API Reference

MrtCardReader

`static Future<bool> isAvailable()`

Checks whether NFC is available and enabled on the current device.

`static Future<void> startSession(...)`

Starts an NFC session and streams card reading output through callbacks.

await MrtCardReader.startSession(
  onStatus: (status) {},
  onBalance: (balance) {},
  onTransactions: (transactions) {},
  onError: (exception) {},
  timeout: const Duration(seconds: 30),
);

Key callback inputs

onStatus: scan progress and status updates.
onBalance: current card balance (paisa).
onTransactions: parsed transaction list.
onError: typed exception callback (recommended).
timeout: optional session timeout.

Instance API (advanced control)

Use MrtCardReaderInstance if you need explicit session lifecycle management.

final reader = MrtCardReaderInstance(
  logger: ConsoleLogger(),
  timeout: const Duration(seconds: 60),
);

await reader.startSession(
  onStatus: (status) => print(status),
  onBalance: (balance) => print(balance),
  onTransactions: (transactions) => print(transactions),
  onError: (exception) => print(exception),
);

if (reader.isSessionActive) {
  print('Reading in progress...');
}

await reader.cancelSession();

MrtTransaction model

Common fields exposed in each transaction item:

fixedHeader
timestamp
transactionType
fromStation
toStation
balance
cost
trailing
isTopup

Utility methods include copyWith, toMap, fromMap, and toString.

Typed exceptions

The package includes explicit exceptions for predictable error handling:

MrtException
NfcNotAvailableException
InvalidCardException
DataCorruptionException
NfcTimeoutException
SessionAlreadyActiveException