A Flutter codebase follows the clean architecture and makes it scalable with a modularization approach.
- Flutter v3.x.x
- Clean Architecture
- Presentation use Bloc
- Nguyen Ngoc Huy <huynguyenngoc.dev@gmail.com>
- Clean Architecture
- Dart rule analyze: flutter_lints
- State management: flutter_bloc
- Dependency injection: get_it & injectable_generator
- Network: Dio & Retrofit
- Manage fonts and images: flutter_gen
Framework
- Dart: '>=2.18.0 <3.0.0'
- Flutter: '>=3.0.0'
iOS
- iOS 12+
Android
- Android 7.0+
- minSdkVersion 24
- targetSdkVersion 31
Please turn on your simulator or connect with your physical device before:
- Set up to run:
flutter clean
flutter pub get
flutter pub run build_runner build --delete-conflicting-outputs
- Run with Flavor (dev | stag | prod):
flutter run --flavor development -t lib/main.dev.dart
or
flutter run --flavor staging -t lib/main.staging.dart
or
flutter run --flavor product -t lib/main.product.dart
- If using the another library not build with null-safety. Please run with argument
flutter run --no-sound-null-safety
- Android:
flutter build apk
- iOS:
flutter build ios
Code style:
- Effective Dart If added some assets/fonts/colors
- Use FlutterGen If added some models for api results
- Equatable and json_annotation Auto generate resource(.g.dart/.freezed.dart)
flutter gen-l10n
flutter packages pub run build_runner build --delete-conflicting-outputs
- I use
BLOC
pattern andMVVM
+Clean Architechture
FLUTTER BLOC
-> https://pub.dev/packages/flutter_bloc (PRESENT UI Layer > Business Logic (BLOC or Change notifier) -> REPOSITORY -> DATABASE or SERVICE -> ENTITIES)- Feel free to use
ChangeNotifier
in any simple usecase. - Please push share data model class in
entities
package - App features are located in
modules
package. One feature per sub-module package (please see thetemplate
)
- I use get_it package for Dependency Injection -> https://pub.dev/packages/get_it
- With help of injectable to generate the DI code https://pub.dev/packages/injectable or https://blog.usejournal.com/flutter-di-a-true-love-story-1e5a5ae2ba2d
- I use dio_builder.dart as a
dio
client generator usingsource_gen
and inspired by Chopper and Retrofit.- About
Retrofit
: https://pub.dev/packages/retrofit and https://mings.in/retrofit.dart/ - About
dio
: https://pub.dev/packages/dio - Too lazy to repeat write network layer ? You could try to do it for us
retrofit-generator
https://pub.dev/packages/retrofit_generator - To use
source_gen
, please read here: https://medium.com/flutter-community/part-2-code-generation-in-dart-annotations-source-gen-and-build-runner-bbceee28697b and https://github.com/dart-lang/build/blob/master/docs/writing_a_builder.md#configuring-outputs
- About
This is a diagram that I drew to design and describe this codebase. (to view PDF version )
lib
├── gen
│ ├── l10n
│ │ ├── res_en.dart
│ │ ├── res_vi.dart
│ │ └── res.dart
│ ├── assets.gen.dart
│ ├── colors.gen.dart
│ └── fonts.gen.dart
├── res
│ ├── res_en.arb
│ └── res_vi.arb
├── src
│ ├── core
│ │ ├── base
│ │ │ ├── base_exception_mapper.dart
│ │ │ ├── data_model.dart
│ │ │ ├── entity_item.dart
│ │ │ └── model_item_mapper.dart
│ │ ├── config
│ │ │ ├── app_config.dart
│ │ │ ├── constants.dart
│ │ │ ├── environment.dart
│ │ │ └── themes.dart
│ │ ├── di
│ │ │ ├── dependency_injection.config.dart
│ │ │ ├── dependency_injection.dart
│ │ │ └── locator.dart
│ │ ├── error_handles
│ │ │ ├── alert_exception.dart
│ │ │ ├── app_error.dart
│ │ │ ├── base_exception.dart
│ │ │ ├── inline_exception.dart
│ │ │ ├── on_page_exception.dart
│ │ │ ├── redirect_exception.dart
│ │ │ ├── snack_bar_exception.dart
│ │ │ └── toast_exception.dart
│ │ ├── mapper
│ │ │ ├── exception_mapper.dart
│ │ │ ├── mapper.dart
│ │ │ └── resource_mapper.dart
│ │ ├── models
│ │ │ ├── dialog.dart
│ │ │ ├── error_data_model.dart
│ │ │ ├── error_data_model.g.dart
│ │ │ ├── models.dart
│ │ │ └── tag.dart
│ │ ├── providers
│ │ │ ├── local
│ │ │ │ ├── pref
│ │ │ │ │ ├── app_pref.dart
│ │ │ │ │ └── pref_helper.dart
│ │ │ │ └── app_storage.dart
│ │ │ ├── remote
│ │ │ │ ├── builder
│ │ │ │ │ └── dio_builder.dart
│ │ │ │ ├── interceptor
│ │ │ │ │ └── header_interceptor.dart
│ │ │ │ └── response
│ │ │ │ ├── errors_response.dart
│ │ │ │ └── errors_response.g.dart
│ │ │ └── providers_module.dart
│ │ ├── services
│ │ │ ├── request_permission.dart
│ │ │ └── socket.dart
│ │ ├── types
│ │ │ ├── action.dart
│ │ │ ├── direction_type.dart
│ │ │ ├── exception_type.dart
│ │ │ ├── redirect_type.dart
│ │ │ └── tag_type.dart
│ │ ├── utils
│ │ │ ├── extensions
│ │ │ │ ├── async_snapshot.dart
│ │ │ │ ├── build_context.dart
│ │ │ │ └── context.dart
│ │ │ ├── app_lifecycle.dart
│ │ │ ├── app_size.dart
│ │ │ ├── bloc_observer.dart
│ │ │ └── utils.dart
│ │ ├── core.dart
│ │ ├── endpoints.dart
│ │ └── usecase.dart
│ ├── modules
│ │ ├── app
│ │ │ ├── bloc
│ │ │ │ ├── language_bloc.dart
│ │ │ │ ├── language_event.dart
│ │ │ │ └── language_state.dart
│ │ │ ├── app.dart
│ │ │ └── routes.dart
│ │ ├── authentication
│ │ │ ├── data
│ │ │ │ └── data.dart
│ │ │ ├── domain
│ │ │ │ └── domain.dart
│ │ │ └── presentation
│ │ │ ├── bloc
│ │ │ │ ├── auth_bloc
│ │ │ │ │ ├── auth_bloc.dart
│ │ │ │ │ ├── auth_event.dart
│ │ │ │ │ └── auth_state.dart
│ │ │ │ └── profile_bloc
│ │ │ │ ├── profile_bloc.dart
│ │ │ │ ├── profile_event.dart
│ │ │ │ └── profile_state.dart
│ │ │ ├── forgot_password
│ │ │ │ └── forgot_password_screen.dart
│ │ │ ├── login
│ │ │ │ └── login_screen.dart
│ │ │ ├── profile
│ │ │ │ └── profile_screen.dart
│ │ │ └── register
│ │ │ └── register_screen.dart
│ │ ├── common_widgets
│ │ │ ├── app_indicator.dart
│ │ │ ├── avatar_circle_edit.dart
│ │ │ ├── avatar_circle.dart
│ │ │ ├── loading_popup.dart
│ │ │ ├── popup_modal_custom_content.dart
│ │ │ ├── popup_notification.dart
│ │ │ └── popup.dart
│ │ ├── home
│ │ │ ├── data
│ │ │ │ ├── mappers
│ │ │ │ │ └── fiml_mapper.dart
│ │ │ │ ├── models
│ │ │ │ │ ├── film_model.dart
│ │ │ │ │ ├── film_model.g.dart
│ │ │ │ │ └── models.dart
│ │ │ │ ├── remote_source
│ │ │ │ │ ├── api
│ │ │ │ │ │ ├── film_api.dart
│ │ │ │ │ │ └── film_api.g.dart
│ │ │ │ │ └── response
│ │ │ │ │ ├── film_response.dart
│ │ │ │ │ └── film_response.g.dart
│ │ │ │ └── repository_implementations
│ │ │ │ └── film_repository_impl.dart
│ │ │ ├── domain
│ │ │ │ ├── entities
│ │ │ │ │ └── film_entity.dart
│ │ │ │ ├── repositories
│ │ │ │ │ └── film_repository.dart
│ │ │ │ └── usecases
│ │ │ │ └── film_usecases.dart
│ │ │ └── presentation
│ │ │ ├── bloc
│ │ │ │ └── film_bloc
│ │ │ │ ├── film_bloc.dart
│ │ │ │ ├── film_event.dart
│ │ │ │ └── film_state.dart
│ │ │ ├── detail_film_screen
│ │ │ │ └── detail_film_screen.dart
│ │ │ └── home_screen
│ │ │ └── home_screen.dart
│ │ └── splash
│ │ └── splash.dart
│ └── main.dart
├── main.dev.dart
├── main.product.dart
└── main.staging.dart
It is architecture based on MVVM, CleanArchitecture and the blog by Reso Coder's Flutter Clean Architecture . The main focus of the architecture is separation of concerns and scalability. I will apply this diagram to my mudules in my project.
Every "feature" of the app, like sign in with email and password, will be divided into 3 layers - presentation
, domain
and data
.
The Dependency Rule
Source code dependencies only point inwards
. This means inward modules are neither aware of nor dependent on outer modules. However, outer modules are both aware of and dependent on inner modules. The more you move inward, the more abstraction is present. The outer you move the more concrete implementations are present.
IMPORTANT : Domain represents the inner-most layer. Therefore, it the most abstract layer in the architecture.
Layers
-
Domain It will contain only the core business logic (use cases) and business objects (entities). It should be totally independent of every other layer.
UseCase
: Classes which encapsulate all the business logic of a particular use case of the app (e.g. FetchProfile or UpdateProfile).Entities
: Business objects of the applicationRepositories
: Abstract classes that define the expected functionality of outer layers (data
layer).
I create an abstract Repository class defining a contract of what the Repository must do - this goes into the domain layer. I then depend on the Repository "contract" defined in
domain
, knowing that the actual implementation of the Repository in thedata
layer will fullfill this contract.NOTE: Dependency inversion principle is the last of the SOLID principles. It basically states that the boundaries between layers should be handled with interfaces (abstract classes in Dart).
-
Data: Consists of a Repository implementation (the contract comes from the
domain
layer) and data sources - one is usually for getting remote (API) data and the other for caching that data.Repositories
: Every Repository should implement Repository from thedomain
layer.Datasources
:- remote : responsible for any API call.
- local : reposible for caching data in local database (e.g SQLite, shared_preferences)
Models
: Extensions ofEntities
with the addition of extra members that might be platform-dependent. For example, in the case of parse json Oject from reponse's server, this can be add some specific functionality (toJson, fromJson) or additional fields database.
NOTE: You may notice that data sources don't return
Entities
but ratherModels
. -
Presentation: Contains the UI and the event handlers of the UI.