Flutter Urovo RFID

A Flutter plugin that provides seamless integration with Urovo's Android RFID hardware, enabling Flutter applications to interact with Urovo RFID readers. The plugin wraps Urovo's native Android SDK, exposing a clean and easy-to-use Dart API.

Features

• Power on/off and connect to Urovo RFID readers
• Start and stop continuous inventory scanning
• Perform single inventory scans
• Retrieve hardware and firmware information
• Real-time tag events via stream (EPC, TID, RSSI)
• Optimized for performance with minimal battery impact
• Built with null safety

Prerequisites

• Flutter 3.0.0 or later
• Android 5.0 (API level 21) or later
• Urovo Android device with RFID capabilities

Installation

Add the following to your pubspec.yaml:

dependencies:
  flutter_urovo_rfid: ^0.1.0

Then run:

flutter pub get

Usage

Import the package

import 'package:flutter_urovo_rfid/flutter_urovo_rfid.dart';

Initialize the RFID Reader

// Power on and connect to the RFID module
final state = await FlutterUrovoRfid.openRfid();
print('RFID module state: $state');

Listen for Tag Scans

// Subscribe to tag events
final subscription = FlutterUrovoRfid.scanStream.listen((tag) {
  final epc = tag['epc'];  // Electronic Product Code
  final tid = tag['tid'];  // Tag ID
  final rssi = tag['rssi'] as int;  // Signal strength
  
  print('Tag detected - EPC: $epc, TID: $tid, RSSI: $rssi');
});

// Start scanning
await FlutterUrovoRfid.startReading();

// Stop scanning
await FlutterUrovoRfid.stopReading();

// Don't forget to cancel the subscription when done
await subscription.cancel();

Single Inventory Scan

// Perform a single inventory scan
final tags = await FlutterUrovoRfid.singleInventory();
print('Found ${tags.length} tags: $tags');

Retrieve Hardware Information

final fwVersion = await FlutterUrovoRfid.getFirmwareVersion();
print('Firmware version: $fwVersion');

Clean Up

// Power off the RFID module when done
await FlutterUrovoRfid.closeRfid();

Example Usage

void initReader() async {
  // Power on and connect
  final state = await FlutterUrovoRfid.openRfid();
  print('RFID state: $state');

  // Listen to tag events
  FlutterUrovoRfid.scanStream.listen((event) {
    final epc = event['epc'];
    final tid = event['tid'];
    final rssi = event['rssi'];
    print('Tag: EPC=$epc TID=$tid RSSI=$rssi');
  });
}

void startScanning() async {
  await FlutterUrovoRfid.startReading();
}

API Reference

Methods

Method	Description	Returns
openRfid()	Powers on and initializes the RFID module	Future<String> - Status message
closeRfid()	Powers off the RFID module	Future<void>
startReading()	Starts continuous inventory scanning	Future<void>
stopReading()	Stops continuous inventory scanning	Future<void>
singleInventory()	Performs a single inventory scan	Future<List<Map<String, dynamic>>> - List of scanned tags
getFirmwareVersion()	Retrieves the firmware version	Future<String> - Firmware version string

Streams

Stream	Description	Event Type
scanStream	Stream of tag scan events	Map<String, dynamic> with keys: epc, tid, rssi

Error Handling

All methods may throw a PlatformException if the operation fails. Make sure to handle potential errors:

try {
  await FlutterUrovoRfid.openRfid();
} on PlatformException catch (e) {
  print('Failed to initialize RFID: ${e.message}');
}

Permissions

Add the following permissions to your AndroidManifest.xml:

<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

For Android 12 and above, you'll also need to add these to your AndroidManifest.xml:

<uses-permission android:name="android.permission.BLUETOOTH_SCAN"
    android:usesPermissionFlags="neverForLocation"
    tools:targetApi="s" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />

Troubleshooting

Common Issues

1. RFID module not initializing

   • Ensure the device has RFID capabilities
   • Check if the RFID module is properly connected
   • Verify that all required permissions are granted

2. No tags being detected

   • Ensure tags are within the reader's range
   • Check if the RFID antenna is properly connected
   • Verify that the correct frequency is being used for your tags

Android Setup

This plugin depends on the proprietary Urovo RFID SDK. To compile and run successfully, you must obtain the SDK JAR/AAR files from Urovo and place them into the plugin's android/src/main/libs directory (create it if it doesn't exist). The Gradle script is configured to include any .jar or .aar files found there.

Adding Urovo SDK

1. Obtain the Urovo RFID SDK (.aar or .jar files) from Urovo
2. Create the directory if it doesn't exist:

   mkdir -p android/src/main/libs

3. Copy the Urovo SDK files to android/src/main/libs/
4. The plugin will automatically include these files in the build

ProGuard/R8 Configuration

Because the Urovo SDK uses reflection and dynamic loading, ProGuard rules have been provided in android/proguard-rules.pro to preserve required classes. If you're using ProGuard or R8 in your app, make sure to include these rules.

Example App

See the example app in the example/ directory for a complete demonstration of how to use this plugin in a Flutter application.

Permissions

Add the following permissions to your AndroidManifest.xml:

<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

For Android 12 and above, you'll also need to add these to your AndroidManifest.xml:

<uses-permission android:name="android.permission.BLUETOOTH_SCAN"
    android:usesPermissionFlags="neverForLocation"
    tools:targetApi="s" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />

## Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

## License

This project is licensed under the MIT License - see the [LICENSE](LICENSE) file for details.

## Acknowledgments

- Urovo Technology Co., Ltd. for their Android RFID SDK
- The Flutter team for their excellent plugin system