Swift 4 start with custom ViewController - ios

Question

I have chatting app. I decide to create SlideShow tutorial for it. Now I have problem. How can I run TutorialVC just once when user install the app?
Usually app starts with AuthVC. Now I want to run tutorialVC just once, and then when user close app and run it again, from auth like usually.
My tutorial VC:
class TutorialViewController: UIViewController, UIScrollViewDelegate {
#IBAction func understandButtonAction(_ sender: Any) {
}
#IBOutlet weak var understandButton: UIButton!
#IBOutlet weak var tutorialPageControl: UIPageControl!
#IBOutlet weak var tutorialScrollView: UIScrollView!
var images: [String] = ["1","2","3","4"]
var frame = CGRect(x: 0, y: 0, width: 0, height: 0)
override func viewDidLoad() {
super.viewDidLoad()
setup()
addSlider()
setupButton()
}
//===============================
//EVTAuthorizationViewController
//===============================
override func viewWillAppear(_ animated: Bool) {
UIApplication.shared.keyWindow?.windowLevel = UIWindowLevelStatusBar
}
override func viewWillDisappear(_ animated: Bool) {
UIApplication.shared.keyWindow?.windowLevel = UIWindowLevelNormal
}
//AddButton
func setupButton(){
understandButton.layer.cornerRadius = 20
}
#IBAction func buttonAction(_ sender: Any?) {
print("Successful")
}
//ScrollBars
func setup(){
self.understandButton.isHidden = true
tutorialScrollView.showsHorizontalScrollIndicator = false
tutorialScrollView.showsVerticalScrollIndicator = false
}
//ScrollView method
//=============================
func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
var pageNumber = scrollView.contentOffset.x / scrollView.frame.size.width
tutorialPageControl.currentPage = Int(pageNumber)
if tutorialPageControl.currentPage == 3{
self.understandButton.isHidden = false
}else{
self.understandButton.isHidden = true
}
}
//Addslider with photo
func addSlider(){
tutorialPageControl.numberOfPages = images.count
for index in 0..<images.count{
let xPos = self.view.frame.size.width * CGFloat(index)
frame.origin.x = tutorialScrollView.frame.size.width * CGFloat(index)
//frame.size = view.frame.size
let imageView = UIImageView(frame: CGRect(x: xPos, y: 0, width: self.view.frame.width, height: self.view.frame.size.height))
imageView.image = UIImage(named: images[index])
imageView.contentMode = .scaleAspectFill
self.tutorialScrollView.addSubview(imageView)
}
tutorialScrollView.contentSize = CGSize(width: (view.frame.size.width * CGFloat(images.count)), height: view.frame.size.height)
tutorialScrollView.delegate = self
}
}

Answer 1

Use userDefaults. I suppose the understandButton is the button the user hits to skip the tutorial, so when when it's tapped set a true bool value for a key that you are going to use, here I've chosen "tutorial presented":
#IBAction func understandButtonAction(_ sender: Any) {
UserDefaults.standard.set(true, forKey: "tutorial presented")
}
and when the app launches, in the AppDelegate
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey : Any]? = nil) -> Bool {
let window = (UIApplication.shared.delegate as! AppDelegate).window
let storyboard = UIStoryboard(name: "MyStoryboardName", bundle: nil)
if UserDefaults.standard.bool(forKey: "tutorial presented") == true {
let controller = storyboard.instantiateViewController(withIdentifier: "Your Navigation controller name")
window?.rootViewController = tutorialViewController()
} else {
let tutorial = storyboard.instantiateViewController(withIdentifier: "Your tutorial controller name")
window?.rootViewController = tutorial
}
window?.makeKeyAndVisible()
return true
}

Answer 2

You can use a flag and store it via NSUserDefaults.
extension UserDefaults {
private static let didLaunchAppOnceKey = "didLaunchAppOnce"
var didLaunchAppOnce: Bool {
get { return bool(forKey: UserDefaults.didLaunchAppOnceKey) }
set { set(newValue, forKey: UserDefaults.didLaunchAppOnceKey) }
}
}
Then before presenting your view controller, check if the flag is set:
if !UserDefaults.standard.didLaunchAppOnce {
// Set the flag to true, so on next launch, we won't enter in the if again
UserDefaults.standard.didLaunchAppOnce = true
// Present your VC
…
}