GooglePayLauncher

class PaymentActivity : ComponentActivity(), ReadyCallback, ResultCallback {
    lateinit var button: GooglePayButton
    lateinit var launcher: IGooglePayLauncher

    val gatewayJson = JSONObject()
        .put("gateway", "freedompay")
        .put("gatewayMerchantId", "MyMerchantId")
        .toString()

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.my_payment_view)

        button = findViewById<GooglePayButton>(R.id.my_google_pay_button)
        button.isEnabled = false
        button.setOnClickListener {
            if (!launcher.isReady) {
                return@setOnClickListener
            }

            launcher.present(100)
        }

        launcher = GooglePayLauncher(
            activity = this,
            readyCallback = this,
            resultCallback = this,
            config = Configuration(
                environment = SdkEnvironment.Test,
                gatewayParametersJson = gatewayJson,
                companyName = "Test Company"
            )
        )
    }

    // Update the button state when Google Pay readiness changes
    override fun onReady(isReady: Boolean) {
        button.isEnabled = isReady
    }

    // Handle the result of the Google Pay sheet
    override fun onResult(result: Result) {
        when (result) {
            is Result.Completed -> {
                // Submit the payment data for payment processing (generally to Olo's ordering API)
                // This can be retrieved from result.paymentData
            }
            is Result.Canceled -> {
                // The user canceled the payment
            }
            is Result.Failed -> {
                // An error occurred while attempting to get payment details
                // Details about the error can be retrieved from result.error
            }
        }
    }
}