Inttegro Flutter

API reference · Studio guide

Typed Flutter facade for Inttegro's native payment sheet. This is an implementation spike and is not ready to publish or use with live payments. The current collection surface supports mobile money; card, Apple Pay, and Google Pay are not exposed.

// Your backend must create and finalize the Order before this handoff.
final checkout = await merchantBackend.createCheckoutOrder(cart);
final orderId = checkout.orderId;

final lifecycleSubscription = Inttegro.instance.paymentSheetEvents.listen(
  (event) {
    switch (event.type) {
      case PaymentSheetEventType.presented:
        onPaymentFlowStarted();
      case PaymentSheetEventType.paymentAttemptStarted:
        onPaymentAttemptStarted();
      case PaymentSheetEventType.paymentAttemptFailed:
        // Recoverable: the customer can retry without leaving the native sheet.
        onPaymentAttemptFailed(category: event.errorType);
      default:
        break;
    }
  },
);

await Inttegro.instance.initializePaymentSheet(
  PaymentSheetConfiguration(
    orderId: orderId,
    returnUrl: Uri.parse('merchant-app://inttegro-return'),
    telemetry: activeTraceContext, // Optional traceparent and tracestate.
  ),
);

try {
  final result = await Inttegro.instance.presentPaymentSheet();

  switch (result) {
    case PaymentSheetCompleted(:final paymentId):
      onPaymentCompleted(paymentId: paymentId);
      await merchantBackend.verifyOrderPayment(orderId);
    case PaymentSheetCanceled():
      onPaymentCanceled();
    case PaymentSheetFailed(:final code, :final message, :final declineCode):
      onPaymentSheetFailed(
        code: code,
        message: message,
        declineCode: declineCode,
      );
  }
} finally {
  await lifecycleSubscription.cancel();
}

Finalizing an Order seals its amount and activates checkout; it does not mean the payment has completed. Treat PaymentSheetCompleted as immediate client UI state. Verify the owner-scoped Order from your backend before fulfillment.

The method channel maps directly to the shared native iOS and Android payment artifacts. Those native implementations own presentation, accessibility, authentication, payment collection, and lifecycle state; Dart only validates the public input and decodes the result.

paymentSheetEvents provides typed application-facing lifecycle events. A failed attempt is recoverable and does not resolve the presentation; the terminal PaymentSheetResult drives completion, cancellation, and sheet-failure behavior.

Use paymentSheetTelemetryEvents separately for ordered Checkout network diagnostics. Inttegro does not install or own an exporter: the host decides whether to translate them into spans, logs, or other signals. Events contain bounded status and correlation metadata, never Order or Payment IDs, customer or payer data, payment-method details, request or response bodies, redirect URLs, or raw error messages. flowId and requestId should not be used as metric labels. Subscribe before presenting the sheet so the first event is not missed.

The package registers an Android and iOS plugin for each Flutter engine. The plugins keep presentation state isolated per engine and delegate to the same native Inttegro artifacts used by the React Native SDK. CocoaPods links the iOS artifact through inttegro_flutter.podspec, while Gradle resolves com.inttegro:inttegro-android:0.1.0.

Requirements

• Flutter 3.44 or later and Dart 3.12 or later
• iOS 16 or later
• Android API 26 or later

Add the package, fetch dependencies, and rebuild the application so Flutter can register the native plugin. Hot reload alone cannot add a newly installed native plugin to a running application.