LoginViewController whose view is not in the window hierarchy! in Appldelegate

Question

My goal is to check if there is a token in the keychain, if there isn't then simply show a login view controller screen. The problem right now, is that I get this error. I wrote this code in AppDelegate.swift

.LoginViewController: 0x7ff59b619820> on whose view is not in the window hierarchy!

Here's the code

   func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {

     let keychain = Keychain(server: "https://app.herokuapp.com", protocolType: .HTTPS)

     if ((try? keychain.contains("token")) != nil) {
        showLoginScreen()
     } else {

     }
      return true
     }

    func showLoginScreen() -> Void {
        let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
        let setViewController = mainStoryboard.instantiateViewControllerWithIdentifier("loginView") as! LoginViewController
        let rootViewController = self.window!.rootViewController
        rootViewController?.presentViewController(setViewController, animated: false, completion: nil)
    }

score 1 · Answer 1 · edited May 23 '17 at 12:31

try this

add self.window.makeKeyAndVisible() before present

self.window.makeKeyAndVisible()

Update

   let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
    let setViewController = mainStoryboard.instantiateViewControllerWithIdentifier("loginView") as! LoginViewController
      self.window.makeKeyAndVisible()
    self.window!.rootViewController.presentViewController(setViewController, animated: false, completion: nil)

for additional information see this

score 1 · Answer 2 · answered May 19 '16 at 08:50

By setting your view controller as UINavigationControllers rootviewcontroller and then adding navigationcontroller as Windows rootviewcontrollers will work check out the modified code below:

func showLoginScreen() -> Void {
    self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
    let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
    let vc = mainStoryboard.instantiateViewControllerWithIdentifier("loginView") as UIViewController
    let navigationController = UINavigationController(rootViewController: vc)
    self.window!.rootViewController = navigationController
    self.window!.makeKeyAndVisible()
}

If you like to switch between two viewcontrollers depending on the LoginStatus i suggest you to follow the below method:

self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
if LofinStatus == true{
        let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
        let vc = mainStoryboard.instantiateViewControllerWithIdentifier("My_Offer") as UIViewController
        let navigationController = UINavigationController(rootViewController: vc)
        self.window!.rootViewController = navigationController
    }else{
        let mainStoryboard: UIStoryboard = UIStoryboard(name: "Login", bundle: nil)
        let vc = mainStoryboard.instantiateViewControllerWithIdentifier("loginView") as UIViewController
        let navigationController = UINavigationController(rootViewController: vc)
        self.window!.rootViewController = navigationController
    }
self.window!.makeKeyAndVisible()

NOTE: In the above code i had used two storyboards Main and Login It worked for me perfectly,give it a try and let me know the result.Thank You

LoginViewController whose view is not in the window hierarchy! in Appldelegate

2 Answers2