如何从自定义视图过渡到AVPlayerViewController？

Question

I have a custom view:

class MediaPlayerView: UIView {

    var mediaURL: URL? {
        didSet {
            determineMediaType()
        }
    }
    let videoExtensions = ["mov"]

    override init (frame : CGRect) {
        super.init(frame : frame)
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
    }

    func determineMediaType() {
        let url = self.mediaURL
        let pathExtention = url?.pathExtension
        if videoExtensions.contains(pathExtention!) {
            print("Movie URL: \(String(describing: url))")
            setupVideo(url: url!)
        } else {
            print("Image URL: \(String(describing: url))")
            setupImage(url: url!)
        }
    }

    func setupVideo(url: URL) {
        let playButton = UIImage(named: "Play Triangle")
        let playButtonView = UIImageView(image: playButton!)
        let singleTap = UITapGestureRecognizer(target: self,  action: #selector(tapDetected))
        playButtonView.addGestureRecognizer(singleTap)
        playButtonView.center = self.center
        playButtonView.frame.size.width  = self.frame.size.width/5
        playButtonView.frame.size.height = self.frame.size.height/5
        playButtonView.autoresizingMask = [.flexibleWidth,.flexibleHeight]
        playButtonView.isUserInteractionEnabled = true
        self.addSubview(playButtonView)
    }

    @objc func tapDetected() {
        print("tap!")

        let player = AVPlayer(url: self.mediaURL!)
        let controller = AVPlayerViewController()
        controller.player = player
        self.window?.rootViewController?.present(controller, animated: true) {
            player.play()
        }
    }

    func setupImage(url: URL) {
        let imageView = UIImageView()
        imageView.frame = self.bounds
        imageView.autoresizingMask = [.flexibleWidth,.flexibleHeight]
        self.addSubview(imageView)
        imageView.kf.setImage(with: url)
    }

}

However when I click the play button, I get the following error:

Warning: Attempt to present <AVPlayerViewController: 0x7fe8b200b000> on <SweatNet.MainTabBarController: 0x7fe8b4816400> whose view is not in the window hierarchy!

It comes on this line: self.window?.rootViewController?.present. I think It is getting confused by me calling the rootViewController (which seems to be SweatNet.MainTabBarController). I want to it to call SweatNet.TagViewController. This is the one which contains the cell which contains the custom MediaPlayerView, but I don't understand how to get a reference to this.

Answer 1

Try this:

class func topViewController(controller: UIViewController? = UIApplication.shared.keyWindow?.rootViewController) -> UIViewController? {
    if let navigationController = controller as? UINavigationController {
        return topViewController(controller: navigationController.visibleViewController)
    }
    if let tabController = controller as? UITabBarController {
        if let selected = tabController.selectedViewController {
            return topViewController(controller: selected)
        }
    }
    if let presented = controller?.presentedViewController {
        return topViewController(controller: presented)
    }
    return controller
}

Write your method as:

@objc func tapDetected() {
    print("tap!")

    let player = AVPlayer(url: self.mediaURL!)
    let controller = AVPlayerViewController()
    controller.player = player
    topViewController().present(controller, animated: true) {
        player.play()
    }
}

This will return you top vc in hierarchy. Hope it helps!

Answer 2

I would be interested in some feedback on this answer as I think its an example of me thinking about the iOS system the wrong way. What I eventually realized was that I was trying to put view controller code inside of a custom view. View controller code being the code to launch the AVPlayerViewController. Rather I should put this logic in my view controller.

What I did which works is use the collectionView delegate method didSelectItemAt indexPath: IndexPath inside of the view controller where the view controller logic for the collection view is held like so:

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    if collectionView == self.collectionView {
        let post = posts[indexPath.row]
        if post.isVideo == true {
            self.performSegue(withIdentifier: "playVideo", sender: nil)
        } else {
            print("is image. might go full screen one day here")
        }
}

This works and I believe it is better than writing a custom aspect of the view to launch the AVPlayerViewController. But it also could be that both approaches work - I really don't know enough about iOS development to make that call. Any comments are welcome.