Flutter - Isar schema is not defined

Question

I have decided to use Isar database in my next project and I find it much helpful when dealing with local data.

I followed the quickstart guide in its website. I added dependencies. Annotated the contact class. Ran code generator. But at fourth step, I have problem creating schema while creating Isar instance.

initIsar() async {
  final dir = await getApplicationSupportDirectory();
  final isar = await Isar.open(
    schemas: [ContactSchema],
    directory: dir.path,
    inspector: true,
  );
}

The problem is where I typed ContactSchema, it says

Undefined name 'ContactSchema'.
Try correcting the name to one that is defined, or defining the name.

So question I have to ask is, I followed guide but I'm unable to create a schema. How can I create one to make Isar db work?

UPDATE:

import 'package:isar/isar.dart';

part 'contact.g.dart';

@Collection()
class Contact {
  @Id()
  int? id;

  late String name;
}

After adding part 'contact.g.dart', type this command flutter pub run build_runner build and you are good to go.

Answer 1

For completeness of response:

Run (error? look at it, it likely say to remove isar from the first command)

flutter pub add isar isar_flutter_libs
flutter pub add -d isar_generator build_runner
flutter pub run build_runner build # Run every update of the collection

Example collection:

@Collection(accessor: "time")
class Timer {
  final Id id = Isar.autoIncrement;

  @Index(
    unique: true,
    replace: true,
  )
  late final bool isRunning;
  late final DateTime dates = DateTime.now();
}

Suggestion: (tree -x output)

$ tree -x
.
├── main.dart
└── model
    ├── timer.dart
    └── timer.g.dart

1 directory, 3 files

For how I'm using this:

void main() async {
  // ignore: unused_local_variable
  final isar = await Isar.open([TimerSchema]);
  runApp(const MyApp());
}