geoxml

A Dart library for loading, manipulating, and saving GPS data in XML format, including GPX and KML.

GPX is a light-weight XML data format for the interchange of GPS data - waypoints, routes, and tracks. KML is a XML data format used to display geographic data in an Earth browser such as Google Earth.

The GPX document: https://www.topografix.com/gpx.asp. And for KML, see https://developers.google.com/kml/ .

The project is originally authored by @kb0 with others, thanks for their works.

Limitations

This is just an initial version of the package. There are still some limitations:

• No support for GPX 1.0.
• Doesn't validate schema declarations.
• Some KML elements and attributes are not implemented.
• The conversion between GPX and KML is lossy. For example, GPX does not contain style information such as color, while KML can not tell the difference between routes and tracks. Converting a GPX to KML and then converting it back cannot obtain the original GPX.

Getting Started

In your dart/flutter project add the dependency:

 dependencies:
   ...
   geoxml: ^2.5.3

Reading GPX

To read GPX input use the GpxReader object and function GeoXml.fromGpxString(String input):

import 'package:geoxml/geoxml.dart';

main() async {
  // create gpx from xml string
  var xmlGpx = await GeoXml.fromGpxString('<?xml version="1.0" encoding="UTF-8"?>'
      '<gpx version="1.1" creator="dart-gpx library">'
      '<wpt lat="-25.7996" lon="-62.8666"><ele>10.0</ele><name>Monte Quemado</name><desc>Argentina</desc></wpt>'
      '</gpx>');

  print(xmlGpx);
  print(xmlGpx.wpts);
}

To read GPX from a Stream<String>:

import 'package:geoxml/geoxml.dart';

main() async {
  // create gpx from xml string stream
  final stream = File('test/assets/wpt.gpx').openRead()
      .transform(utf8.decoder);
  final xmlGpx = await GeoXml.fromGpxStream(stream);

  print(xmlGpx);
  print(xmlGpx.wpts);
}

Writing GPX

To write object to GPX use the method asGpxString(Gpx gpx, {bool pretty = false}):

import 'package:geoxml/geoxml.dart';

main() {
  // create gpx object
  var gpx = Gpx();
  gpx.creator = "dart-gpx library";
  gpx.wpts = [
    Wpt(lat: 36.62, lon: 101.77, ele: 10.0, name: 'Xining', desc: 'China'),
  ];

  // generate xml string
  var gpxString = gpx.asGpxString(pretty: true);
  print(gpxString);
}

Reading KML

To read KML input use the KmlReader object and function GeoXml.fromKmlString(String input):

import 'package:geoxml/geoxml.dart';

main() async {
  // create gpx from xml string
  var xmlKml = await GeoXml.fromKmlString('<?xml version="1.0" encoding="UTF-8"?> '
      '<kml xmlns="http://www.opengis.net/kml/2.2"><Document><Placemark><name>Monte Quemado</name>'
      '<description>Argentina</description> <ExtendedData/>'
      '<Point><altitudeMode>absolute</altitudeMode>'
      '<coordinates>-62.8666,-25.7996,10.0</coordinates></Point></Placemark>'
      '</Document></kml>');

  print(xmlKml);
  print(xmlKml.wpts);
}

To read KML from a Stream<String>:

import 'package:geoxml/geoxml.dart';

main() async {
  // create gpx from xml string stream
  final stream = File('test/assets/wpt.kml').openRead()
      .transform(utf8.decoder);
  final kml = await GeoXml.fromKmlStream(stream);

  print(xmlGpx);
  print(xmlGpx.wpts);
}

Writing KML

To export object to KML use the method asKmlString({bool pretty = false}):

import 'package:geoxml/geoxml.dart';

main() {
  // create gpx object
  var geoXml = GeoXml();
  geoXml.creator = "dart geoxml library";
  geoXml.wpts = [
    Wpt(lat: 36.62, lon: 101.77, ele: 10.0, name: 'Xining', desc: 'China'),
  ];

  // generate xml string
  var kmlString = geoXml.asKmlString(pretty: true);
  print(kmlString);

  // generate xml string with altitude mode - clampToGround
  var kmlString = KmlWriter(altitudeMode: AltitudeMode.clampToGround)
      .asString(gpx, pretty: true);
  print(kmlString);
}

Features and bugs

Please file feature requests and bugs at the issue tracker.

License

The Apache 2.0 License, see LICENSE.