| name | flutter-riverpod-state-management |
| description | Reactive state management using Riverpod 2.0 with code generation. Use when managing state with Riverpod providers or using riverpod_generator in Flutter. (triggers: **_provider.dart, **_notifier.dart, riverpod, ProviderScope, ConsumerWidget, Notifier, AsyncValue, ref.watch, @riverpod) |
Riverpod State Management
Priority: P0 (CRITICAL)
Type-safe, compile-time safe reactive state management using riverpod and riverpod_generator.
Structure
lib/
├── providers/ # Global providers and services
└── features/user/
├── providers/ # Feature-specific providers
└── models/ # @freezed domain models
Implementation Guidelines
- Generator First: Use @riverpod annotations and
riverpod_generator. Avoid manual Provider definitions.
- Immutability: Maintain immutable states. Use
Freezed for all state models.
- Provider Methods:
ref.watch(): Use inside build() to rebuild on changes. (e.g., ref.watch(productsProvider))
- Side-Effects: Use ref.listen() inside
build() for navigation/dialogs (e.g., ref.listen(cartProvider, (prev, next) { ... }) in ConsumerWidget). Never perform side-effects inside provider initialization.
ref.read(): Use ONLY in callbacks (onPressed).
- Asynchronous Data: Use AsyncNotifier for complex async logic. The
build() method calls the repository (e.g., repository.getProducts()). Access data via .when(data: , loading: , error: ) or AsyncValue pattern-matching.
- Architecture: Enforce 3-layer separation (Data, Domain, Presentation).
- Testing: Override providers in widget tests using ProviderScope(overrides: [provider.overrideWithValue(Mock())]) in
pumpWidget.
- Linting: Enable riverpod_lint and
custom_lint for dependency cycle detection and to catch missing overrides.
Anti-Patterns
- Building Inside Providers: Don't perform side-effects inside provider initialization.
- Context Access: Never pass
BuildContext into a Notifier/Provider.
- Dynamic Providers: Avoid local provider instantiation; keep them global.
Related Topics
layer-based-clean-architecture | dependency-injection | testing