how to create an entity based on a model? - flutter

Question

Tell me please. At first, I decided to make a simple application, but now I want to use a clean architecture and I need to know what my HomeEntity should look like. I have a model, it was generated by the site. And I also need all the fields of my model in my entity.
I can’t just use JUST all the fields that I described there, because some of them need to be “entered”
Here is my model -
// To parse this JSON data, do
//
// final plan = planFromJson(jsonString);
import 'dart:convert';
Plan planFromJson(String str) => Plan.fromJson(json.decode(str));
String planToJson(Plan data) => json.encode(data.toJson());
class Plan {
Plan({
required this.data,
required this.meta,
});
List<Datum> data;
Meta meta;
factory Plan.fromJson(Map<String, dynamic> json) => Plan(
data: List<Datum>.from(json["data"].map((x) => Datum.fromJson(x))),
meta: Meta.fromJson(json["meta"]),
);
Map<String, dynamic> toJson() => {
"data": List<dynamic>.from(data.map((x) => x.toJson())),
"meta": meta.toJson(),
};
}
class Datum {
Datum({
required this.id,
required this.attributes,
});
int id;
DatumAttributes attributes;
factory Datum.fromJson(Map<String, dynamic> json) => Datum(
id: json["id"],
attributes: DatumAttributes.fromJson(json["attributes"]),
);
Map<String, dynamic> toJson() => {
"id": id,
"attributes": attributes.toJson(),
};
}
class DatumAttributes {
DatumAttributes({
required this.header,
required this.description,
required this.added,
required this.createdAt,
required this.updatedAt,
required this.publishedAt,
required this.image,
});
String header;
String description;
bool added;
DateTime createdAt;
DateTime updatedAt;
DateTime publishedAt;
Image image;
factory DatumAttributes.fromJson(Map<String, dynamic> json) => DatumAttributes(
header: json["header"],
description: json["description"],
added: json["added"],
createdAt: DateTime.parse(json["createdAt"]),
updatedAt: DateTime.parse(json["updatedAt"]),
publishedAt: DateTime.parse(json["publishedAt"]),
image: Image.fromJson(json["image"]),
);
Map<String, dynamic> toJson() => {
"header": header,
"description": description,
"added": added,
"createdAt": createdAt.toIso8601String(),
"updatedAt": updatedAt.toIso8601String(),
"publishedAt": publishedAt.toIso8601String(),
"image": image.toJson(),
};
}
class Image {
Image({
required this.data,
});
Data data;
factory Image.fromJson(Map<String, dynamic> json) => Image(
data: Data.fromJson(json["data"]),
);
Map<String, dynamic> toJson() => {
"data": data.toJson(),
};
}
class Data {
Data({
required this.id,
required this.attributes,
});
int id;
DataAttributes attributes;
factory Data.fromJson(Map<String, dynamic> json) => Data(
id: json["id"],
attributes: DataAttributes.fromJson(json["attributes"]),
);
Map<String, dynamic> toJson() => {
"id": id,
"attributes": attributes.toJson(),
};
}
class DataAttributes {
DataAttributes({
required this.name,
required this.alternativeText,
required this.caption,
required this.width,
required this.height,
required this.formats,
required this.hash,
required this.ext,
required this.mime,
required this.size,
required this.url,
required this.previewUrl,
required this.provider,
required this.providerMetadata,
required this.createdAt,
required this.updatedAt,
});
String name;
dynamic alternativeText;
dynamic caption;
int width;
int height;
Formats formats;
String hash;
Ext? ext;
Mime? mime;
double size;
String url;
dynamic previewUrl;
String provider;
dynamic providerMetadata;
DateTime createdAt;
DateTime updatedAt;
factory DataAttributes.fromJson(Map<String, dynamic> json) => DataAttributes(
name: json["name"],
alternativeText: json["alternativeText"],
caption: json["caption"],
width: json["width"],
height: json["height"],
formats: Formats.fromJson(json["formats"]),
hash: json["hash"],
ext: extValues.map[json["ext"]],
mime: mimeValues.map[json["mime"]],
size: json["size"].toDouble(),
url: json["url"],
previewUrl: json["previewUrl"],
provider: json["provider"],
providerMetadata: json["provider_metadata"],
createdAt: DateTime.parse(json["createdAt"]),
updatedAt: DateTime.parse(json["updatedAt"]),
);
Map<String, dynamic> toJson() => {
"name": name,
"alternativeText": alternativeText,
"caption": caption,
"width": width,
"height": height,
"formats": formats.toJson(),
"hash": hash,
"ext": extValues.reverse[ext],
"mime": mimeValues.reverse[mime],
"size": size,
"url": url,
"previewUrl": previewUrl,
"provider": provider,
"provider_metadata": providerMetadata,
"createdAt": createdAt.toIso8601String(),
"updatedAt": updatedAt.toIso8601String(),
};
}
enum Ext { JPG }
final extValues = EnumValues({
".jpg": Ext.JPG
});
class Formats {
Formats({
required this.thumbnail,
required this.small,
required this.medium,
required this.large,
});
Small thumbnail;
Small small;
Small? medium;
Small? large;
factory Formats.fromJson(Map<String, dynamic> json) => Formats(
thumbnail: Small.fromJson(json["thumbnail"]),
small: Small.fromJson(json["small"]),
medium: json["medium"] == null ? null : Small.fromJson(json["medium"]),
large: json["large"] == null ? null : Small.fromJson(json["large"]),
);
Map<String, dynamic> toJson() => {
"thumbnail": thumbnail.toJson(),
"small": small.toJson(),
"medium": medium == null ? null : medium?.toJson(),
"large": large == null ? null : large?.toJson(),
};
}
class Small {
Small({
required this.name,
required this.hash,
required this.ext,
required this.mime,
required this.path,
required this.width,
required this.height,
required this.size,
required this.url,
});
String name;
String hash;
Ext? ext;
Mime? mime;
dynamic path;
int width;
int height;
double size;
String url;
factory Small.fromJson(Map<String, dynamic> json) => Small(
name: json["name"],
hash: json["hash"],
ext: extValues.map[json["ext"]],
mime: mimeValues.map[json["mime"]],
path: json["path"],
width: json["width"],
height: json["height"],
size: json["size"].toDouble(),
url: json["url"],
);
Map<String, dynamic> toJson() => {
"name": name,
"hash": hash,
"ext": extValues.reverse[ext],
"mime": mimeValues.reverse[mime],
"path": path,
"width": width,
"height": height,
"size": size,
"url": url,
};
}
enum Mime { IMAGE_JPEG }
final mimeValues = EnumValues({
"image/jpeg": Mime.IMAGE_JPEG
});
class Meta {
Meta({
required this.pagination,
});
Pagination pagination;
factory Meta.fromJson(Map<String, dynamic> json) => Meta(
pagination: Pagination.fromJson(json["pagination"]),
);
Map<String, dynamic> toJson() => {
"pagination": pagination.toJson(),
};
}
class Pagination {
Pagination({
required this.page,
required this.pageSize,
required this.pageCount,
required this.total,
});
int page;
int pageSize;
int pageCount;
int total;
factory Pagination.fromJson(Map<String, dynamic> json) => Pagination(
page: json["page"],
pageSize: json["pageSize"],
pageCount: json["pageCount"],
total: json["total"],
);
Map<String, dynamic> toJson() => {
"page": page,
"pageSize": pageSize,
"pageCount": pageCount,
"total": total,
};
}
class EnumValues<T> {
Map<String, T> map;
late Map<T, String> reverseMap;
EnumValues(this.map);
Map<T, String> get reverse {
if (reverseMap == null) {
reverseMap = map.map((k, v) => new MapEntry(v, k));
}
return reverseMap;
}
}
It will be cool if you help me create an entity for this model and explain the principle of how I can create it myself

Answer 1

define your class and its fields like this case:
class MobileViewModel {
final String countryCallingCode;
final String mobileNumber;
}
define the constructor of your class like this:
MobileViewModel({
required this.countryCallingCode,
required this.mobileNumber,
});
if you needs optional fields just remove requierd keyword and make your fields nullable.
then write fromJson method as a factory constructor.
(factory constructor returns an instance of your class from a json.)
factory MobileViewModel.fromJson(final Map<String, dynamic> json) =>
MobileViewModel(
countryCallingCode: json['countryCallingCode'],
mobileNumber: json['mobileNumber'],
);