MainActivity.kt

class MainActivity : ComponentActivity() {

    private lateinit var requestMultiplePermission: ActivityResultLauncher<Array<String>>

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        requestMultiplePermission = registerForActivityResult(
            ActivityResultContracts.RequestMultiplePermissions()
        ){
            var isGranted = false
            it.forEach { s, b ->
                isGranted = b
            }

            if (!isGranted){
                Toast.makeText(this, "Permission Not Granted", Toast.LENGTH_SHORT).show()
            }
        }
        
        setContent {
            DownloadFileWorkManagerDemoTheme {
                Surface(
                    modifier = Modifier.fillMaxSize(),
                    color = MaterialTheme.colors.background
                ) {
                    requestMultiplePermission.launch(
                        arrayOf(
                            Manifest.permission.READ_EXTERNAL_STORAGE,
                            Manifest.permission.WRITE_EXTERNAL_STORAGE
                        )
                    )

                    Home()
                }
            }
        }
}