Like <@U5F0UDF35>, I'm deeply diving into `nav3` a...

# compose

[Guillaume B]

Like @galex, I'm deeply diving into nav3 and I have a question regarding the scene strategy. Do we have a way for the composables to be aware of the strategy ? Meaning I have a composable that is marked as a detail pane, and I want to modify a bit the ui when that composable is displayed within the scene (vs when it's displayed full screen, not as a detail pane)

[Ian Lake]

Scenes can certainly provide that information, but there is nothing built into the library for that. See the example in https://github.com/android/nav3-recipes/pull/152

[Guillaume B]

yeah saw that, we should definitely have a boolean that let the composable know if within a scene or not (not only for the back button)

I was going that direction but having the info from the scene is def way better

fun PaneScaffoldDirective.isWithinScene(partitionCount: Int) =
    this.maxHorizontalPartitions >= partitionCount

val windowAdaptiveInfo = currentWindowAdaptiveInfo()
val directive = calculatePaneScaffoldDirective(windowAdaptiveInfo)
val withinScene = directive.isWithinScene(2)

[Ian Lake]

Being in a particular Scene isn't any guarantee of anything, which is why the Scene needs to be involved

[Guillaume B]

yeah

[Guillaume B]

So going with creating my own scene, thanks @Ian Lake!

[Stylianos Gakis]

Out of curiosity, is there a way for the Scene to propagate this information down without composition locals?

[Guillaume B]

@Stylianos Gakis Yeah that could be nice to have that info from the scene strategy we have with

val listDetailStrategy = rememberListDetailSceneStrategy<NavKey>()

[Guillaume B]

for now I'm just doing like Don, but instead of mentioning the back button, i'm just telling about the scene

val LocalWithinScene = compositionLocalOf{ false }

[Alex Vanyo]

I wonder if it would be useful to have a LocalScene: CompositionLocal<Scene<T>> where you could pull out information about a Scene (assuming the scene supports it)

[Alex Vanyo]

Out of curiosity, is there a way for the Scene to propagate this information down without composition locals?

It'd be hard, to do it explicitly you'd need to have a way to pass through an extra argument while keeping type-safety through all of the wrapping. A CompositionLocal is probably a simpler cross-cutting mechanism, especially if it is a piece of information that may or may not be available