title: removeFromSuperview() not working
body: <p>I wanted to blur the background when the touch id is asked and once the authorization is successfull, the viewcontroller needs to be visible.But this is not happening.The viewcontroller is still blurred even if authorization is successfull.Can anyone help me on how to solve this?</p>
  
  <pre><code>import UIKit
  import LocalAuthentication
  class TabBarViewController: UITabBarController {
  
  @IBOutlet weak var noteTabBar: UITabBar!
  
  override func viewDidLoad() {
  super.viewDidLoad()
      self.authenticateUser()
      self.tabBar.hidden = false
      self.view.addGestureRecognizer(self.revealViewController().panGestureRecognizer())
  
      let userDefaults = NSUserDefaults.standardUserDefaults()
      userDefaults.setObject(false, forKey: "sendModeToggle")
      userDefaults.setObject("Avenir-Medium", forKey: "font")
       userDefaults.setObject(13, forKey:"fontSize")
              // Do any additional setup after loading the view.
  }
  override func didReceiveMemoryWarning() {
      super.didReceiveMemoryWarning()
      // Dispose of any resources that can be recreated.
  }
  
  
  /*
  // MARK: - Navigation
  
  // In a storyboard-based application, you will often want to do a little preparation before navigation
  override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
      // Get the new view controller using segue.destinationViewController.
      // Pass the selected object to the new view controller.
  }
  */
  
  // MARK: Touch ID Authentication
  
  func authenticateUser()
  {
      let context = LAContext()
      var error: NSError?
      let reasonString = "Authentication is needed to access your app! :)"
  
      let blurEffect = UIBlurEffect(style: .Light)
      let blurVisualEffectView = UIVisualEffectView(effect: blurEffect)
      blurVisualEffectView.frame = view.bounds
      self.view.addSubview(blurVisualEffectView)
  
      if context.canEvaluatePolicy(LAPolicy.DeviceOwnerAuthenticationWithBiometrics, error: &amp;error)
      {
  
          context.evaluatePolicy(LAPolicy.DeviceOwnerAuthenticationWithBiometrics, localizedReason: reasonString, reply: { (success, policyError) -&gt; Void in
  
              if success
              {
                  print("Authentication successful! :) ")
                  blurVisualEffectView.removeFromSuperview()
  
              }
              else
              {
                  switch policyError!.code
                  {
                  case LAError.SystemCancel.rawValue:
                      print("Authentication was cancelled by the system.")
                  /*case LAError.UserCancel.rawValue:
                      print("Authentication was cancelled by the user.")
                   */   
                  case LAError.UserFallback.rawValue:
                      print("User selected to enter password.")
                      NSOperationQueue.mainQueue().addOperationWithBlock({ () -&gt; Void in
                          self.showPasswordAlert()
                          blurVisualEffectView.removeFromSuperview()
  
                      })
                  default:
                      print("Authentication failed! :(")
                      NSOperationQueue.mainQueue().addOperationWithBlock({ () -&gt; Void in
                          self.showPasswordAlert()
                          blurVisualEffectView.removeFromSuperview()
  
                      })
                  }
              }
  
          })
  
      }
      else
      {
          print(error?.localizedDescription)
          NSOperationQueue.mainQueue().addOperationWithBlock({ () -&gt; Void in
              self.showPasswordAlert()
          })
      }
  
  
  }
  
  }
  </code></pre>