backstack-10.kt

@Composable
fun Content(backPress: Backpress, cantPopBackStack: () -> Unit) {

    // remainder omitted

    var unhandledCount = +memo { State(0) }
    val nbChildren = 2
    val cantPopBackStackDelegate = {
        // if we tried all of them and failed...
        if (++unhandledCount.value == nbChildren) {
            // ...then comes our local handling
            if (!backStack.pop()) {
                cantPopBackStack()
            }
            // don't forget to reset
            unhandledCount.value = 0
        }
    }

    SomeChild1.Content(
        backPress = backPress,
        cantPopBackStack = cantPopBackStackDelegate
    )

    SomeChild2.Content(
        backPress = backPress,
        cantPopBackStack = cantPopBackStackDelegate
    )

    // and so on ...
}