FileEncryptionDemoViewModel.kt

private val encryptedFile by lazy {
    //This is the app's internal storage folder
    val baseDir = getApplication<Application>().filesDir

    //The encrypted file within the app's internal storage folder
    val fileToWrite = File(baseDir, "encrypted-file.txt")

    //Create the encrypted file
    EncryptedFile.Builder(
        fileToWrite,
        getApplication(),
        mainKeyAlias,
        EncryptedFile.FileEncryptionScheme.AES256_GCM_HKDF_4KB
    ).build()
}