I can't play music with Spotify iOS SDK with Swift 4.0 - ios

Question

I have a struggle with Spotify SDK, I followed every step correctly, but I can't play music with my premium account on my project. There is no error or crash, my app directs me to the Spotify login page and after facebook login, It brings me back to my app again. Yesterday I'd get "logged in" print but today I can't. I'm trying to play a song after login and also manually as you see below. I'm wondering, am I lucky to find an answer?
override func viewDidLoad() {
super.viewDidLoad()
self.spotify()
NotificationCenter.default.addObserver(self, selector: #selector(GeneralNewsViewController.updateAfterFirstLogin), name: NSNotification.Name(rawValue: "SpotifySession"), object: nil)
}
func spotify() {
// insert redirect your url and client ID below
auth.redirectURL = URL(string: "correctCallbackURl")
auth.clientID = "correctClientID"
auth.requestedScopes = [SPTAuthStreamingScope, SPTAuthPlaylistReadPrivateScope, SPTAuthPlaylistModifyPublicScope, SPTAuthPlaylistModifyPrivateScope]
loginUrl = auth.spotifyWebAuthenticationURL()
}
func initializaPlayer(authSession:SPTSession){
if self.player == nil {
self.player = SPTAudioStreamingController.sharedInstance()
self.player!.playbackDelegate = self
self.player!.delegate = self
try! player?.start(withClientId: auth.clientID)
self.player!.login(withAccessToken: authSession.accessToken)
}
}
#objc func updateAfterFirstLogin () {
loginButton.isHidden = true
let userDefaults = UserDefaults.standard
if let sessionObj:AnyObject = userDefaults.object(forKey: "SpotifySession") as AnyObject? {
let sessionDataObj = sessionObj as! Data
let firstTimeSession = NSKeyedUnarchiver.unarchiveObject(with: sessionDataObj) as! SPTSession
self.session = firstTimeSession
initializaPlayer(authSession: session)
self.loginButton.isHidden = true
// self.loadingLabel.isHidden = false
}
}
func audioStreamingDidLogin(_ audioStreaming: SPTAudioStreamingController!) {
// after a user authenticates a session, the SPTAudioStreamingController is then initialized and this method called
print("logged in")
self.player?.playSpotifyURI("spotify:track:4aDLPXlzHZm26GppvRwms8", startingWith: 0, startingWithPosition: 0, callback: { (error) in
if (error != nil) {
print("playing!")
} else {
print(error?.localizedDescription)
}
})
}
#objc func play() {
player?.playSpotifyURI("spotify:track:4aDLPXlzHZm26GppvRwms8", startingWith: 0, startingWithPosition: 0, callback: { (err) in
if err != nil {
print(err?.localizedDescription)
} else {
}
})
}
class AppDelegate: UIResponder, UIApplicationDelegate ,UNUserNotificationCenterDelegate{
auth.redirectURL = URL(string: "correctCallbackURl")
auth.sessionUserDefaultsKey = "current session"}
func application(_ application: UIApplication, open url: URL, sourceApplication: String?, annotation: Any) -> Bool {
// 2- check if app can handle redirect URL
if auth.canHandle(auth.redirectURL) {
// 3 - handle callback in closure
auth.handleAuthCallback(withTriggeredAuthURL: url, callback: { (error, session) in
// 4- handle error
if error != nil {
print("error!")
}
// 5- Add session to User Defaults
let userDefaults = UserDefaults.standard
let sessionData = NSKeyedArchiver.archivedData(withRootObject: session!)
userDefaults.set(sessionData, forKey: "SpotifySession")
userDefaults.synchronize()
// 6 - Tell notification center login is successful
NotificationCenter.default.post(name: Notification.Name(rawValue: "loginSuccessfull"), object: nil)
})
return true
}
return false
}}

Answer 1

It looks like you're subscribed to the wrong notification, you're subscribing to "SpotifySession" but posting "loginSuccessfull"
this answer will help you making this kind of mistake in the future by having enums for events in a simple way.
good debugging is also key, you could've probably solved this problem with some breakpoints to see where you went wrong.
cheers