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我正在尝试使用内置值包来序列化/反序列化数据。但是我在使用上面的包解析嵌套的 JSON 数据时遇到了困难。请帮助我在哪里进行更改，因为大多数代码是由构建运行程序自动生成的。

JSON INPUT: 
{
    "Italian": [
        {
            "name": "Item A",
            "price": 297.0,
            "stall": "380b80f4-425a-4916-b8ec-3a2ce0139d07",
        },
        {
            "name": "Item B",
            "price": 72.0,
            "stall": "380b80f4-425a-4916-b8ec-3a2ce0139d07",
        },
    ],
}

abstract class StallMenuItem
    implements Built<StallMenuItem, StallMenuItemBuilder> {
  @BuiltValueField(wireName: 'name')
  String get itemName;
  @BuiltValueField(wireName: 'price')
  num get price;
  @BuiltValueField(wireName: 'stall')
  String get stallId;

  StallMenuItem._();

  factory StallMenuItem([updates(StallMenuItemBuilder b)]) = _$StallMenuItem;
  static Serializer<StallMenuItem> get serializer => _$stallMenuItemSerializer;
}

abstract class StallMenuItemList
    implements Built<StallMenuItemList, StallMenuItemListBuilder> {
  BuiltMap<String, BuiltList<StallMenuItem>> get foodCategoryMap;

  StallMenuItemList._();

  factory StallMenuItemList([updates(StallMenuItemListBuilder b)]) =
      _$StallMenuItemList;
  static Serializer<StallMenuItemList> get serializer =>
      _$stallMenuItemListSerializer;
}

class BuiltValueConvertor extends JsonConverter {
  @override
  Response<BodyType> convertResponse<BodyType, InnerType>(Response response) {
    final Response dynamicResponse = super.convertResponse(response);
    final BodyType customBody = _convertToCustomObject<InnerType>(dynamicResponse.body);
    return dynamicResponse.replace<BodyType>(body: customBody);
  }

  dynamic _convertToCustomObject<InnerType>(dynamic element) {
    if (element is InnerType) return element;
    if (element is List)
      return _deserializeListOf<InnerType>(element);
    else
      return _deserialize<InnerType>(element);
  }

  BuiltList<InnerType> _deserializeListOf<InnerType>(
    List dynamicList,
  ) {
    return BuiltList<InnerType>(
      dynamicList.map((element) => _deserialize<InnerType>(element)),
    );
  }

  InnerType _deserialize<InnerType>(
    Map<String, dynamic> value,
  ) {
    return serializers.deserializeWith<InnerType>(
      serializers.serializerForType(InnerType),
      value,
    );
  }
}

@SerializersFor(const [StallItem, StallMenuItem, StallMenuItemList, BuiltMap])
final Serializers serializers =
    (_$serializers.toBuilder()..addPlugin(StandardJsonPlugin())).build();

我遵循了以下教程：- https://resocoder.com/2019/07/14/chopper-retrofit-for-flutter-3-converters-built-value-integration/

E/flutter (31674): [ERROR:flutter/lib/ui/ui_dart_state.cc(157)] Unhandled Exception: type 'BuiltMapSerializer' is not a subtype of type 'Serializer<BuiltMap<String, BuiltList<StallMenuItem>>>'
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1 回答 1

0 
abstract class StallMenuItemList
    implements Built<StallMenuItemList, StallMenuItemListBuilder> {
  BuiltList<StallMenuItem> get Italian;

  StallMenuItemList._();

  factory StallMenuItemList([updates(StallMenuItemListBuilder b)]) =
      _$StallMenuItemList;
  static Serializer<StallMenuItemList> get serializer =>
      _$stallMenuItemListSerializer;
}

请使用此代码。

于 2021-02-05T17:32:43.890 回答