fromData<R extends FeatureObject, E extends Geometry> static method

R fromData<R extends FeatureObject, E extends Geometry>(Map<String, dynamic> data, { TextReaderFormat<FeatureContent> format = GeoJSON.feature, CoordRefSys? crs, Map<String, dynamic>? options, })

Decode a feature object of R from data conforming to format.

Data should be a JSON Object as decoded by the standard json.decode().

When format is not given, then the feature format of GeoJSON is used as a default.

Use crs to give hints (like axis order, and whether x and y must be swapped when read in) about coordinate reference system in text input.

Format or decoder implementation specific options can be set by options.

Implementation

static R fromData<R extends FeatureObject, E extends Geometry>(
  Map<String, dynamic> data, {
  TextReaderFormat<FeatureContent> format = GeoJSON.feature,
  CoordRefSys? crs,
  Map<String, dynamic>? options,
}) {
  R? result;

  // get feature builder to build a feature object of R
  final builder = FeatureBuilder<R, E>._((object, {name}) {
    if (result != null) {
      throw const FormatException('Already decoded one');
    }
    result = object;
  });

  // get decoder with the content decoded sent to builder
  final decoder = format.decoder(
    builder,
    crs: crs,
    options: options,
  );

  // decode and return result if succesful
  decoder.decodeData(data);
  if (result != null) {
    return result!;
  } else {
    throw const FormatException('Could not decode text');
  }
}