Annotation controllers

An MGLStyleAnnotationController is the object responsible for adding, removing, and updating MGLStyleAnnotations on a map.

Do not create instances of MGLStyleAnnotationController directly. Instead, create an instance of MGLCircleAnnotationController, MGLLineAnnotationController, MGLPolygonAnnotationController, or MGLSymbolAnnotationController and use -[MGLAnnotationController addShape:] or -[MGLStyleAnnotationController addShapes:] to add shapes to an MGLMapView.

An MGLCircleAnnotationController is a controller that creates internally instances of an MGLShapeSource and MGLCicleStyleLayer to simplify the creation of runtime styling based annotations to the map.

Create instances of MGLCircleStyleAnnotation and pass it to this controller to add circular shapes to an MGLMapView.

Example

func mapView(_ mapView: MGLMapView, didFinishLoading style: MGLStyle) {
   let circleAnnotationController = MGLCircleAnnotationController(mapView: self.mapView)
   let circle = MGLCircleStyleAnnotation(center: CLLocationCoordinate2D(latitude: 59.31, longitude: 18.06), radius: 3.0, color: .blue)
   circle.opacity = 0.5
   circleAnnotationController.add(circle)
}

An MGLLineAnnotationController is a controller that creates internally instances of an MGLShapeSource and MGLLineStyleLayer to simplify the creation of runtime styling based annotations to the map.

Create instances of MGLLineStyleAnnotation and pass it to this controller.

Example

func mapView(_ mapView: MGLMapView, didFinishLoading style: MGLStyle) {
   let lineAnnotationController = MGLLineAnnotationController(mapView: self.mapView)

   let lineCoordinates = [
       CLLocationCoordinate2D(latitude: 59, longitude: 18),
       CLLocationCoordinate2D(latitude: 60, longitude: 20)
   ]

   let line = MGLLineStyleAnnotation(coordinates: lineCoordinates, count: UInt(lineCoordinates.count))
   line.color = .purple
   lineAnnotationController.add(line)
}

An MGLPolygonAnnotationController is a controller that creates internally instances of an MGLShapeSource and MGLFillStyleLayer to simplify the creation of runtime styling based annotations to the map.

Create instances of MGLPolygonStyleAnnotation and pass it to this controller.

Example

func mapView(_ mapView: MGLMapView, didFinishLoading style: MGLStyle) {
   let polygonAnnotationController = MGLPolygonAnnotationController(mapView: self.mapView)

   let polygonCoordinates = [
       CLLocationCoordinate2DMake(59, 18),
       CLLocationCoordinate2DMake(62, 19),
       CLLocationCoordinate2DMake(54, 20),
       CLLocationCoordinate2DMake(59, 18)
   ]

   let polygon = MGLPolygonStyleAnnotation(coordinates: polygonCoordinates, count: UInt(polygonCoordinates.count))
   polygon.fillOutlineColor = .red
   polygonAnnotationController.add(polygon)
}

An MGLSymbolAnnotationController is a controller that creates internally instances of an MGLShapeSource and MGLSymbolStyleLayer to simplify the creation of runtime styling based annotations to the map.

Create instances of MGLSymbolStyleAnnotation and pass it to this controller.

An image must be supplied to the map style’s sprite before being able to assign it to be the icon image of a symbol.

Example

func mapView(_ mapView: MGLMapView, didFinishLoading style: MGLStyle) {
   let attraction = UIImage(named: "attraction")

   if let styleImage = attraction {
       self.mapView.style?.setImage(styleImage, forName: "attraction")
   }

   let symbolAnnotationController = MGLSymbolAnnotationController(mapView: self.mapView)

   let symbol = MGLSymbolStyleAnnotation(coordinate: CLLocationCoordinate2DMake(59, 18));
   symbol.iconImageName = "attraction"
   symbol.text = "This is a cool place!"
   symbol.textFontSize = 16
   symbolAnnotationController.add(symbol)
}