如何在 Swift 中使用 AVPlayerViewController 检测全屏模式？

Question

我试图检测何时处于AVPlayerViewController全屏模式，但我很难做到这一点。我想知道用户何时选择展开按钮进入全屏，如下所示：

我已经根据这些建议添加了适当的观察者：

1. 检测纵向或横向全屏播放的视频
2. 如何检测 AVPlayerViewController 的全屏模式

相应的代码：

var avWidth:CGFloat = 375
var avHeight:CGFloat = 300

override func viewDidLoad()
{
    super.viewDidLoad()

    let path = NSBundle.mainBundle().pathForResource("cable pressback", ofType: "mp4")
    let url = NSURL.fileURLWithPath(path!)
    let player = AVPlayer(URL: url)

    playerViewController.player = player

    playerViewController.view.frame = CGRectMake(0, 100, self.view.frame.size.width, 300)

    playerViewController.view.translatesAutoresizingMaskIntoConstraints = true

    view.addSubview(playerViewController.view)

    self.addChildViewController(playerViewController)

    [playerViewController .addObserver(self, forKeyPath:"videoBounds" , options: NSKeyValueObservingOptions.New, context: nil)]

}

override func observeValueForKeyPath(keyPath: String?, ofObject object: AnyObject?, change: [String : AnyObject]?, context: UnsafeMutablePointer<Void>)
{
    print("playerViewController.view.frame = \(playerViewController.view.frame)")

    if keyPath == "videoBounds"
    {
        let rect = change!["new"]! as! NSValue

        if let newrect = rect.CGRectValue() as CGRect?
        {
            if newrect.width > 0 || newrect.height > 0
            {
                if avWidth > 0 || avHeight > 0
                {
                    if newrect.width > avWidth || newrect.height > avHeight
                    {
                        print("Full Screen")
                    }
                    else if newrect.width < avWidth || newrect.height < avHeight
                    {
                        print("Normal screen")
                    }
                }
                avWidth = newrect.width
                avHeight = newrect.height
            }
        }
    }
}

但是，它似乎永远不会到达代码print("Full Screen")。print("Normal Screen")无论播放器处于正常模式还是全屏模式，它都会被击中。

谢谢！

Answer 1

从 iOS 12 开始，我们可以使用这些AVPlayerViewControllerDelegate委托方法：

func playerViewController(AVPlayerViewController, willBeginFullScreenPresentationWithAnimationCoordinator: UIViewControllerTransitionCoordinator)
func playerViewController(AVPlayerViewController, willEndFullScreenPresentationWithAnimationCoordinator: UIViewControllerTransitionCoordinator)

Answer 2

更新为 Swift 3：

添加对象的观察者playerViewController：

playerViewController(self, forKeyPath: "videoBounds", options: NSKeyValueObservingOptions.new, context: nil)

override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?)
{
    if keyPath == "videoBounds"
    {
        if let rect = change?[.newKey] as? NSValue
        {
            if let newrect = rect.cgRectValue as CGRect?
            {
                // 200 is height of playerViewController in normal screen mode
                if newrect.size.height <= 200
                {
                    print("normal screen")
                }
                else
                {
                    print("full screen")
                }
            }
        }
    }
}