, ThirdVC))`

You can check all the functionality and constraints of the demo project. Download URL: https://www.dropbox.com/s/4ovfqmrtwt2i8yi/StackOverflow.zip?dl=0

I have tested the demo in iPhoneX and iPhone6 and iPhone8+

Screenshots are below: