A `LifecycleOwner` that can switch between mirroring of its parent's state and an overridden state

mirroringLifecycleOwner.kt

import androidx.compose.runtime.Composable
import androidx.compose.runtime.Immutable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.remember
import androidx.compose.ui.platform.LocalLifecycleOwner
import androidx.lifecycle.Lifecycle
import androidx.lifecycle.LifecycleOwner
import androidx.lifecycle.LifecycleRegistry
import androidx.lifecycle.compose.currentStateAsState

@Composable
fun mirroringLifecycleOwner(mirrorMode: LifecycleMirrorMode): LifecycleOwner {
  val parentLifecycle = LocalLifecycleOwner.current.lifecycle
  val parentLifecycleState by parentLifecycle.currentStateAsState()

  val childLifecycleOwner = remember(parentLifecycle) {
    object : LifecycleOwner {
      val lifecycleRegistry = LifecycleRegistry(provider = this).apply {
        currentState = mirrorMode.choose(parentLifecycleState)
      }
      override val lifecycle: Lifecycle get() = lifecycleRegistry
    }
  }
  return childLifecycleOwner.apply {
    lifecycleRegistry.currentState = mirrorMode.choose(parentLifecycleState)
  }
}

@Immutable
sealed interface LifecycleMirrorMode {
  data object MirrorParent : LifecycleMirrorMode
  data class Override(val withState: Lifecycle.State) : LifecycleMirrorMode

  fun choose(parentState: Lifecycle.State): Lifecycle.State {
    return when (this) {
      is MirrorParent -> parentState
      is Override -> if (parentState.isAtLeast(withState)) withState else parentState
    }
  }
}

Usage:

val pagerState = rememberPagerState(...)

HorizontalPager(pagerState) { pageNum ->
  val pageLifecycleOwner = mirroringLifecycleOwner(
    mirrorMode = when (pagerState.settledPage) {
      pageNum -> LifecycleMirrorMode.MirrorParent
      else -> LifecycleMirrorMode.Override(Lifecycle.State.CREATED)
    }
  )
  CompositionLocalProvider(LocalLifecycleOwner provides pageLifecycleOwner) {
    // Your pages here.
  }
}