Spotify Authentication with iOS SDK in Swift

SpotifyAuth.swift

//
//  ViewController.swift
//  iOSSDKSwift
//
//  Created by Arielle Vaniderstine on 2017-04-06.
//  Copyright © 2017 Arielle Vaniderstine. All rights reserved.
//

import UIKit

class ViewController: UIViewController, SPTAudioStreamingPlaybackDelegate, SPTAudioStreamingDelegate {
    
    var auth = SPTAuth.defaultInstance()!
    var session:SPTSession!
    var player: SPTAudioStreamingController?
    var loginUrl: URL?
    
    @IBOutlet weak var loginButton: UIButton!
    
    @IBAction func loginPressed(_ sender: Any) {
        UIApplication.shared.open(loginUrl!, options: [:], completionHandler: nil)
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        setup()
        NotificationCenter.default.addObserver(self, selector: #selector(ViewController.updateAfterFirstLogin), name: NSNotification.Name(rawValue: "loginSuccessful"), object: nil)
    }
    
    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
            initializePlayer(authSession: session)
        }
    }
    
    func initializePlayer(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)
            print("Player has been initialized")
        }
    }
    
    func audioStreamingDidLogin(_ audioStreaming: SPTAudioStreamingController!) {
        // after a user authenticates a session, the SPTAudioStreamingController is then initialized and this method called
        print("logged in")
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }
    
    func setup () {
        // insert redirect your url and client ID below
        let redirectURL = "your-bundle-id://your-scheme" // put your redirect URL here
        let clientID = "" // put your client ID here
        auth.redirectURL     = URL(string: redirectURL)
        auth.clientID        = clientID
        // put your scopes here
        auth.requestedScopes = [SPTAuthStreamingScope, SPTAuthPlaylistReadPrivateScope, SPTAuthPlaylistModifyPublicScope, SPTAuthPlaylistModifyPrivateScope, SPTAuthUserLibraryReadScope]
        loginUrl = auth.spotifyWebAuthenticationURL()
    }


}