title: iOS annotationView is not dragging when there are multiple annotationView are near by?
body: <p>I have a map view, on map view there are multiple annotation are there and one special annotation(Add Place) is also there to add new annotation on map by dragging annotation(Add Place). "Add Place" annotation is working fine when there is no annotation under/over "Add Place" annotation but when there are annotation under/over "Add Place" annotation and I try to drag "Add Place" annotation it is not working and other annotation become active. Image will explain this better.</p>
  
  <p><a href="https://i.stack.imgur.com/OgCNL.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/OgCNL.gif" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/0Nspb.gif" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/0Nspb.gif" alt="enter image description here"></a></p>
  
  <p>Code for dragging</p>
  
  <pre><code>func mapView(_ mapView: MKMapView, annotationView view: MKAnnotationView, didChange newState: MKAnnotationViewDragState, fromOldState oldState: MKAnnotationViewDragState) {
          switch newState {
          case .starting:
              view.dragState = .dragging
              print("start")
          case .ending, .canceling:
              view.dragState = .none
              print("end")
  
              // Code to open Add new Annotation
  
          default: break
          }
      }
  </code></pre>
  
  <p>I used this code to code to make annotation("Add Place") on top of all other annotation</p>
  
  <pre><code>func mapView(_ mapView: MKMapView, didAdd views: [MKAnnotationView]) {
          for annotationView in views {
              if(!(annotationView.annotation is MKUserLocation) &amp;&amp; annotation != nil)
              {
                  if(annotationView.annotation as! CustomPointAnnotation == annotation )
                  {
                      annotationView.layer.zPosition = 999
                  }
                  else
                  {
                      annotationView.layer.zPosition = 100
                  }
              }
          }
      }
  </code></pre>