yubioath-flutter/lib/android/qr_scanner/qr_scanner_provider.dart

import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:yubico_authenticator/app/state.dart';
import 'package:yubico_authenticator/cancellation_exception.dart';

import 'qr_scanner_view.dart';

class AndroidQrScanner implements QrScanner {
  final WithContext _withContext;
  AndroidQrScanner(this._withContext);

  @override
  Future<String?> scanQr([String? _]) async {
    var scannedCode = await _withContext(
        (context) async => await Navigator.of(context).push(PageRouteBuilder(
              pageBuilder: (_, __, ___) => const QrScannerView(),
              transitionDuration: const Duration(seconds: 0),
              reverseTransitionDuration: const Duration(seconds: 0),
            )));
    if (scannedCode == null) {
      // user has cancelled the scan
      throw CancellationException();
    }
    if (scannedCode == '') {
      return null;
    }
    return scannedCode;
  }
}

final androidQrScannerProvider = Provider<QrScanner?>(
  (ref) => AndroidQrScanner(ref.watch(withContextProvider)),
);