ModalDrawer requires coroutine context to change state hide and show jetpack compose

Question

I need to use a coroutine context to work with modalState.show() or modalState.hide() in my code

@ExperimentalMaterialApi
@Composable
fun ModalBottomSheetLayoutDemo() {
    val modalState = rememberModalBottomSheetState(ModalBottomSheetValue.Hidden)

    Button(modifier = Modifier.padding(16.dp), onClick = { modalState.show() }) {
        Text("Show Bottom Sheet")
    }

    ModalBottomSheetLayout(sheetState = modalState, sheetContent = {
        Text(
            modifier = Modifier.padding(start = 8.dp, top = 8.dp),
            text = "Title",
            fontWeight = FontWeight.Bold,
            style = typography.h5
        )
        Text(
            modifier = Modifier.padding(start = 8.dp, top = 8.dp),
            text = "Content example right here :)",
            style = typography.body1
        )
        Row(modifier = Modifier.align(Alignment.CenterHorizontally).padding(8.dp)) {
            Button(modifier = Modifier.padding(end = 8.dp), onClick = { modalState.hide() }) {
                Text("Cancel")
            }
            Button(onClick = { modalState.hide() }) {
                Text("Ok")
            }
        }
    }, sheetElevation = 8.dp) {}
}

Before it was working and now it requires a coroutine context, how to execute the context within jetpack compose?

Answer 1

Call rememberCoroutineScope() , hold onto it in a variable, and use that to launch() your show() and hide() calls:

@ExperimentalMaterialApi
@Composable
fun ModalBottomSheetLayoutDemo() {
    val modalState = rememberModalBottomSheetState(ModalBottomSheetValue.Hidden)
    val sillyScope = rememberCoroutineScope()

    Button(modifier = Modifier.padding(16.dp), onClick = { sillyScope.launch { modalState.show() } }) {
        Text("Show Bottom Sheet")
    }

    ModalBottomSheetLayout(sheetState = modalState, sheetContent = {
        Text(
            modifier = Modifier.padding(start = 8.dp, top = 8.dp),
            text = "Title",
            fontWeight = FontWeight.Bold,
            style = typography.h5
        )
        Text(
            modifier = Modifier.padding(start = 8.dp, top = 8.dp),
            text = "Content example right here :)",
            style = typography.body1
        )
        Row(modifier = Modifier.align(Alignment.CenterHorizontally).padding(8.dp)) {
            Button(modifier = Modifier.padding(end = 8.dp), onClick = { modalState.hide() }) {
                Text("Cancel")
            }
            Button(onClick = { sillyScope.launch { modalState.hide() } }) {
                Text("Ok")
            }
        }
    }, sheetElevation = 8.dp) {}
}

AFAICT, the suspend call is used because the animation APIs in Compose UI are using coroutines, so we need to apply a suitable CoroutineScope . rememberCoroutineScope() will give you a scope that is good for as long as this branch of your composition is around in some form.