App Architecture & Repository Pattern

Build App Architecture & Repository Pattern as a flow that separates UI, domain logic, data sources, and failure states. Handle loading, empty, success, error, retry, cancellation, and route restoration explicitly.

Build a Complete Mental Model

Build App Architecture & Repository Pattern as a flow that separates UI, domain logic, data sources, and failure states. Handle loading, empty, success, error, retry, cancellation, and route restoration explicitly.

Apply It in Production Flutter

Run and test an original App Architecture & Repository Pattern example with small and large screens, text scaling, empty/loading/error states, rapid interaction, navigation restoration, and disposal cases. Use flutter analyze, widget tests, and profile mode where relevant.

After This Lesson

• Explain constraints, state ownership, and lifecycle
• Write an example that passes flutter analyze
• Test a widget interaction or failure state

abstract interface class TaskRepository {
  Future<List<String>> fetchTasks();
}

final class MemoryTaskRepository implements TaskRepository {
  @override
  Future<List<String>> fetchTasks() async => ['Learn', 'Build', 'Test'];
}

final class TaskController {
  TaskController(this.repository);
  final TaskRepository repository;
  Future<List<String>> load() => repository.fetchTasks();
}

UI-independent data access that can be replaced in tests

Flutter documentation — Flutter