Resuming AVPlayer after being interrupted with SwiftUI

Question

I'm building a radio streaming app using AVPlayer and AVPlayerItem. I've built my app to keep playing the radio in the background like this:

do {
    try AVAudioSession.sharedInstance().setCategory(.playback)
    try AVAudioSession.sharedInstance().setActive(true)
} catch {
   print(error)
}

After the AVPlayer is interrupted (for example, when the user receives a call) the AVPlayer isn't resuming playing. I need to actively play it again in order to listen to the streaming.

How can I make the AVPlayer to automatically resume after being interrupted using SwiftUI? (I've found some solutions but non of them is suitable for working with SwiftUI.

Thank you!

Answer 1

There's nothing related to SwiftUI, or UI in general, to restart playback after an interruption.

As said in apple documentation:

First register to the notification of the interruption:

func registerForNotifications() {
    NotificationCenter.default.addObserver(self,
                                           selector: #selector(handleInterruption),
                                           name: .AVAudioSessionInterruption,
                                           object: AVAudioSession.sharedInstance())
}

Then handle the notification like this:

func handleInterruption(_ notification: Notification) {
    guard let info = notification.userInfo,
        let typeValue = info[AVAudioSessionInterruptionTypeKey] as? UInt,
        let type = AVAudioSessionInterruptionType(rawValue: typeValue) else {
            return
    }
    if type == .began {
        // Interruption began, take appropriate actions (save state, update user interface)
    }
    else if type == .ended {
        guard let optionsValue =
            userInfo[AVAudioSessionInterruptionOptionKey] as? UInt else {
                return
        }
        let options = AVAudioSessionInterruptionOptions(rawValue: optionsValue)
        if options.contains(.shouldResume) {
            // Interruption Ended - playback should resume
        }
    }
}

If that doesn't help, you could explain better the issue you are having with other solutions that don't work in your case.

Answer 2

SwiftUI

Call the .onReceive function on your play button like this:

.onReceive(NotificationCenter.default.publisher(for: AVAudioSession.interruptionNotification)) { event in
    guard let info = event.userInfo,
        let typeValue = info[AVAudioSessionInterruptionTypeKey] as? UInt,
        let type = AVAudioSession.InterruptionType(rawValue: typeValue) else {
            return
    }
    if type == .began {
        // Interruption began, take appropriate actions (save state, update user interface)
    }
    else if type == .ended {
        guard let optionsValue =
            info[AVAudioSessionInterruptionOptionKey] as? UInt else {
                return
        }
        let options = AVAudioSession.InterruptionOptions(rawValue: optionsValue)
        if options.contains(.shouldResume) {
            // Interruption Ended - playback should resume
            player.play()
        }
    }
}