quickqr_scanner_plugin 1.0.2

Enterprise-grade QR code scanner with Vision framework integration for iOS and ML Kit for Android. High-performance, low-latency scanning with comprehensive error handling.

QuickQR Scanner Plugin

Enterprise-grade QR code and barcode scanner plugin for Flutter with native Vision framework integration for iOS and ML Kit for Android. Designed for production apps requiring high-performance, low-latency scanning with comprehensive error handling.

🌟 Features

• Native Performance: Vision framework (iOS) + ML Kit (Android) for optimal speed
• Real-time Scanning: Live camera scanning with sub-second detection
• Platform Views: Native camera integration with Flutter UI overlay
• Enterprise Error Handling: Comprehensive status reporting and recovery
• Image Processing: Advanced quality analysis and enhancement
• Multiple Formats: QR Code, Code 128, Code 39, EAN-13, EAN-8, UPC-E
• Permission Management: Graceful camera permission handling
• Resource Management: Proper cleanup and memory management
• Minimal Dependencies: Lightweight with essential libraries only

📱 Supported Platforms

Platform	Version	Framework	Performance
iOS	12.0+	Vision + AVFoundation	Hardware acceleration on supported devices
Android	API 21+	ML Kit + Camera2 API	Google ML optimization

🚀 Installation

Add this to your package's pubspec.yaml file:

dependencies:
  quickqr_scanner_plugin: ^1.0.0

Then run:

flutter pub get

iOS Configuration

Add camera permission to ios/Runner/Info.plist:

<key>NSCameraUsageDescription</key>
<string>This app needs camera access to scan QR codes</string>

Android Configuration

Add camera permission to android/app/src/main/AndroidManifest.xml:

<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" android:required="true" />

💡 Quick Start

Basic Usage

import 'package:quickqr_scanner_plugin/quickqr_scanner_plugin.dart';

class QRScannerPage extends StatefulWidget {
  @override
  _QRScannerPageState createState() => _QRScannerPageState();
}

class _QRScannerPageState extends State<QRScannerPage> {
  final _scanner = QuickqrScannerPlugin();
  StreamSubscription<QRScanResult>? _subscription;

  @override
  void initState() {
    super.initState();
    _initializeScanner();
  }

  Future<void> _initializeScanner() async {
    // Check device availability
    final availability = await _scanner.checkAvailability();
    if (!availability['isAvailable']) {
      print('QR scanning not supported on this device');
      return;
    }

    // Check permissions
    final permissions = await _scanner.checkPermissions();
    if (permissions['status'] != 'granted') {
      final requested = await _scanner.requestPermissions();
      if (!requested['granted']) {
        print('Camera permission required');
        return;
      }
    }

    // Initialize scanner
    await _scanner.initialize();
    
    // Listen for scan results
    _subscription = _scanner.onQRDetected.listen((result) {
      print('QR Code detected: ${result.content}');
      print('Format: ${result.format}');
      print('Confidence: ${result.confidence}');
    });

    // Start scanning
    await _scanner.startScanning();
  }

  @override
  void dispose() {
    _subscription?.cancel();
    _scanner.dispose();
    super.dispose();
  }
}

Image-based Scanning

// Scan QR code from image file
Future<void> scanFromImage(String imagePath) async {
  final scanner = QuickqrScannerPlugin();
  final result = await scanner.scanFromImage(imagePath);
  if (result != null) {
    print('QR Code: ${result.content}');
    print('Format: ${result.format}');
  } else {
    print('No QR code found in image');
  }
}

📖 API Reference

QuickqrScannerPlugin

Main plugin class providing QR scanning functionality.

Properties

• static instance - Singleton instance
• onQRDetected - Broadcast Stream for real-time scan results
  • Emits QR/barcode detection events during active scanning
  • Supports multiple listeners with automatic error recovery
  • ⚠️ Remember to cancel subscriptions in dispose() to prevent memory leaks

Methods

Device Information

Future<Map<String, dynamic>> checkAvailability()

Returns device scanning capabilities and supported formats.

Future<Map<String, dynamic>> checkPermissions()

Checks current camera permission status.

Future<Map<String, dynamic>> requestPermissions()

Requests camera permissions from user.

Scanner Control

Future<Map<String, dynamic>> initialize([QRScanConfig? config])

Initializes the scanner with optional configuration.

Future<void> startScanning()

Starts real-time QR code scanning.

Future<void> stopScanning()

Stops the scanning process.

Future<void> dispose()

Releases all resources and cleans up.

Additional Features

Future<Map<String, dynamic>> toggleFlashlight()

Toggles device flashlight (if available).

Future<QRScanResult?> scanFromImage(String imagePath)

Scans QR code from image file.

Data Models

QRScanResult

class QRScanResult {
  final String content;     // QR code content
  final String format;      // Barcode format (qr, code128, etc.)
  final int timestamp;      // Detection timestamp (milliseconds)
  final double confidence;  // Detection confidence (0.0-1.0)
}

📱 Example App

A comprehensive example app is included in the example/ directory demonstrating:

• Device capability detection
• Permission handling
• Real-time scanning with visual feedback
• Image-based scanning
• Error handling and recovery
• Scan result management
• Flashlight control

To run the example:

cd example
flutter run

🛠 Performance Notes

iOS (VisionKit)

• High Performance: Native system integration
• Low Battery Usage: Optimized Apple Vision framework
• System UI: Consistent with iOS design patterns
• Neural Engine: Hardware acceleration on supported devices

Android (ML Kit)

• Google ML: Powered by Google's machine learning
• On-device Processing: No internet connection required
• Broad Compatibility: Works on API level 21+
• Efficient Detection: Optimized for mobile devices

🚨 Troubleshooting

Common Issues

"Camera permission denied"

• Ensure camera permission is added to platform manifests
• Check that user has granted permission in device settings
• Use checkPermissions() and requestPermissions() methods

"Scanner not initialized"

• Call initialize() before starting scanning
• Ensure initialization completes successfully before calling other methods
• Check device compatibility with checkAvailability()

"No camera available"

• Verify device has camera hardware
• Check that camera isn't being used by another app
• Try restarting the app or device

Debug Mode

Enable detailed logging in debug builds:

// Add to main.dart for debugging
void main() {
  if (kDebugMode) {
    print('QuickQR Scanner Plugin Debug Mode Enabled');
  }
  runApp(MyApp());
}

📄 License

This project is licensed under the MIT License - see the LICENSE file for details.

🤝 Contributing

We welcome contributions! Please see CONTRIBUTING.md for details on how to get started.

📞 Support

• Documentation: API Reference
• Examples: More Examples
• Issues: GitHub Issues
• Discussions: GitHub Discussions

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