whereWithinKilometers method
Add a proximity based constraint for finding objects with key point values near the point given and within the maximum distance given.
Implementation
void whereWithinKilometers(String key, ParseGeoPoint point, num maxDistance) {
Map<String, dynamic> condition = Map();
condition["\$nearSphere"] = point;
condition["\$maxDistanceInKilometers"] = maxDistance;
_where.putIfAbsent(key, () => parseEncoder.encode(condition));
}