How does Jetpack Compose update your UI when state changes?
The key component is the Recomposer.
It observes, schedules, and applies changes to your Composables.
Let’s learn how it works 🧵
The key component is the Recomposer.
It observes, schedules, and applies changes to your Composables.
Let’s learn how it works 🧵
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It watches for state changes, identifies affected Composables, and re-executes them so the UI stays in sync with data.
This function:
✅ Waits for the next frame
✅ Gathers invalidated compositions
✅ Performs recomposition
✅ Applies the resulting changes
- Inactive (not observing)
- Idle (waiting for work)
- PendingWork (work is queued)
- ShuttingDown (being cancelled)
These help manage its operation and shutdown process.
When state changes, only the affected Composables are re run.
This leads to efficient and targeted updates.
This allows it to track reads and writes to snapshot state and determine exactly what needs to be recomposed.
✅ Structured concurrency
✅ Support for cancellation
✅ The ability to suspend and resume safely