MultiPolygon.fromJson constructor Null safety
Creates a MultiPolygon from a GeoJSON Map.
Example:
MultiPolygon.fromJson({'type': 'Feature', 'geometry': {'type': 'MultiPolygon', 'coordinates': [[[[1, 2], [3, 4], [5, 6], [1, 2]]], [[[7, 8], [9, 10], [11, 12], [7, 8]]]]}, 'properties': {}}); // MultiPolygon([[LinearRing([Coordinate(1, 2), Coordinate(3, 4), Coordinate(5, 6), Coordinate(1, 2)]), LinearRing([Coordinate(7, 8), Coordinate(9, 10), Coordinate(11, 12), Coordinate(7, 8)])]])
Implementation
@override
factory MultiPolygon.fromJson(Map<String, dynamic> json) {
if (json['geometry']['type'] != 'MultiPolygon') {
throw ArgumentError('json is not a MultiPolygon');
}
return MultiPolygon(
(json['geometry']['coordinates'] as List<List<List<List<double>>>>)
.map((dynamic poly) => (poly as List<List<List<double>>>)
.map((dynamic shape) => LinearRing((shape as List<List<double>>)
.map((dynamic coord) => Coordinate.fromJson(coord))
.toList()))
.toList())
.toList(),
properties: Map<String, dynamic>.from(json['properties']),
);
}