name: Android Concurrency description: Standards for Coroutines, Flow, and Threading metadata: labels: [android, concurrency, coroutines, flow] triggers: files: ['**/*.kt'] keywords: ['suspend', 'viewModelScope', 'lifecycleScope', 'Flow']

Android Concurrency Standards

Priority: P0

Implementation Guidelines

Structured Concurrency

• Scopes: Always use viewModelScope (VM) or lifecycleScope (Activity/Fragment).
• Dispatchers: INJECT Dispatchers (DispatcherProvider) for testability. Do not hardcode Dispatchers.IO.

Flow usage

• Cold Streams: Use Flow for data streams.
• Hot Streams: Use StateFlow (State) or SharedFlow (Events).
• Collection: Use collectAsStateWithLifecycle() (Compose) or repeatOnLifecycle (Views).

Anti-Patterns

• GlobalScope: **No GlobalScope**: Use structured scopes.
• Async/Await: **Avoid Async**: Prefer simple suspend functions unless parallel execution is needed.

References

• Dispatcher Pattern