How to resume background audio in Swift 2 / AVPlayer?

I am learning Swift as my first programming language.

I've struggled for many hours to resume background audio playback after interruption (eg call)

What should happen:

  • Audio keeps playing when app goes to background (works)
  • When interrupted by a call, get the notification for interruption began (works)
  • When call ends, get the notification for interruption ends (works)
  • Resume playing the audio ( does NOT work - hear nothing )
  • Really appreciate any help! Thanks

    Notes:

  • The app is registered for background audio and plays fine before interruption
  • I have tried with and without the time delay to resume playing - neither work
  • Code:

    import UIKit
    import AVFoundation
    
    var player: AVQueuePlayer!
    
    class ViewController: UIViewController {
    
        override func viewDidLoad() {
            super.viewDidLoad()
            do {
                try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback)
                try AVAudioSession.sharedInstance().setActive(true, withOptions: .NotifyOthersOnDeactivation)
            } catch { }
            let songNames = ["music"]
            let songs = songNames.map { AVPlayerItem(URL:
                NSBundle.mainBundle().URLForResource($0, withExtension: "mp3")!) }
            player = AVQueuePlayer(items: songs)
    
            let theSession = AVAudioSession.sharedInstance()
            NSNotificationCenter.defaultCenter().addObserver(self,
                selector:"playInterrupt:",
                name:AVAudioSessionInterruptionNotification,
                object: theSession)
    
            player.play()
        }
    
        func playInterrupt(notification: NSNotification) {
    
            if notification.name == AVAudioSessionInterruptionNotification
                && notification.userInfo != nil {
    
                var info = notification.userInfo!
                var intValue: UInt = 0
                (info[AVAudioSessionInterruptionTypeKey] as! NSValue).getValue(&intValue)
                if let type = AVAudioSessionInterruptionType(rawValue: intValue) {
                    switch type {
                    case .Began:
                        print("aaaaarrrrgggg you stole me")
                        player.pause()
    
                    case .Ended:
                        let timer = NSTimer.scheduledTimerWithTimeInterval(3, target: self, selector: "resumeNow:", userInfo: nil, repeats: false)
                    }
                }
            }
        }
        func resumeNow(timer : NSTimer) {
            player.play()
            print("attempted restart")
        }
    }
    

    Finally got it!

    Solution: added the mixable option by changing the setCategory line to be:

    AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback, withOptions: AVAudioSessionCategoryOptions.MixWithOthers )


    I wrote a code like this and successfully resumed the audio from the phone call ended. I was build on Xcode 6.4 and ran the app on my iPhone 4S.

    var player: AVQueuePlayer! = nil
    
    override func viewDidLoad()
    {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
    }
    
    override func viewDidAppear(animated: Bool)
    {
        super.viewDidAppear(true)
    
        var song = AVPlayerItem(URL: NSBundle.mainBundle().URLForResource("AlmostAYearAgo", withExtension: "mp3")!)
        player = AVQueuePlayer(items: [song])
    
        let theSession = AVAudioSession.sharedInstance()
    
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "playInterrupt:", name: AVAudioSessionInterruptionNotification, object: theSession)
    
        player.play()
    }
    
    override func didReceiveMemoryWarning()
    {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
    func playInterrupt(notification: NSNotification)
    {
        if notification.name == AVAudioSessionInterruptionNotification && notification.userInfo != nil
        {
            var info = notification.userInfo!
            var intValue: UInt = 0
    
            (info[AVAudioSessionInterruptionTypeKey] as! NSValue).getValue(&intValue)
    
            if let type = AVAudioSessionInterruptionType(rawValue: intValue)
            {
                switch type
                {
                case .Began:
                    print("aaaaarrrrgggg you stole me")
                    player.pause()
                case .Ended:
                    let timer = NSTimer.scheduledTimerWithTimeInterval(3, target: self, selector: "resumeNow:", userInfo: nil, repeats: false)
                }
            }
        }
    }
    
    func resumeNow(timer : NSTimer)
    {
        player.play()
        print("attempted restart")
    }
    

    对于我结束中断后重新加载播放器解决问题:

        func interruptionNotification(_ notification: Notification) {
        guard let type = notification.userInfo?[AVAudioSessionInterruptionTypeKey] as? UInt,
          let interruption = AVAudioSessionInterruptionType(rawValue: type) else {
            return
        }
        if interruption == .ended && playerWasPlayingBeforeInterruption {
          player.replaceCurrentItem(with: AVPlayerItem(url: radioStation.url))
          play()
        }
      }
    
    链接地址: http://www.djcxy.com/p/87862.html

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