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iOS

Kevin Zoltany
Kevin Zoltany
16,282 Points
Posted by Kevin Zoltany
Kevin Zoltany
16,282 Points

Having issues with changing viewcontrollers after Touch ID Succeeds

I'm having an issue with changing view controllers in local authentication. When all the code executes in the success if statement the view controller does not change even though I'm telling it to. I've tried everything that I know but nothing works. Here is my local authentication code.

  let authentication = LAContext()
  var authenticationError: NSError?

  authentication.canEvaluatePolicy(LAPolicy.DeviceOwnerAuthenticationWithBiometrics, error: &authenticationError)

  if (authenticationError != nil) {
    // Authentication Not available for this version of iOS
    self.gotoMainViewController()
  } else {
    authentication.evaluatePolicy(LAPolicy.DeviceOwnerAuthenticationWithBiometrics, localizedReason: "Access Application using Touch ID") {
      (success, error) in
      if (error != nil) {
        // There was an error - user likley pressed cancel
        print(error?.localizedDescription)
      } else {
        if (success) {
          dispatch_async(dispatch_get_main_queue()) {
            self.gotoMainViewController()
          }
        } else {
          self.showFailedTouchIDError.showAlert()
        }
      }
    }
  }

Here is the gotoMainViewController() code.

  func gotoMainViewController() {
   let viewController = MainViewController()
   self.navigationController?.pushViewController(viewController, animated: true)
  }

1 Answer

Michael Reining
Michael Reining
10,101 Points
Michael Reining
Michael Reining
10,101 Points

Hi Kevin,

Have you tried to use a different method to instantiate your view controller?

What about this:

func gotoMainViewController() {

    if let mainVC = storyboard?.instantiateViewControllerWithIdentifier("mainVC") {

        dispatch_async(dispatch_get_main_queue()) { () -> Void in

            navigationController?.pushViewController(mainVC, animated: true)

        }

    }

}

Hope that helps,

Mike

PS: Thanks to the awesome resources on Team Treehouse, I just launched my first app. :-)

Code! Learn how to program with Swift

Kevin Zoltany
Kevin Zoltany
16,282 Points
Kevin Zoltany
Kevin Zoltany
16,282 Points

Sorry to say this, but i don't use interface builder, so the method that you suggested will unfortunately not work for me.