How to Use NFC for Payments and Event Check-ins in FlutterFlow

1# pubspec.yaml additions
2dependencies:
3  nfc_manager: ^3.3.0
4  pay: ^2.0.0
5
6# ios/Runner/Info.plist — add inside <dict>:
7# <key>NFCReaderUsageDescription</key>
8# <string>Scan event badges and product NFC tags</string>
9
10# android/app/src/main/AndroidManifest.xml — add inside <manifest>:
11# <uses-permission android:name="android.permission.NFC" />
12# <uses-feature android:name="android.hardware.nfc" android:required="false" />

1// lib/custom_actions/read_nfc_tag.dart
2import 'package:nfc_manager/nfc_manager.dart';
3
4Future<String?> readNfcTag() async {
5  bool isAvailable = await NfcManager.instance.isAvailable();
6  if (!isAvailable) return null;
7
8  String? result;
9  await NfcManager.instance.startSession(
10    onDiscovered: (NfcTag tag) async {
11      final ndef = Ndef.from(tag);
12      if (ndef == null) {
13        await NfcManager.instance.stopSession(errorMessage: 'Tag not NDEF formatted');
14        return;
15      }
16      final message = ndef.cachedMessage;
17      if (message == null || message.records.isEmpty) {
18        await NfcManager.instance.stopSession(errorMessage: 'No data on tag');
19        return;
20      }
21      final record = message.records.first;
22      // Decode text payload (skip language code bytes)
23      final payload = record.payload;
24      final languageCodeLength = payload[0] & 0x3F;
25      result = String.fromCharCodes(
26          payload.sublist(1 + languageCodeLength));
27      await NfcManager.instance.stopSession();
28    },
29  );
30  return result;
31}

1// lib/custom_actions/write_nfc_tag.dart
2import 'dart:io';
3import 'package:nfc_manager/nfc_manager.dart';
4
5Future<bool> writeNfcTag(String payload) async {
6  if (!Platform.isAndroid) {
7    // iOS does not support third-party NFC writing
8    return false;
9  }
10  bool isAvailable = await NfcManager.instance.isAvailable();
11  if (!isAvailable) return false;
12
13  bool success = false;
14  await NfcManager.instance.startSession(
15    onDiscovered: (NfcTag tag) async {
16      final ndef = Ndef.from(tag);
17      if (ndef == null || !ndef.isWritable) {
18        await NfcManager.instance.stopSession(
19            errorMessage: 'Tag is not writable');
20        return;
21      }
22      try {
23        await ndef.write(NdefMessage([
24          NdefRecord.createText(payload),
25        ]));
26        success = true;
27        await NfcManager.instance.stopSession();
28      } catch (e) {
29        await NfcManager.instance.stopSession(errorMessage: e.toString());
30      }
31    },
32  );
33  return success;
34}

1// lib/custom_actions/show_payment_sheet.dart
2import 'package:pay/pay.dart';
3import 'dart:convert';
4
5Future<String?> showPaymentSheet(String itemName, double amount) async {
6  final paymentItems = [PaymentItem(label: itemName, amount: amount.toStringAsFixed(2))];
7
8  // Apple Pay configuration
9  final applePayConfig = PaymentConfiguration.fromJsonString(jsonEncode({
10    'provider': 'apple_pay',
11    'data': {
12      'merchantIdentifier': 'merchant.com.yourapp',
13      'displayName': 'Your App',
14      'merchantCapabilities': ['3DS', 'debit', 'credit'],
15      'supportedNetworks': ['amex', 'visa', 'masterCard'],
16      'countryCode': 'US',
17      'currencyCode': 'USD',
18    }
19  }));
20
21  try {
22    final result = await Pay.withAssets(['apple_pay.json']).showPaymentSelector(
23      PayProvider.apple_pay,
24      paymentItems,
25    );
26    // result contains the payment token — send to your backend
27    return jsonEncode(result);
28  } catch (e) {
29    return null;
30  }
31}