A modern programming language that makes developers happier.

kotlinlang

```@NoLiveLiterals
@Composable
fun DonationForm() {
  var selected by remember { mutableStateOf(values[1]) }
  val coroutineScope = rememberCoroutineScope()
  
  val clientSecret = coroutineScope.async { startDonation(selected.toLong().times(100)) }```
Hey guys!
How to make `clientSecret` render again everytime `selected` is changed?
`selected` gets it's state correctly, but `clientSecret` is being calculated only once (and not recalculating on recomposition)

Doing
```val clientSecret = selected.run { coroutinescope.... } ```
works

I'm wondering if there's a way to do this differently

Hmm, try this?
```var clientSecret by remember { mutableStateOf(1L) }
coroutineScope.launch {
  clientSecret = startDonation(selected.toLong().times(100))
}```

I have no idea why selected.run works :face_palm:

I'd assume selected.run compiles to the same thing as your first case (run being an inline fun)

Maybe you're doing something different in the ommitted part (`...`)?

I'll try again. My assumption was tthat with `selected.run` I'd trigger recomposition because `selected` would change inside a @Compose function

Not inside the coroutine async block, if that makes any sense

My thought was that triggering DonationForm recomposition would trigger the `selected` line

The run was used only to get the value in an expression, which was what I thought could trigger the recomposition to work

Then I think my proposed solution is less hacky

You could also try using SideEffects API for this as well.

That way you can control when the effects are executed better (as opposed to launching coroutine each composition)

what about `derivedState`? Or `remember(selected)`?

I don't know what either of those are <@U01JRLZH77T> :joy:

`derivedState` updates the calculation if a state used inside the calculation block was changed.
alternative using selected as a key for `remember` will result into the same behavior: if the key of remember was changed, the calculation will be executed again. Difference between remember and derivedState is optimization, in `derivedState` the compiler knows, the reason for recalculation was this state change, so it the recalculation can be scheduled right after the change of the state (change, recalculation, recomposing), and not after changing, recomposing and recalculation and recomposing again.

In general you don't want to perform side effects like launching async work directly from compositions. Use effect handlers. 