Another question about the new `SavedStateHandle.saveable` API, is there an equivalent to ```val arg...

# compose

[nitrog42]

Another question about the new SavedStateHandle.saveable API, is there an equivalent to

val argArticleId = savedStateHandle.getStateFlow(ArticleArgKey, -1)

that return a State ?
I tried with .saveable(ArticleArgKey) but it seems the return value is a Bundle instead of a Long... (in my case)

[Ian Lake]

If you have a StateFlow, you call collectAsState() to make it into State. That is true for SavedStateHandle and for any other StateFlow.

[nitrog42]

yes for collectAsState(), but I meant more as having directly a State in the ViewModel

[nitrog42]

I’m starting to use more and more MutableState in my ViewModels instead of StateFlow and... I kinda like it 😄

[Ian Lake]

You have the SavedStateHandle itself in the ViewModel, you don't need a StateFlow or State for working with that

[Ian Lake]

Maybe you could explain what you're trying to do?

[nitrog42]

well nothing really interesting 😄
basically, here is a sample viewmodel :

@HiltViewModel
class MyViewModel @Inject constructor(
    private val savedStateHandle: SavedStateHandle
) : ViewModel() {
    val someItemId: StateFlow<Long> = savedStateHandle.getStateFlow(ItemIdArg, -1L)

    /**
     * Some State
     */
    var someState: SomeState by mutableStateOf(SomeState())
        private set

    /**
     * Some state for the UI
     */
    var someSavedState: SomeState by savedStateHandle.saveable(key = "SomeState", stateSaver = SomeState.Saver, init = {
        mutableStateOf(
            SomeState()
        )
    })
        private set
}

We can expose the state either through mutableStateOf directly, or use the new saveable api to get it saved in the `SavedStateHandle`/`rememberSaveable`

now my Screen receive an arg through Navigation, let’s say a `detailId`;
You can get this arg using simply handle.getStateFlow(ArgKey)
and I was wondering if there was a similar helper that returns a Compose State<> / MutableState<>
(so we can use it directly from a Composable, or use it in the ViewModel, the same as the SomeState I have)

[nitrog42]

trying to TLDR : we can listen/get NavArgs through SavedStateHandle with `LiveData`/`StateFlow`, and I was wondering if there was a similar api for `State`/`MutableState`

[Ian Lake]

Args you get from Navigation should be considered a static values (they are part of the identity of what screen you're on), so using StateFlow or anything is already unnecessary - just a single get is enough

[nitrog42]

hmmm that’s right !