Other Protocols

The following protocols are available globally.

  • A protocol that feature subclasses (i.e. those already conforming to the MGLFeature protocol) conform to if they represent clusters.

    Currently the only class that conforms to MGLCluster is MGLPointFeatureCluster (a subclass of MGLPointFeature).

    To check if a feature is a cluster, check conformity to MGLCluster, for example:

    let shape = try! MGLShape(data: clusterShapeData, encoding: String.Encoding.utf8.rawValue)
    
    guard let pointFeature = shape as? MGLPointFeature else {
        throw ExampleError.unexpectedFeatureType
    }
    
    // Check for cluster conformance
    guard let cluster = pointFeature as? MGLCluster else {
        throw ExampleError.featureIsNotACluster
    }
    
    // Currently the only supported class that conforms to `MGLCluster` is
    // `MGLPointFeatureCluster`
    guard cluster is MGLPointFeatureCluster else {
        throw ExampleError.unexpectedFeatureType
    }
    
    See more

    Declaration

    Objective-C

    @protocol MGLCluster <MGLFeature>

    Swift

    protocol MGLCluster
  • Data source for MGLComputedShapeSource. This protocol defines two optional methods for fetching data, one based on tile coordinates, and one based on a bounding box. Classes that implement this protocol must implement one, and only one of the methods. Methods on this protocol will not be called on main thread, they will be called on the caller’s requestQueue.

    See more

    Declaration

    Objective-C

    @protocol MGLComputedShapeSourceDataSource <NSObject>

    Swift

    protocol MGLComputedShapeSourceDataSource : NSObjectProtocol
  • The MGLObservable protocol declares methods that conforming classes should implement should they want to observe low-level events of type MGLEvent. Currently only MGLMapView implements MGLObservable.

    See more

    Declaration

    Objective-C

    @protocol MGLObservable

    Swift

    protocol MGLObservable
  • The MGLOfflineStorageDelegate protocol defines methods that a delegate of an MGLOfflineStorage object can optionally implement to transform various types of URLs before downloading them via the internet.

    See more

    Declaration

    Objective-C

    @protocol MGLOfflineStorageDelegate <NSObject>

    Swift

    protocol MGLOfflineStorageDelegate : NSObjectProtocol