Quick Start

Use this guide to get the Verifier SDK rendering a verification flow in your Flutter application.

Widget-Based Integration (Recommended)

Use VerificationView for the full verification flow with built-in UI:

import 'package:vecu_verifier_flutter_sdk/vecu_verifier_flutter_sdk.dart';

final sdk = createVerifierSDK(VerifierConfig(
  stage: DeploymentStage.sandbox,
  bearerToken: 'your-vecu-api-token',
));

class VerifyScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return VerificationView(
      sdk: sdk,
      vin: '1HGBH41JXMN109186',
      proximity: const ProximityConfig(thresholdMiles: 5.0),
      onApproved: (result) {
        print('Verified! ${result.requestId}');
        print('Proximity: ${result.proximityCheck?.status}');
        // Navigate to your app's approved screen here
      },
      onDenied: (result) {
        print('DO NOT RELEASE ${result.requestId}');
        // Navigate to your app's denied screen here
      },
      onExpired: (result) {
        print('Session expired');
        // Navigate to your app's expired screen here
      },
      onError: (error) {
        print('${error.code}: ${error.message}');
      },
    );
  }
}

VerificationView handles all states: loading, QR code display with countdown timer, approved (with proximity pass/fail/unchecked), denied, expired, and error.

Callbacks vs SDK Events

When you use VerificationView, the recommended integration point is the callback props:

• onApproved
• onDenied
• onExpired
• onError

These are plain functions your widget passes into the component. Internally, the SDK listens to sdk.on<StatusChangedEvent>(...) and invokes your callbacks when a terminal status arrives.

For full UI control, use VerificationController directly — see the headless example in the SDK repository.

Headless Integration

VerificationController is a ChangeNotifier-based orchestrator for host apps that want to build their own UI while the controller manages API calls, polling, and state transitions:

final controller = VerificationController(
  sdk: sdk,
  vin: '1HGBH41JXMN109186',
  proximity: const ProximityConfig(thresholdMiles: 5.0),
  onApproved: (result) => print('Verified! ${result.requestId}'),
  onDenied: (result) => print('DO NOT RELEASE'),
  onExpired: (_) => print('Expired'),
  onError: (error) => print('Error: ${error.displayCode}'),
);

Build your UI with ListenableBuilder and pattern matching on controller.state:

ListenableBuilder(
  listenable: controller,
  builder: (context, _) {
    return switch (controller.state) {
      LoadingState() => const CircularProgressIndicator(),
      QRState(:final qrContent, :final expiresAt) =>
        MyQRWidget(qrContent, expiresAt),
      ApprovedState(:final result) => MyApprovedWidget(result),
      DeniedState(:final result, :final vin) => MyDeniedWidget(result, vin),
      ExpiredState() => const Text('Session expired'),
      QRExpiredState() => TextButton(
          onPressed: controller.restart,
          child: const Text('QR Expired — Retry'),
        ),
      ErrorState(:final error) => Text('Error: ${error.userMessage}'),
    };
  },
)

Clean up when done:

controller.dispose();
sdk.destroy();

Next Steps

• Integration Guide — Reference architecture for a full verifier app
• API Reference — All widget props, configuration options, and types