getBoundingBox method

@override Future<BoundingBox> getBoundingBox()

Returns the geographic area covered by this datastore.

Returns the bounding box defining the extent of available map data

Implementation

@override
Future<BoundingBox> getBoundingBox() async {
  if (_boundingBox != null) return _boundingBox!;
  final List<Datastore> datastoresList = datastores.toList();

  // Fetch all boundaries in parallel, using the cache when available.
  final List<Future<BoundingBox>> futures = [];
  for (Datastore datastore in datastoresList) {
    BoundingBox? boundingBox = _datastoreBoundaries[datastore];
    futures.add(boundingBox != null ? Future.value(boundingBox) : datastore.getBoundingBox());
  }
  final List<BoundingBox> boundaries = await Future.wait(futures);

  for (int i = 0; i < datastoresList.length; ++i) {
    Datastore datastore = datastoresList[i];
    BoundingBox boundingBox = boundaries[i];
    _datastoreBoundaries[datastore] = boundingBox;

    if (null == _boundingBox) {
      _boundingBox = boundingBox;
    } else {
      _boundingBox = _boundingBox!.extendBoundingBox(boundingBox);
    }
  }
  return _boundingBox!;
}