Display overlays

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Overlays are used to provide enhanced, layered information that adds contextual value to a base map, offering users dynamic, interactive, and customized data that can be visualized on top of other map elements.

Disabling overlays

Overlays can be disabled either by applying a predefined, custom map style created in Magic Lane Map Studio—where certain overlays are already disabled—or by using the disableOverlay method, as shown below:

GemError error = OverlayService.disableOverlay(CommonOverlayId.publicTransport.id);

Passing -1 (default value) as the optional categUid parameter indicates that we want to disable the entire public transport overlay, rather than targeting a specific category.

The error returned will be success if the overlay was disabled or notFound if no overlay (or overlay category) with the specified ID was found in the applied style.

To disable specific overlays within a category, you'll need to retrieve their unique identifiers (uid) as shown below:

final Completer<GemError> completer = Completer<GemError>();
final availableOverlays = OverlayService.getAvailableOverlays(onCompleteDownload: (error) {
  completer.complete(error);
});

await completer.future;
  
final collection = availableOverlays.first;
final overlayInfo = collection.getOverlayAt(0);
if(overlayInfo != null) {
  final uid = overlayInfo.uid;
  final err = OverlayService.disableOverlay(uid);
  showSnackbar(err.toString());
}

Enabling overlays

In a similar way, the overlay can be enabled using the enableOverlay method by providing the overlay id. It also has an optional categUid parameter, which when left as default, it activates whole overlay rather than a specific category.