GroupNode<T>.fromJson constructor

GroupNode<T>.fromJson(
  1. Map<String, dynamic> json, {
  2. required T dataFromJson(
    1. Object? json
    ),
})

Creates a GroupNode from a JSON map.

This factory constructor is used during workflow deserialization to recreate group nodes from saved data.

Parameters:

  • json - The JSON map containing node data
  • dataFromJson - Function to deserialize the custom data of type T

Implementation

factory GroupNode.fromJson(
  Map<String, dynamic> json, {
  required T Function(Object? json) dataFromJson,
}) {
  // Parse padding from JSON (stored as LTRB array or object)
  EdgeInsets padding = kGroupNodeDefaultPadding;
  final paddingJson = json['padding'];
  if (paddingJson != null) {
    if (paddingJson is List) {
      padding = EdgeInsets.fromLTRB(
        (paddingJson[0] as num).toDouble(),
        (paddingJson[1] as num).toDouble(),
        (paddingJson[2] as num).toDouble(),
        (paddingJson[3] as num).toDouble(),
      );
    } else if (paddingJson is Map) {
      padding = EdgeInsets.fromLTRB(
        (paddingJson['left'] as num?)?.toDouble() ?? 0,
        (paddingJson['top'] as num?)?.toDouble() ?? 0,
        (paddingJson['right'] as num?)?.toDouble() ?? 0,
        (paddingJson['bottom'] as num?)?.toDouble() ?? 0,
      );
    }
  }

  // Parse ports
  final inputPorts =
      (json['inputPorts'] as List<dynamic>?)
          ?.map((e) => Port.fromJson(Map<String, dynamic>.from(e as Map)))
          .toList() ??
      const [];
  final outputPorts =
      (json['outputPorts'] as List<dynamic>?)
          ?.map((e) => Port.fromJson(Map<String, dynamic>.from(e as Map)))
          .toList() ??
      const [];

  return GroupNode<T>(
    id: json['id'] as String,
    position: Offset(
      (json['x'] as num).toDouble(),
      (json['y'] as num).toDouble(),
    ),
    size: Size(
      (json['width'] as num?)?.toDouble() ?? 200.0,
      (json['height'] as num?)?.toDouble() ?? 150.0,
    ),
    title: json['title'] as String? ?? '',
    data: dataFromJson(json['data']),
    color: Color(json['color'] as int? ?? Colors.blue.toARGB32()),
    behavior: GroupBehavior.values.byName(
      json['behavior'] as String? ?? 'bounds',
    ),
    nodeIds: (json['nodeIds'] as List<dynamic>?)
        ?.map((e) => e as String)
        .toSet(),
    padding: padding,
    zIndex: json['zIndex'] as int? ?? -1,
    isVisible: json['isVisible'] as bool? ?? true,
    locked: json['locked'] as bool? ?? false,
    inputPorts: inputPorts,
    outputPorts: outputPorts,
  );
}