How can I get my app to wait for a permission request to complete?-CodePudding

Am working on a recording app from scratch and it just has the basics. Within my info.plist I do set Privacy - Microphone Usage Description

Still, I always want to check the "privacy permission" on the microphone because I know people can hit "No" by accident.

However, whatever I try, the app keeps running without waiting for the iOs permission alert to pop up and complete.

    let mediaType = AVMediaType.audio

    let mediaAuthorizationStatus = AVCaptureDevice.authorizationStatus(for: mediaType)
    switch mediaAuthorizationStatus {
        case .denied:
            print (".denied")
        case .authorized:
            print ("authorized")
        case .restricted:
            print ("restricted")

        case .notDetermined:
            print("huh?")

        let myQue = DispatchQueue(label: "get perm")
        myQue.sync 
        {
                AVCaptureDevice.requestAccess(for: .audio, completionHandler: { (granted: Bool) in
                    if granted {
                    } else {
                    }
            })
        }
    default:
        print ("not a clue")
    }

CodePudding user response：

I think you are already on the main thread and trying to DispatchQueue.main.sync from the Main thread. Check it like this.

if Thread.isMainThread {
  // you are already on the main thread
} else {
  DispatchQueue.main.sync {
    // do stuff
  }
}

CodePudding user response：

without waiting for the iOs permission alert to pop up and complete

Great line, partially describing possible solution (imho).

AFAIK all UIAlertController-related routines are richly flavoured with completions. I'd try to put recording logic trigger inside the completion handler of method that presents the alert itself.

CodePudding user response：

Misusing DispatchQueue to force an asynchronous task to become synchronous is a very bad practice.

Either use a completion handler

func avAuthorization(completion : @escaping (Bool) -> Void)
{
    let mediaType = AVMediaType.audio
    let mediaAuthorizationStatus = AVCaptureDevice.authorizationStatus(for: mediaType)
    switch mediaAuthorizationStatus {
        case .denied, .restricted: completion(false)
        case .authorized: completion(true)
        case .notDetermined:
            AVCaptureDevice.requestAccess(for: .audio) { granted in
                completion(granted)
            }
    }
}

Or in Swift 5.5 an async function

func avAuthorization() async -> Bool
{
    let mediaType = AVMediaType.audio
    let mediaAuthorizationStatus = AVCaptureDevice.authorizationStatus(for: mediaType)
    switch mediaAuthorizationStatus {
        case .denied, .restricted: return false
        case .authorized: return true
        case .notDetermined: return await AVCaptureDevice.requestAccess(for: .audio)
    }
}