collecting-flows-safely

Using collectAsState() keeps flows collecting even when the app is backgrounded, wasting CPU and battery. Migrating to collectAsStateWithLifecycle() ties collection to the UI lifecycle, ensuring upstream work pauses when the app enters the background.

To migrate, replace collectAsState() with collectAsStateWithLifecycle() in your Composables, hoist Flow<T> parameters to the caller to collect at the appropriate boundary, and add .conflate() or .distinctUntilChanged() for high-frequency streams where needed.

Use snapshotFlow to bridge State reads for non-UI reactions. snapshotFlow converts Compose State<T> changes into a Flow, allowing you to react to state changes outside of the composition lifecycle using standard Flow operators.

Apply .conflate() and/or .distinctUntilChanged() when dealing with high-frequency streams before collecting them. These operators reduce redundant emissions and ensure the UI only processes the latest or uniquely changed values, optimizing performance.

Verify background pausing by enforcing minActiveState usage and checking trace tooling and logcat. This confirms that upstream work tied to collectAsStateWithLifecycle actually stops when the lifecycle drops below the minimum active state.

You should avoid using Lifecycle.State.CREATED for flow collection. Enforcing minActiveState with collectAsStateWithLifecycle requires careful state management to ensure collection only happens when the lifecycle is in an appropriate active state.