composables_swap_basic.kt

Box(
    modifier = Modifier
        .fillMaxSize()
) {
    var containerState by remember { mutableStateOf(ContainerState.Fab) }
    HotTakesContent()
    when (containerState) {
        ContainerState.Fab -> Fab(
            modifier = Modifier
                .align(Aligment.BottomEnd)
                .padding(end = 16.dp, bottom = 16.dp),
            onClick = { containerState = ContainerState.Fullscreen }
        )
        
        ContainerState.Fullscreen -> AddContentScreen(
            onBack = { containerState = ContainerState.Fab } 
        )
    }
}