# MGLAnnotation

    @protocol MGLAnnotation <NSObject>

The `MGLAnnotation` protocol is used to provide annotation-related information to a map view. To use this protocol, you adopt it in any custom objects that store or represent annotation data. Each object then serves as the source of information about a single map annotation and provides critical information, such as the annotation’s location on the map. Annotation objects do not provide the visual representation of the annotation but typically coordinate (in conjunction with the map view’s delegate) the creation of an appropriate objects to handle the display.

An object that adopts this protocol must implement the `coordinate` property. The other methods of this protocol are optional.

#### Related examples

See the Annotation models and Annotation views examples to learn how to add objects that follow the `MGLAnnotation` protocol.

### Position Attributes

- `coordinate`

  The center point (specified as a map coordinate) of the annotation. (required) (read-only)

  #### Declaration

  Objective-C

      @property (readonly, nonatomic) CLLocationCoordinate2D coordinate;

  Swift

      var coordinate: CLLocationCoordinate2D { get }

  View Source on GitHub

### Title Attributes

- `title`

  The string containing the annotation’s title.

  Although this property is optional, if you support the selection of annotations in your map view, you are expected to provide this property. This string is displayed in the callout for the associated annotation.

  #### Declaration

  Objective-C

      @optional
      @property (readonly, copy, nonatomic, nullable) NSString *title;

  Swift

      optional var title: String? { get }

  View Source on GitHub
- `subtitle`

  The string containing the annotation’s subtitle.

  This string is displayed in the callout for the associated annotation.

  #### Declaration

  Objective-C

      @optional
      @property (readonly, copy, nonatomic, nullable) NSString *subtitle;

  Swift

      optional var subtitle: String? { get }

  View Source on GitHub