Hey Arkadii! :wave: Would this be the correct way to get the previous child in the backstack to deci...

# decompose

[Nacho Ruiz Martin]

Hey Arkadii! 👋
Would this be the correct way to get the previous child in the backstack to decide what action to take depending on where you come from?

val originIndex = childStack.value.backStack.lastIndex - 1
when (val child = childStack.value.backStack[originIndex].instance) {
    is MainBloc.SomeChild -> someAction()
    ... ->
    else -> navigation.pop() //Shouldn't be the case
}

Also, would it make sense to have extensions for this in the library API?

[Arkadii Ivanov]

Given the childStack is defined as Value<ChilfStack>, I believe you can do the following:

val active = childStack.active.instance
val previous = childStack.backStack.lastOrNull()

Keep in mind that the backStack property doesn't include the active component. There is the items property that includes all components.

[Arkadii Ivanov]

The back stack can be empty, while there is always an active component.

[Nacho Ruiz Martin]

Keep in mind that the backStack property doesn’t include the active component.

Oh, didn’t know that one! Thanks for it 🙂

[Arkadii Ivanov]

Good point, I'll expand docs for ChildStack. Filed https://github.com/arkivanov/Decompose/issues/518

[Nacho Ruiz Martin]

😅. Not the most descriptive commit, but surely sincere.