How to add a NSVisualEffectView to a View in Cocoa

MyViewController.swift

import Cocoa

class MyViewController: NSViewController {
	
	var visualEffect: NSVisualEffectView!

	override func loadView() {
		super.loadView()

		visualEffect = NSVisualEffectView()
		visualEffect.translatesAutoresizingMaskIntoConstraints = false
		visualEffect.material = .dark
		visualEffect.state = .active
		view.addSubview(visualEffect)

		visualEffect.leadingAnchor.constraint(equalTo: view.leadingAnchor).isActive = true
		visualEffect.trailingAnchor.constraint(equalTo: view.trailingAnchor).isActive = true
		visualEffect.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
		visualEffect.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
	}
}