Trying to hoist:

val radioOptions = listOf("Calls", "Missed", "Friends")
val (selectedOption, onOptionSelected) = remember { mutableStateOf(radioOptions[0]) }

Which is from the Compose RadioButton example. Am familiar with hoisting when there is one parameter, but in this case there is the extra parameter onOptionSelected which is throwing me off. Currently I have the child composable accepting the two parameters like:

@Composable
fun QuestionRadioButtons(
    selectedOption: String,
    onOptionSelected: (String) -> (Unit)
) { ... }

What’s the question?

What is onOptionSelected and how is it saved by mutableStateOf ?

Your UI composable gets

x

as the current state to “display” in the UI, and an

onXSomething

as the lambda to call upwards when the user interacts with that data display, and that interaction should lead to a state change

Where or how is the onOptionSelected lamba defined?

In this particular simplified case, the

onOptionSelected

is a lambda generated for you with no validation, custom acceptance or rejection, persistence or any other part of it you would have in the real app.