Hi, if invalidation occurs, it is recorded in `inv...

# compose

[Ji Sungbin]

Hi, if invalidation occurs, it is recorded in invalidateStack, and if this stack is not empty, it is popped from this stack and returned from endRestartGroup(). Recomposition is performed through the returned RecomposeScope. Right? However, if there is no invalidation during the composition process, null is returned, and if invalidation is requested later, how does endRestartGroup() detect this and recompose again?

If look at the implementation of endRestartGroup(), there is no code to track invalidations. Only request pop once.

val scope = if (invalidateStack.isNotEmpty()) invalidateStack.pop() else null // RecomposeScopeImpl?

EDIT: I found some clues. Suspend until invalidation is added through awaitWorkAvailable() in Recomposer.runRecomposeAndApplyChanges(). If there is a waiting task(hasSchedulingWork), it immediately resumes Continuation and proceeds to recompose. Otherwise, it maintains the suspend state. The maintained suspend(CancellableCoroutine) is resumed when the operation is completed through the effectJob, but as I traced the places where the effectJob is used, there are only rememberCoroutineScope() and LaunchedEffect. Where will this suspend resume? I think it’s time to record invalidation, but it wasn’t. They are recorded regardless of Job.

[Alexandre Elias [G]]

well, it seems like your puzzlement might be because you're looking primarily at the invalidation code in Composer.kt, but it's only responsible for a portion of the invalidation logic. invalidate calls flow up to the Recomposer.kt , which is the parent of the root CompositionContext.

[Alexandre Elias [G]]

with respect to your questions about when we wake up to resume activity, note also that the code assumes an integration with the operating system invalidation model. On Android, Compose ties in to the Choreographer animate/measure/draw callbacks instead of handling scheduling with pure standard library Kotlin

[Alexandre Elias [G]]

I'm not sure precisely what you're asking here but anyway, it sounds like expanding your research to Recomposer and Choreographer might clarify things for you

[Ji Sungbin]

Thank you so much 🥰
I will investigate again with your comments.