FileEncryptionDemoViewModel.kt

fun writeToEncryptedFile(content: String) {
    //Open the file for writing, and write our contents to it.
    //Note how Kotlin's 'use' function correctly closes the resource after we've finished,
    //regardless of whether or not an exception was thrown.
    encryptedFile.openFileOutput().use {
        it.write(content.toByteArray(StandardCharsets.UTF_8))
        it.flush()
    }
}