我目前正在为我的应用开发主屏幕，但我遇到了一个问题。val context = LocalContext.current行导致了一个错误，该错误指出，“@Composable invocations can only happen from the context of a @Composable function”。您能否提供有关如何解决此问题的指导？为了给予更好的理解，以下是完整的函数：

@Composable
fun HomeScreen(navController: NavController) {
    // Use a Box to allow for layering of composables on top of each other
    // Used to keep the content at the bottom center of the screen.
    Box(
        modifier = Modifier
            .fillMaxSize()
            .padding(16.dp), // Apply padding around the box
        contentAlignment = Alignment.BottomCenter // Align content to the bottom center
    ) {
        // Column to stack buttons vertically
        Column(
            // Center column contents horizontally
            horizontalAlignment = Alignment.CenterHorizontally,
            // Space between the column contents
            verticalArrangement = Arrangement.spacedBy(8.dp)
        ) {
            // Button to NAVIGATE TO THE BENEFITS SCREEN
            Button(
                onClick = { navController.navigate("sleep_benefits") },
                // Apply padding to only the top of the first button to push it upwards
                modifier = Modifier.padding(bottom = 1.dp)
            ) {
                Text(text = "Learn About Sleep Benefits")
            }
            // Button for USER LOGIN
            Button(
                onClick = { /* TODO: Add navigation to login screen here */ }
            ) {
                Text(text = "Login to Track Sleep")
            }
            // New Sign Up Button
            Button(
                onClick = {
                    val context = LocalContext.current
                    context.startActivity(Intent(context, SignInActivity::class.java))
                },
                modifier = Modifier.padding(top = 8.dp)
            ) {
                Text(text = "Sign Up")
            }
        }
    }
}

字符串
我试着看这个：Error: "@Composable invocations can only happen from the context of a @Composable function"