title: Why wont UIView display a second time?
body: <p>I'm trying to figure out why my newDogView will only present once. This app takes a dog photo, stores it in a struct with some other info, and plots that dog on a map view as an annotation. When you press the newDogButton, a UIImagePickerController is presented. Once it's dismissed, a preview shows up with some options to add info. </p>
  
  <p>Once the user submits the dog photo, everything is saved to a struct. The problem is that when the user taps the newDogButton a second time, the newDogView is never made visible again. </p>
  
  <p>I think it might have something to do with the way I'm calling .removeFromSuperview().</p>
  
  <p>Please let me know if anything stands out. I'm new to this!</p>
  
  <pre><code>class ViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate, CLLocationManagerDelegate, UITextFieldDelegate {
  
  var image: UIImage?
  var location: CLLocation?
  var dogs: [Dog] = []
  @IBOutlet var newDogButton: UIButton!
  @IBOutlet var newDogScore: UILabel!
  @IBOutlet var newDogName: UITextField!
  @IBOutlet var newDogView: UIView!
  @IBOutlet var preview: UIImageView!
  @IBOutlet var map: MKMapView!
  let locman = CLLocationManager()
  
  override func viewDidLoad() {
      super.viewDidLoad()
  
      self.locman.delegate = self
      self.locman.requestWhenInUseAuthorization()
      self.locman.desiredAccuracy = kCLLocationAccuracyBest
      self.map.mapType = .standard
      self.map.showsUserLocation = true
      self.map.userTrackingMode = .follow
      self.newDogName.delegate = self
  
  }
  
  override func viewWillAppear(_ animated: Bool) {
      super.viewWillAppear(true)
      self.navigationController?.setNavigationBarHidden(true, animated: false)
  }
  
  @IBAction func newDogTapped(_ sender: Any) {
      presentCamera()
      self.locman.requestLocation()
  }
  
  func presentCamera() {
      let source = UIImagePickerControllerSourceType.camera
      guard UIImagePickerController.isSourceTypeAvailable(source)
          else {
              let alert = UIAlertController(title: "Camera Error", message: "Oops! Looks like Dog Spotter doesn't have access to your camera! Please open Settings to give Dog Spotter permission to use the camera.", preferredStyle: .alert)
              present(alert, animated: true)
              return
      }
      let camera = UIImagePickerController()
      camera.sourceType = source
      camera.delegate = self
      camera.allowsEditing = true
  
      self.present(camera, animated: true)
  }
  
  func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
      image = info[UIImagePickerControllerOriginalImage] as? UIImage
      if let editedImage = info[UIImagePickerControllerEditedImage] as? UIImage {
          image = editedImage
      }
  
      self.dismiss(animated: true, completion: {
          self.setupNewDogView()
      })
  }
  
  func setupNewDogView() {
      newDogView.isHidden = true
      map.isUserInteractionEnabled = false
      view.addSubview(newDogView)
      newDogView.translatesAutoresizingMaskIntoConstraints = false
      newDogView.widthAnchor.constraint(equalTo: view.widthAnchor, multiplier: 1, constant: -50).isActive = true
      newDogView.heightAnchor.constraint(equalTo: view.heightAnchor, multiplier: 1, constant: -200).isActive = true
      newDogView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
      newDogView.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true
      preview.image = self.image
      newDogView.layer.cornerRadius = 25
      newDogButton.layer.cornerRadius = 25
      newDogView.isHidden = false
  }
  
  func locationManager(_ manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
      let loc = locations.last!
      let coord = loc.coordinate
      location = loc
      print("You are at \(coord.latitude) \(coord.longitude)")
  }
  
  @IBAction func submitDog(_ sender: Any) {
      let newDog = Dog(name: newDogName.text!, score: Int(newDogScore.text!)!, picture: image!, location: location!)
      dogs.append(newDog)
      print(dogs.last!)
      UIView.animate(withDuration: 0.5, animations: {
          self.newDogView.alpha = 0
      }) { _ in
          self.newDogView.removeFromSuperview()
          self.map.isUserInteractionEnabled = true
      }
  }
  
  func locationManager(_ manager: CLLocationManager, didFailWithError error: Error) {
      return
  }
  
  func textFieldShouldReturn(_ textField: UITextField) -&gt; Bool {
      textField.resignFirstResponder()
      return true
  }
  
  override func touchesBegan(_ touches: Set&lt;UITouch&gt;, with event: UIEvent?) {
      self.view.endEditing(true)
  }
  </code></pre>
  
  <p>}</p>
  
  <p><a href="https://i.stack.imgur.com/mBcC3.png" rel="nofollow noreferrer">Here's an image of my storyboard, if that's helpful!</a></p>
  
  <p>Here's the console output when trying to display the view twice.</p>
  
  <blockquote>
    <p>2017-08-10 16:27:59.263965-0700 DogSpotter[960:682273]  - changing property contentsGravity in transform-only layer, will have no effect
    2017-08-10 16:27:59.264702-0700 DogSpotter[960:682273]  - changing property contentsGravity in transform-only layer, will have no effect
    2017-08-10 16:27:59.374063-0700 DogSpotter[960:682273] libMobileGestalt MobileGestaltSupport.m:153: pid 960 (DogSpotter) does not have sandbox access for frZQaeyWLUvLjeuEK43hmg and IS NOT appropriately entitled
    2017-08-10 16:27:59.374151-0700 DogSpotter[960:682273] libMobileGestalt MobileGestalt.c:550: no access to InverseDeviceID (see )
    2017-08-10 16:28:03.321761-0700 DogSpotter[960:682273] [MC] System group container for systemgroup.com.apple.configurationprofiles path is /private/var/containers/Shared/SystemGroup/systemgroup.com.apple.configurationprofiles
    2017-08-10 16:28:03.322541-0700 DogSpotter[960:682273] [MC] Reading from public effective user settings.
    >
    You are at 45.4874888481593 -122.734139806728
    Dog(name: "Rex", score: 11, picture:  size {750, 750} orientation 0 scale 1.000000, location: &lt;+45.48748885,-122.73413981> +/- 65.00m (speed -1.00 mps / course -1.00) @ 8/10/17, 4:28:07 PM Pacific Daylight Time)
    >
    2017-08-10 16:28:44.979563-0700 DogSpotter[960:682273] [App] if we're in the real pre-commit handler we can't actually add any new fences due to CA restriction
    2017-08-10 16:28:44.981668-0700 DogSpotter[960:682273] [App] if we're in the real pre-commit handler we can't actually add any new fences due to CA restriction
    You are at 45.4874600607505 -122.734123729821</p>
  </blockquote>