FieldInstance.fromJson constructor
      
      FieldInstance.fromJson()
     
    
    
Implementation
factory FieldInstance.fromJson(
  Map<String, dynamic> json,
  Map<String, FieldPrototype> fieldPrototypes,
  Map<String, DataHandler> dataHandlers,
) {
  if (!fieldPrototypes.containsKey(json['idName'].toString())) {
    throw Exception('Field prototype not found');
  }
  final prototype = fieldPrototypes[json['idName'].toString()]!;
  return FieldInstance(
    prototype: prototype,
    data: json['data'] != 'null'
        ? dataHandlers[prototype.dataType.toString()]?.fromJson(json['data'])
        : null,
  );
}