UIView on top of a Container View

Question

Is it possible to display an UIView on top of a container View?

I want to add a view with a few opacity background to still see my container View. But everything i tried made either my containerView disappear completely or on top of my View. I tried via Storyboard and code.

I'm sure I'm missing something.

Answer 1

just add your view to the view property of your container controller's container

simple:

let viewYouWantToAddSubviewTo = parent?.view

detail:

import UIKit

class CustomNavigationViewController: UINavigationController {

    override func viewDidLoad() {
        super.viewDidLoad()
        setupViews()
    }

    func setupViews() {
        let layout = UICollectionViewFlowLayout()
        let rootVC = HomeCollectionViewController(collectionViewLayout: layout)
        viewControllers = [rootVC]
        let v = UIView()
        v.backgroundColor = UIColor.blue
        v.layer.opacity = 0.4
        v.translatesAutoresizingMaskIntoConstraints = false

        // add your view to this view of the controller's container
        let vv = (parent?.view)! 

        vv.addSubview(v)

        // constraints for v
        v.leftAnchor.constraint(equalTo: vv.leftAnchor).isActive = true
        v.rightAnchor.constraint(equalTo: vv.rightAnchor).isActive = true
        v.topAnchor.constraint(equalTo: vv.topAnchor).isActive = true
        v.bottomAnchor.constraint(equalTo: vv.bottomAnchor).isActive = true
    }
}

result: