I am using this BackButtonHandler based on a gist that Adam had shared earlier. I just started trying to use the navigation library in my app but I would still need this handler for taking care of some non-navigation use case. I see this error when I try to use this BackButtonHandler on a screen that was routed through the NavHostController

java.lang.ClassCastException: androidx.navigation.NavBackStackEntry cannot be cast to androidx.appcompat.app.AppCompatActivity
        at com.airbnb.android.showkase.ui.ShowkaseCategoriesScreenKt.ShowkaseCategoriesScreen(ShowkaseCategoriesScreen.kt:85)
        at com.airbnb.android.showkase.ui.ShowkaseBrowserAppKt$ShowkaseBodyContent$1$1.invoke(ShowkaseBrowserApp.kt:160)
        at com.airbnb.android.showkase.ui.ShowkaseBrowserAppKt$ShowkaseBodyContent$1$1.invoke(Unknown Source:13)
        at androidx.compose.runtime.internal.ComposableLambda.invoke(ComposableLambda.kt:153)
        at androidx.compose.runtime.internal.ComposableLambda.invoke(Unknown Source:10)
        at androidx.navigation.compose.NavHostKt$NavHost$5$1.invoke(NavHost.kt:123)
        at androidx.navigation.compose.NavHostKt$NavHost$5$1.invoke(Unknown Source:10)
        at androidx.compose.runtime.internal.ComposableLambda.invoke(ComposableLambda.kt:144)

this is the handler in question

@Composable
internal fun BackButtonHandler(onBackPressed: () -> Unit) {
    Providers(
        AmbientBackPressedDispatcher provides LifecycleOwnerAmbient.current as AppCompatActivity
    ) {
        handler {
            onBackPressed()
        }
    }
}

I started this slack thread for more context and the following discussion - https://kotlinlang.slack.com/archives/CJLTWPH7S/p1604266607160300

tldr; Ian Lake suggested that having something along the lines of a OnBackPressedDispatcherOwnerAmbient would be very useful.