Default value within the `HiveField` annotation

[pro100svitlo]

Hi!

Have an idea how the default values can be set in easy way for TypeAdapter. All we need - add new field to HiveField annotation and then use it during class generation.

class HiveField {
  final int index;
  final dynamic defaultValue;
  const HiveField(this.index, {this.defaultValue});
}

Then in our class we can do like this:

@HiveType()
class CityHive {
  @HiveField(0, defaultValue: -1)
  int id;
  @HiveField(1, defaultValue: "Some name")
  String name;
  @HiveField(2)
  double lat;
  @HiveField(3)
  double lng;
}

Generated class will looks like this:

class CityHiveAdapter extends TypeAdapter<CityHive> {
  @override
  CityHive read(BinaryReader reader) {
    var numOfFields = reader.readByte();
    var fields = <int, dynamic>{
      for (var i = 0; i < numOfFields; i++) reader.readByte(): reader.read(),
    };
    return CityHive()
      ..id = fields[0] as int ?? -1
      ..name = fields[1] as String ?? "Some name"
      ..lat = fields[2] as double
      ..lng = fields[3] as double
  }
  ...
}