I would like to store a Parcelable type via `rememberSaveable` but it doesn t get restored instead it jumps always into the init method of `rememberSaveable` What am I doing wrong ``` val navigator Navigator lt T gt by rememberSaveable stateSaver = Navigator saver backDispatcher = backDispatcher key = State println initial mutableStateOf Navigator initialConfiguration = initialConfiguration backDispatcher = backDispatcher fun lt T Parcelable gt saver backDispatcher OnBackPressedDispatcher = listSaver lt Navigator lt T gt T gt save = navigator gt navigator backStack toList restore = backStack gt Navigator backStack backDispatcher ``` I noticed that `rememberSaveable` is called internally multiple times first time with my provided key and the other times it jumps into the else branch and generates a hash Is this a bug rememberSaveable ``` val finalKey = if key isNullOrEmpty key else currentCompositeKeyHash toString ```

val navigator: Navigator<T> by rememberSaveable(
        stateSaver = Navigator.saver(backDispatcher = backDispatcher),
        key = "State
    ) {
        println("initial")

        mutableStateOf(
            Navigator(
                initialConfiguration = initialConfiguration,
                backDispatcher = backDispatcher
            )
        )
    }

        fun <T : Parcelable> saver(
            backDispatcher: OnBackPressedDispatcher
        ) = listSaver<Navigator<T>, T>(
                save = { navigator -> navigator.backStack.toList() },
                restore = { backStack -> Navigator(backStack, backDispatcher) }
            )

I noticed that

rememberSaveable

is called internally multiple times, first time with my provided key and the other times it jumps into the else branch and generates a hash. Is this a bug? rememberSaveable:

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val finalKey = if (!key.isNullOrEmpty()) {
        key
    } else {
        currentCompositeKeyHash().toString()
    }

Andrey Kulikov

02/19/2021, 9:51 PM

yes, I expect it to work. will you be able to file a bug with a sample project which helps us to reproduce it? thanks

Lilly

02/19/2021, 10:13 PM

@Andrey Kulikov Sure. https://issuetracker.google.com/issues/180701630 Is there a workaround I can use meanwhile?

Andrey Kulikov

02/19/2021, 10:33 PM

so, first of all you don’t really need mutableStateOf as you never update the variable with a new Navigator object:

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val navigator: Navigator<T> = rememberSaveable(
    saver = Navigator.saver(backDispatcher = backDispatcher),
    key = "State"
) {
    Navigator(
        initialConfiguration = initialConfiguration,
        backDispatcher = backDispatcher
    )
}

and looks like it works like this? but I will try to figure out why it didn’t work with state on Monday

Lilly

02/19/2021, 11:35 PM

Ah cool, it works now. I have followed the instructions here: https://developer.android.com/jetpack/androidx/releases/compose-foundation#1.0.0-alpha12 Unfortunately the docs haven't been updated yet. I have also filed a bug for this. See https://kotlinlang.slack.com/archives/CJLTWPH7S/p1613674963285400

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