Domain Driven Design (DDD) with Firebase

Class 20 : Placeholder Note Cards

firebase store snapshot

problems i've faced

1. Missing yield* at stream functions in note_repositories.dart file

2. Changing from

           'todo':todo

   to

    'todos': instance.todos?.map((e) => e.toJson()).toList()

   todo_dtos.g.dart

3. The reason was that I has only 1 todos in my note, and I manually set this todo as a map instead of list of map. So , make sure your todos field is first an list and then enter each todo element as a map. That should solve the problem.

Class 24: Note Form Page

When I pressed update (blank screen checkbox) I've got an error says

Unhandled Exception: Unhandled error Invalid argument: Instance of '_$_TodoItemDto' occurred in Instance of 'NoteFormBloc'.

and When I pressed create (Blank screen checkbox access from floating action button) it says

Unhandled Exception: Unhandled error type 'Right<ValueFailure<dynamic>, Unit>' is not a subtype of type 'Either<ValueFailure<String>, Unit>' of 'next' occurred in Instance of 'NoteFormBloc'.

:::::::::..... Edited ......:::::::::::

(1) Update error solved: in note_dtos.g.dart , we have to iterate each todos , by default code generation unable to make that. So, by hand we have to change

'todos' : instance.todos    ->      'todos': instance.todos?.map((e) => e?.toJson())?.toList(),

(2) Create error solved: In domain/core/value_objects.dart ,

instead of writting

  return value.fold(
    (l) => left(l),
    (r) => right(unit),
  );
}

replace it with 'Left' and "Right' . Make sure it is capital..

  Either<ValueFailure<dynamic>, Unit> get failureOrUnit {
    return value.fold(
      (l) => Left(l),
      (r) => Right(unit),
    );
  }

Left returns a result of Left<ValueFailure, Unit> which is already patched value.

But, left returns a result of whole Either<L, R> left<L, R>(L l) type that means we have to patch the value by hand. And when it is dynamic value it can't work the way we want.

For this, we have to convert Left from left and vice-versa.

Class 28: Adding Todos UI

• To add extension methods, we must have to add import path of the extension.

• context.formTodos.plusElement may not be available because of missing import statement ,

import 'package:kt_dart/kt.dart';