MainActivity.kt

class MainActivity : AppCompatActivity() {
    lateinit var encryptor: Encryptor
    private val SAMPLE_ALIAS = BuildConfig.MY_ALIAS // save your ALIAS key in local.properties for more security 
 
  init {
        encryptText()
    }
      override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContent {
            MyApplicationTheme {
                // A surface container using the 'background' color from the theme
                Surface(
                    modifier = Modifier.fillMaxSize(),
                    color = MaterialTheme.colorScheme.background
                ) {
                    Greeting(decryptText())
                }
            }
        }
    }
      
    private fun encryptText() {
        try {
            encryptor = EnCryptor()
            val encryptedText = encryptor.encryptText(SAMPLE_ALIAS, BuildConfig.SECRET_KEY) // your secret key form local.properties
            Base64.encodeToString(encryptedText, Base64.DEFAULT)
        } catch (e: Exception) {
            Log.e("TAG", e.message, e)
        }
    }
    private fun decryptText():String {
        val deCryptor = Decryptor()
        try {
            val secretKey = deCryptor.decryptData(SAMPLE_ALIAS, encryptor.encryption, encryptor.iv)
            return  secretKey
        } catch (e: Exception) {
            Log.e("TAG", e.message, e)
            return e.message.toString()
        }
    }
}