Is it possible to push forward some field via graph.

[Sabrak]

For example:

I have ProfileViewModel

@AssistedInject
class ProfileViewModel(
    @Assisted private val userId: Long,
    private val analytics: Lazy<ProfileAnalytics>,
) : ViewModel() {

    init {
        analytics.value.sendAppear()
    }

    @AssistedFactory
    @ManualViewModelAssistedFactoryKey(
        value = Factory::class,
    )
    @ContributesIntoMap(
        scope = AppScope::class,
    )
    interface Factory : ManualViewModelAssistedFactory {

        fun create(@Assisted userId: Long): ProfileViewModel
    }
}

Also I have ProfileAnalytics class to send events into analytics. For this class I want to pass userId via constructor with others injects classes.

class ProfileAnalytics(
    private val userId: Long, <--- This field must be provided from ProfileViewModel
    private val analytics: Lazy<Analytics>, <--- other injected class
) {
    fun sendAppear() {
        analytics.value.sendEvent(
            name = "profile_appear",
            properties = mapOf(
                "user_id" to userId,
            ),
        )
    }
}

Is it possible to do with metro?

[ZacSweers]

If you want it to participate in your DI graph you need to put that binding on your DI graph rather than have it be an assisted parameter. A common way people handle this scenario is they make a graph extension specific to that scope (for example a ProfileGraph) that takes that ID in as a @Provides input in its factory.

@DependencyGraph
interface AppGraph {
  // ...

  val profileGraphFactory: ProfileGraph.Factory
}

@GraphExtension
interface ProfileGraph {
  @GraphExtension.Factory
  interface Factory {
    fun create(@Provides userId: String): ProfileGraph
  }
}

Then everything in the scope of the ProfileGraph would have access to that userId binding in injection.

[Sabrak]

Big thanks, you make Android dev world better!