deserialize method

Implementation

@override
void deserialize(XmlElement? xml)
{
  if (xml == null) return;

  // deserialize
  super.deserialize(xml);

  latitude    = Xml.get(node: xml, tag: 'latitude');
  longitude   = Xml.get(node: xml, tag: 'longitude');

  // remove datasource listener. The parent map will take care of this.
  if ((datasource != null) && (scope != null) && (scope!.datasources.containsKey(datasource))) scope!.datasources[datasource!]!.remove(this);
}