title: Value of type 'UIViewController' has no member 'mapView'
body: <p>this is my fuction in util file. it complains about "Value of type 'UIViewController' has no member 'mapView'"</p>
  
  <pre><code>func removeSpecificCustomAnnotation(annotationArray: [CustomPointAnnotation], annotationIdToRemove: String, viewController: UIViewController) {
      for annotation in annotationArray {
          if let ID = annotation.locationID, ID == annotationIdToRemove {
              viewController.mapView.removeAnnotation(annotation)
          }
      }
  }
  </code></pre>
  
  <p>i am not allowed to answer anymore. i post my working things here</p>
  
  <p>this is working function. I want to remove a annotation on the map</p>
  
  <ol>
  <li>in my viewController.swift</li>
  <li>declare var mapView = MKMapView()</li>
  <li>function to display all annotations -> i dont put here</li>
  <li>now, i want to remove one of annotation that displayed above</li>
  <li>i have the ID of annotation (you need to use a custom annotation to do this)</li>
  <li>the ID of annotation is generated by a function based on the latitude and longitude</li>
  <li>now, i need to find the annotation that has that ID and remove it</li>
  <li><p>i get all annotations on the map</p>
  
  <p>let annotations = mapView.annotations.filter {
              $0 !== self.mapView.userLocation
          }</p></li>
  <li><p>loop the annotation arrays and then remove that one i need </p>
  
  <pre><code>for annotation in annotations {
  
      let getLat: CLLocationDegrees = annotation.coordinate.latitude
      let getLon: CLLocationDegrees = annotation.coordinate.longitude
  
      let cllocation: CLLocation =  CLLocation(latitude: getLat, longitude: getLon)
  
      let locationID = Utils.generateLocationID(newcllocation: cllocation, existingCllocationToEdit: nil)
  
      if locationID == annotationIdToRemove {
          self.mapView.removeAnnotation(annotation)
      }
  
  
  }
  </code></pre></li>
  </ol>