Flutter Hive store color

Question

I need to store colour in my Hive database to retrieve in my eCommerce Application, it gave me the error below saying that I need to make an adapter, can anyone tell me how to make a colour adapter?

part 'items_model.g.dart';

@HiveType(typeId: 0)
class Item {
  @HiveField(0)
  final String name;
  @HiveField(1)
  final double price;
  @HiveField(2)
  final String? description;
  @HiveField(3)
  var image;
  @HiveField(4)
  final String id;
  @HiveField(5)
  final String shopName;
  @HiveField(6)
  final List<Category> category;
  @HiveField(7)
  Color? color;
  @HiveField(8)
  int? quantity;
  Item({
    required this.category,
    required this.image,
    required this.name,
    required this.price,
    this.description,
    required this.id,
    required this.shopName,
    this.color,
    required this.quantity,
  });



}

does anyone know how to generate or create Color Adapter? as I don't know-how

E/flutter ( 4621): [ERROR:flutter/lib/ui/ui_dart_state.cc(209)] Unhandled Exception: HiveError: Cannot write, unknown type: MaterialColor. Did you forget to register an adapter?

Answer 1

I think the easiest thing to do here would be to store the int value of the color.

Here's an example.

final colorValue = Colors.blue.value; // colorValue is an integer here

So your Hive color could be stored like this

@HiveField(7)
int? colorValue;

Then, in your app when you're creating a color from storage it would look like this.

final item = Item(...however you initialize your Item);

final color = Color(item.colorValue);

Answer 2

Base on previous answers by @Cryptozord and @Loren.A one can simply just write specific adapter for color

import 'package:flutter/cupertino.dart';
import 'package:hive/hive.dart';

class ColorAdapter extends TypeAdapter<Color> {
  @override
  final typeId = 221;

  @override
  Color read(BinaryReader reader) => Color(reader.readUint32());

  @override
  void write(BinaryWriter writer, Color obj) => writer.writeUint32(obj.value);
}

and remember to register your adapter with

Hive.registerAdapter(ColorAdapter());

make sure your typeId is not taken by other models

now you can use

@HiveField(7)
Color? colorValue;