Extended Data
@Serializable
The ExtendedData element offers three techniques for adding custom data to a KML Feature (NetworkLink, Placemark, GroundOverlay, PhotoOverlay, ScreenOverlay, Document, Folder).
These techniques are:
Adding untyped data/value pairs using the element (basic)
Declaring new typed fields using the
element and then instancing them using the element (advanced) Referring to XML elements defined in other namespaces by referencing the external namespace within the KML file (basic)
These techniques can be combined within a single KML file or Feature for different pieces of data. For more information, see Adding Custom Data in "Topics in KML."