Loading AVPlayer into UIView with Swift 5

AVPlayer+UIView.swift

//
//  BackgroundVideoPlayerViewController.swift
//  DeveloperBelt
//
//  Created by Egzon Pllana on 10/7/19.
//  Copyright © 2019 Native Coders. All rights reserved.
//

import UIKit
import AVFoundation

class BackgroundVideoPlayerViewController: UIViewController {

    // MARK:  - Properties

    @IBOutlet weak var videoView: UIView!

    private var playerItem: AVPlayerItem!
    private var player: AVPlayer!
    let center = NotificationCenter.default

    // Observer should always be set
    var playerObserver: NSKeyValueObservation!

    // MARK: - Delegates

    weak var pageViewController: OnBoardingPageViewController?

    // MARK:  - View Life cycle

    override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.

        // MARK: Hide navigation controller
        self.navigationController?.navigationBar.isHidden = true

        videoAnimationSetup()
    }

    override func viewDidDisappear(_ animated: Bool) {
        super.viewDidDisappear(animated)
        self.player.replaceCurrentItem(with: nil) /* deallocate memory */
        center.removeObserver(NSNotification.Name.AVPlayerItemDidPlayToEndTime)
        playerObserver.invalidate()
    }

    // MARK: - Methods

    // Configure the video animation
    private func videoAnimationSetup() {
        // retrive video from project files, type "mp4"
        let videoURL = Bundle.main.url(forResource: "launch", withExtension: "mp4")
        let asset = AVAsset(url: videoURL!)

        // configure player
        playerItem = AVPlayerItem(asset: asset)
        observePlayer(playerItem)
        player = AVPlayer(playerItem: playerItem)
        let playerLayer = AVPlayerLayer(player: player)

        // add player layer to view layer
        playerLayer.frame = self.videoView.frame
        playerLayer.videoGravity = .resizeAspectFill
        self.videoView.layer.addSublayer(playerLayer)

        // handle video end
        center.addObserver(self, selector: #selector(videoEnded), name: NSNotification.Name.AVPlayerItemDidPlayToEndTime, object: playerItem)
    }

    // Observes when the player item is ready to play and handles automatic play back
    private func observePlayer(_ playerItem: AVPlayerItem) {
        playerObserver = playerItem.observe(\AVPlayerItem.status) { [weak self] (playerItem, _) in
            if playerItem.status == .readyToPlay {
                self?.player.play()
            }
        }
    }

    @objc private func videoEnded() {
        playerItem.seek(to: CMTime.zero) { (finished) in
            if finished {
                OperationQueue.main.addOperation { [weak self] in
                    self?.player.play()
                }
            }
        }
    }
}