Open the last opened view controller when closing and opening the app - ios

Question

I want to be able to close and reopen the same view controller on my app. The reason I want to do this is because I have a "tutorial" scene that I only want to be brought up the first time you open the app. Every other time I want the app to instantly open up the second view controller. Here is my code:
for GameViewController:
UserDefaults.standard.set(0, forKey: "View")
for GameViewController2:
UserDefaults.standard.set(1, forKey: "View")
for AppDelegate:
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions:
[UIApplicationLaunchOptionsKey: Any]?) -> Bool {
let viewCount = UserDefaults.standard.integer(forKey: "View")
var VC = UIViewController()
let storyboard : UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
print(viewCount)
if viewCount == 0 {
//FirstView should initiate
VC = storyboard.instantiateViewController(withIdentifier: "First") as! GameViewController
} else {
//SecondView should inititate
VC = storyboard.instantiateViewController(withIdentifier: "Second") as! GameViewController2
}
self.window?.makeKeyAndVisible()
self.window?.rootViewController = VC
return true
}
The problem is that every single time I open the app, it always starts on my first view controller instead of my second view controller. Any help would be appreciated.

Answer 1

Based on the code above, you are not calling UserDefaults.synchronize
var userDefaults = UserDefaults.standard
userDefaults.set(1, forKey:"View")
userDefaults.synchronize()
In both cases it must be synchronised as this saves changes to disk
Update: As noted by #cs4alhaider synchronize() is not needed in Swift 4, so this problem would not occur anymore.