Flutter

# pubspec.yaml
dependencies:
  zennopay_flutter: ^0.7.0

<key>NSCameraUsageDescription</key>
<string>Scan a merchant QR code to pay.</string>

ZennopayConfig.sandbox      // https://api.sandbox.zennopay.com — SANDBOX pill (default)
ZennopayConfig.production   // https://api.zennopay.com — real money

// Custom gateway (local dev):
ZennopayConfig.custom('http://localhost:3000')

import 'package:flutter/material.dart';
import 'package:zennopay_flutter/zennopay_flutter.dart';

Future<void> scanAndPay() async {
  // 1. Ask YOUR backend for a checkout session (intent + session token).
  final session = await walletApi.createCheckoutSession();

  // 2. Present the PaymentSheet and await the checkout result.
  final result = await Zennopay.presentSheet(
    intentId: session.intentId,
    sessionJwt: session.sessionToken,
    refreshSession: (intentId) async {
      // Called on session expiry (401): ask your backend to re-mint a token
      // for the SAME intent (POST /v1/payment_intents/:id/session),
      // or return null if you can't.
      final refreshed = await walletApi.refreshSession(intentId);
      return refreshed?.sessionToken;
    },
    config: ZennopayConfig.sandbox, // ZennopayConfig.production for live
  );

  // 3. One terminal case, exhaustively.
  switch (result) {
    case Completed(:final receipt):
      showReceipt(receipt); // refresh wallet state from your backend
    case Pending():
      showPending(); // may still settle — reconcile via webhook/history
    case Canceled():
      break; // user backed out; no money moved
    case Failed(:final error):
      log('payment failed: ${error.code}');
  }
}

sealed class PaymentResult { final String intentId; }

final class Completed extends PaymentResult { final Receipt? receipt; }
final class Canceled  extends PaymentResult {}
final class Failed    extends PaymentResult { final ZennopayError error; }
final class Pending   extends PaymentResult { final Receipt? receipt; }

class Receipt {
  final String? merchantName;
  final int? localAmountMinorUnits;   // satang for THB; VND has no minor unit
  final String? localCurrency;       // native currency code, e.g. "VND"
  final int? amountUsdCents;          // USD debited from the wallet
  final String? transactionId;
  final String? verifiableQrData;    // TH receipt QR; null for VN
  final bool pending;
}

final appearance = ZennopayAppearance(
  mode: ThemeMode.system,
  colors: const ZennopayColors(
    primary: Color(0xFF1B4FD8),
    primaryDark: Color(0xFF6E8EF5),
  ),
  shapes: const ZennopayShapes(card: 10, slide: 12),
  primaryButton: const ZennopayPrimaryButton(
    background: Color(0xFF1B4FD8),
    cornerRadius: 10,
  ),
  logo: const AssetImage('assets/wordmark.png'),
);

final result = await Zennopay.presentSheet(
  intentId: session.intentId,
  sessionJwt: session.sessionToken,
  appearance: appearance,
);