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Hey! :wave: Is there any way to map values emitted by a `StateFlow` and still have a `StateFlow` and not a `Flow`?
`stateflow.map(::mapper)` returns a `Flow`.

To have another `StateFlow` you would need to store a new state and to have a coroutine that collects the source flow into the new one. You could use <https://kotlin.github.io/kotlinx.coroutines/kotlinx-coroutines-core/kotlinx.coroutines.flow/state-in.html|stateIn> after `map` to do that for you behind the scenes.

:disappointed: Ok, sounds a bit weird coming from Rx, but looks doable. Thanks!

What would you do in Rx? Also, why do you need a `StateFlow` as a result there (why is `Flow` not sufficient)?

I need a `StateFlow` just to have better integration with Jetpack Compose.
In `Rx` a simple `map` on a `BehaviourSubject` would suffice, if I’m not mistaken.

The return type of the `map` method on  `BehaviorSubject` is a plain `Observable` (which is comparable to a plain `Flow`), which gives you the same type of problem that you are asking about.

<http://reactivex.io/RxJava/3.x/javadoc/io/reactivex/rxjava3/subjects/BehaviorSubject.html|http://reactivex.io/RxJava/3.x/javadoc/io/reactivex/rxjava3/subjects/BehaviorSubject.html>

:thinking_face: You’re absolutely right.

<@U021Q17K0HE> FYI, you don't need StateFlow in JetpackCompose

You can collect Flow as state as well
<https://developer.android.com/reference/kotlin/androidx/compose/runtime/package-summary#(kotlinx.coroutines.flow.Flow).collectAsState(kotlin.Any,kotlin.coroutines.CoroutineContext)|https://developer.android.com/reference/kotlin/androidx/compose/runtime/package-summary#(kotlinx.coroutines.flow.Flow).collectAsState(kotlin.Any,kotlin.coroutines.CoroutineContext)>

You can, but you need to supply your own initial value since the collection doesn't begin until initial composition has completed

Most of the time when people ask for this is because they are using StateFlow for hot state instead of snapshots, and snapshots can do this natively <https://github.com/Kotlin/kotlinx.coroutines/issues/2631#issuecomment-859662590|https://github.com/Kotlin/kotlinx.coroutines/issues/2631#issuecomment-859662590>

Yes, that’s exactly my case, Adam. I ended up re-casting my Flow to StateFlow with `stateIn`. Feels a bit weird, but it works.

Although compose `(Mutable) State` is nice, the advantage using `StateFlow` is multiplatform support, especially iOS.