Could we use `LocalSaveableStateRegistry` to store...

# compose-desktop

[TheMrCodes]

Could we use LocalSaveableStateRegistry to store Scrolle state and simular values across the whole application? And if thats the case can anyone describe how it's API is intendet to be used / whats its lifecycle is? Findings in the 🧵

[TheMrCodes]

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.

[TheMrCodes]

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()
        }
    }
}