In the last hour I digged deeper into

LocalSaveableStateRegistry

and found out that its already implemeted into an class named

SaveableStateHolder

that implements the exact behaivir I wanted. It saves the

LocalSaveableStateRegistry

by a key and provides it in a local scope inside the content of its

SaveableStateProvider

method.

Here's a small example using this method to create an custom screen navigator that implements an`SaveableStateHolder` to use a SaveableStateRegistry per screen:

Box(Modifier.fillMaxSize()) {
    var screen by rememberMutableStateOf("Home")
    val registry = rememberSaveableStateHolder()
    
    val screens = mapOf<String, @Composable () -> Unit>(
        "Home" to {
            Button(onClick = { screen = "Detail" }) {
                Text("To Detail")
            }
            Text("Home")
            var cnt by rememberSaveable { mutableStateOf(0) }
            Button(onClick = { cnt++ }) {
                Text("Count: $cnt")
            }
        },
        "Detail" to {
            Button(onClick = { screen = "Home" }) {
                Text("To Home")
            }
            Text("Detail")
            var cnt by rememberSaveable { mutableStateOf(0) }
            Button(onClick = { cnt++ }) {
                Text("Count: $cnt")
            }
        }
    )
    
    Row {
        registry.SaveableStateProvider(screen) {
            screens[screen]?.invoke()
        }
    }
}