Event Handlers

Map event handlers are passed to each provider-specific map view initializer. They are not SwiftUI view modifiers.

GoogleMapView(
    state: mapViewState,
    onMapLoaded: { state in
        print("Loaded: \(state.id)")
    },
    onMapClick: { point in
        print("Clicked: \(point.latitude), \(point.longitude)")
    },
    onCameraMoveStart: { camera in
        print("Move started: \(camera.zoom)")
    },
    onCameraMove: { camera in
        print("Moving: \(camera.position)")
    },
    onCameraMoveEnd: { camera in
        print("Move ended: \(camera.zoom)")
    }
) {
    Marker(
        position: GeoPoint(latitude: 35.6812, longitude: 139.7671),
        onClick: { marker in
            print("Marker clicked: \(marker.id)")
        }
    )
}

The same initializer arguments are available on GoogleMapView, MapboxMapView, MapKitMapView, MapLibreMapView, and ArcGISMapView.

Marker Events

Marker and MarkerState support these handlers:

• onClick: (MarkerState) -> Void
• onDragStart: (MarkerState) -> Void
• onDrag: (MarkerState) -> Void
• onDragEnd: (MarkerState) -> Void
• onAnimateStart: (MarkerState) -> Void
• onAnimateEnd: (MarkerState) -> Void

Marker(
    position: GeoPoint(latitude: 35.6812, longitude: 139.7671),
    draggable: true,
    onClick: { state in
        print("Clicked marker \(state.id)")
    },
    onDragEnd: { state in
        print("Dropped at \(state.position)")
    }
)

Shape Events

Shape click handlers are configured on the overlay or state initializer:

Circle(
    center: GeoPoint(latitude: 35.6812, longitude: 139.7671),
    radiusMeters: 500,
    onClick: { event in
        print("Circle clicked at \(event.clicked)")
    }
)

Polyline(
    points: route,
    onClick: { event in
        print("Polyline clicked at \(event.clicked)")
    }
)

Polygon(
    points: polygon,
    onClick: { event in
        print("Polygon clicked at \(event.clicked)")
    }
)

GroundImage also has onClick: (GroundImageEvent) -> Void. RasterLayerState defines a RasterLayerEvent type, but RasterLayer itself does not expose an onClick initializer.