Unhandled Exception: HiveError: Cannot write, unknown type: _File. Did you forget to register an adapter?

Question

I use model of places where I have File object to store the path of images taken by device camera.

I want to store File(image.path) in Hive. But I get :

part 'place.g.dart';

@HiveType(typeId: 0)
class Place extends HiveObject {
  @HiveField(0)
  final String id;

  @HiveField(1)
  final String name;

  @HiveField(2)
  final File image;

  @HiveField(3)
  final Location? location;

  Place(this.id, this.name, this.image, this.location);
}


    part 'file.g.dart';

@HiveType(typeId: 1)
class ImageFile extends HiveObject {
  @HiveField(3)
  File file;
  ImageFile(this.file);
}

I have initialized and registered the adapters as well.

  final dir = await getApplicationDocumentsDirectory();
  Hive.init(dir.path);
  Hive.registerAdapter(PlaceAdapter());
  Hive.registerAdapter(LocationAdapter());
  Hive.registerAdapter(ImageFileAdapter());```


 Hive docs recommends to write your own TypeAdapter for other types other than primitive ones?

But I don't have an idea how to write TypeAdapter for File

thx

user_10300300 · Answer

I resolved the issue by converting File to Uint8List which is a primitive type supported by Hive.

So when I store a File(image.path) I add it by pickedImage.readAsBytesSync();

and when I read an image from hive box I use Image.memory();

I don't know it is solution or not, but it worked for me.

Unhandled Exception: HiveError: Cannot write, unknown type: _File. Did you forget to register an adapter?

1 Answers