Zystkmt

Everytime I leave this ViewController and then come back the quiz starts back to question 1. I want it to resume from where I left off.

I believe why it keeps resetting to zero is because my initial "questionNumber" is set to 0 but I'm not sure how to set its value to the value in Firebase correctly. I get error after error. I've tried so many different ways but none of them seem to work and resume from where I left off.
Thanks for your help! PLEASE help me!

class CryptoViewController: UIViewController {



    var questionList = CryptoBank()

    var score = 0

    var pickedQuestion = 0

    var uid = FIRAuth.auth()?.currentUser?.uid

    var questionNumber = 0



    @IBOutlet weak var questionViewer: UILabel!

    @IBOutlet weak var choiceOne: UIButton!

    @IBOutlet weak var choiceTwo: UIButton!

    @IBOutlet weak var choiceThree: UIButton!

    @IBOutlet weak var scoreLabel: UILabel!

    @IBOutlet weak var questionNumberView: UILabel!

    @IBOutlet weak var progressBarView: UIView!



    override func viewDidLoad() {

        super.viewDidLoad()



        choiceOne.titleLabel?.textAlignment = NSTextAlignment.center

        choiceTwo.titleLabel?.textAlignment = NSTextAlignment.center

        choiceThree.titleLabel?.textAlignment = NSTextAlignment.center

        self.navigationController?.navigationBar.setBackgroundImage(UIImage(), for: .default)

        self.navigationController?.navigationBar.shadowImage = UIImage()

        self.navigationController?.navigationBar.isTranslucent = true

        self.navigationController?.view.backgroundColor = .clear

       update()

    }





    @IBAction func buttonPressed(_ sender: AnyObject) {

        if sender.tag == 1 {

            pickedQuestion = 1}

        else if sender.tag == 2 {

            pickedQuestion = 2}

        else if sender.tag == 3 {

            pickedQuestion = 3}

        checkAnswer()

        questionNumber += 1

        nextQuestion()

    }



    func checkAnswer(){

        let correctAnswer = questionList.cryptoBank[questionNumber].answer

        if pickedQuestion == correctAnswer {

            score += 1

        }else{

            print("Wrong Answer")

        }

    }



    func updateFirebase(){

        let ref = FIRDatabase.database().reference()

        guard let uid = FIRAuth.auth()?.currentUser!.uid else{

            return}

        ref.child("Users").child(uid).child("Cryptoquiz").child("Question Number").setValue(questionNumber)

        ref.child("Users").child(uid).child("Cryptoquiz").child("Score").setValue(score)

    }



    func nextQuestion(){

        if questionNumber <= 9 {

            update()

        } else{



            scoreLabel.text = "Score: (score)"

            let alert = UIAlertController(title: "Done!", message: "Would you like to restart?", preferredStyle: .alert)

            let restartAction = UIAlertAction(title: "Restart", style: .default, handler: { (UIAlertAction) in

                self.startAgain()

            })

            alert.addAction(restartAction)

            present(alert, animated: true, completion: nil)

        }}



    func update(){

        let nextQuest = questionList.cryptoBank[questionNumber]

        questionViewer.text = nextQuest.question

        choiceOne.setTitle(nextQuest.choice1, for: .normal)

        choiceTwo.setTitle(nextQuest.choice2, for: .normal)

        choiceThree.setTitle(nextQuest.choice3, for: .normal)

        scoreLabel.text = "Score: (score)"

        questionNumberView.text = "Question: (questionNumber + 1)"

        progressBarView.frame.size.width = (view.frame.size.width/9)  * CGFloat(questionNumber + 1)

        updateFirebase()



    }





    }

You can save your progress in UserDefaults in viewDidDisappear() like this:

UserDefaults.standard.set(questionNumber, forKey: "questionNumber")

And then every time you open your view, in viewDidLoad() or in viewDidAppear() you update your questionNumber like this:

let questionNumberSaved = UserDefaults.standard.integer(forKey: “questionNumber”) ?? 0

questionNumber = questionNumberSaved

Then after doing this you call your updateFirebase() method