uhf_rfid_scanner 3.0.0

Flutter plugin for UHF RFID handheld scanners. Supports NewLand MT93 and Urovo DT610. Features tag scanning, power control, and SGTIN-96 to EAN-13 decoding.

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:uhf_rfid_scanner/rfid.dart';
import 'dart:async';

void main() {
  runApp(const MyApp());
}

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      title: 'NewLand RFID Demo',
      theme: ThemeData(primarySwatch: Colors.blue, useMaterial3: true),
      home: const RfidScannerPage(),
    );
  }
}

class RfidScannerPage extends StatefulWidget {
  const RfidScannerPage({super.key});

  @override
  State<RfidScannerPage> createState() => _RfidScannerPageState();
}

class _RfidScannerPageState extends State<RfidScannerPage> {
  final _rfidPlugin = Rfid();

  bool _isConnected = false;
  bool _isScanning = false;

  final Map<String, UHFTag> _scannedTags = {}; // Key = EPC, avoids duplicates
  StreamSubscription? _streamSubscription;

  double _powerLevel = 30.0; // default 30 dBm

  @override
  void dispose() {
    _streamSubscription?.cancel();
    _rfidPlugin.stopScan();
    _rfidPlugin.disconnect();
    super.dispose();
  }

  Future<void> _connect() async {
    try {
      final success = await _rfidPlugin.connect();
      setState(() {
        _isConnected = success;
      });
      _showSnackbar(success ? "Connected to UHF Module" : "Connection Failed");
    } catch (e) {
      _showSnackbar("Error connecting: $e");
    }
  }

  Future<void> _disconnect() async {
    try {
      await _stopScan();
      final success = await _rfidPlugin.disconnect();
      setState(() {
        _isConnected = !success;
      });
      _showSnackbar("Disconnected");
    } catch (e) {
      _showSnackbar("Error disconnecting: $e");
    }
  }

  Future<void> _startScan() async {
    if (!_isConnected) {
      _showSnackbar("Please Connect First");
      return;
    }

    await _streamSubscription?.cancel();
    _streamSubscription = null;

    setState(() {
      _scannedTags.clear();
      _isScanning = true;
    });

    try {
      _streamSubscription = _rfidPlugin.onTagsRead.listen(
        (List<UHFTag> incomingTags) {
          print('incomingTags: ${incomingTags.length} tags received');
          setState(() {
            for (var tag in incomingTags) {
              _scannedTags[tag.epc] = tag;
            }
          });
        },
        onError: (error) {
          print('Stream error: $error');
          _showSnackbar("Stream error: $error");
        },
      );

      final success = await _rfidPlugin.startScan();
      if (!success) {
        setState(() => _isScanning = false);
        _showSnackbar("Failed to start scan command");
      }
    } catch (e) {
      setState(() => _isScanning = false);
      _showSnackbar("Error starting scan: $e");
    }
  }

  Future<void> _stopScan() async {
    try {
      await _rfidPlugin.stopScan();
      await _streamSubscription?.cancel();
      setState(() {
        _isScanning = false;
      });
    } catch (e) {
      _showSnackbar("Error stopping scan: $e");
    }
  }

  Future<void> _setPower(double value) async {
    if (!_isConnected) return;

    try {
      // SDK expects 3000 for 30dBm
      int powerInt = (value * 100).toInt();
      await _rfidPlugin.setPower(powerInt, powerInt);
      setState(() {
        _powerLevel = value;
      });
      _showSnackbar("Power set to $powerInt ($value dBm)");
    } catch (e) {
      _showSnackbar("Failed to set power: $e");
    }
  }

  void _clearData() {
    setState(() {
      _scannedTags.clear();
    });
  }

  void _showSnackbar(String message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(message),
        duration: const Duration(milliseconds: 800),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('MT93-U RFID Scanner'),
        actions: [
          IconButton(
            icon: const Icon(Icons.delete_sweep),
            onPressed: _clearData,
            tooltip: "Clear Data",
          ),
        ],
      ),
      body: Column(
        children: [
          _buildControlPanel(),

          const Divider(height: 1),

          Container(
            padding: const EdgeInsets.symmetric(vertical: 8, horizontal: 16),
            color: Colors.grey[200],
            child: Row(
              mainAxisAlignment: MainAxisAlignment.spaceBetween,
              children: [
                Text(
                  "Total Tags: ${_scannedTags.length}",
                  style: const TextStyle(
                    fontWeight: FontWeight.bold,
                    fontSize: 16,
                  ),
                ),
                if (_isScanning)
                  const Row(
                    children: [
                      SizedBox(
                        width: 12,
                        height: 12,
                        child: CircularProgressIndicator(strokeWidth: 2),
                      ),
                      SizedBox(width: 8),
                      Text(
                        "Scanning...",
                        style: TextStyle(color: Colors.green),
                      ),
                    ],
                  )
                else
                  const Text("Idle", style: TextStyle(color: Colors.red)),
              ],
            ),
          ),

          Expanded(
            child: _scannedTags.isEmpty
                ? const Center(child: Text("No tags scanned"))
                : ListView.builder(
                    itemCount: _scannedTags.length,
                    itemBuilder: (context, index) {
                      String key = _scannedTags.keys.elementAt(index);
                      UHFTag tag = _scannedTags[key]!;
                      return _buildTagTile(tag);
                    },
                  ),
          ),
        ],
      ),
    );
  }

  Widget _buildControlPanel() {
    return Card(
      margin: const EdgeInsets.all(8),
      elevation: 2,
      child: Padding(
        padding: const EdgeInsets.all(12.0),
        child: Column(
          children: [
            Row(
              children: [
                Expanded(
                  child: ElevatedButton.icon(
                    onPressed: _isConnected ? null : _connect,
                    icon: const Icon(Icons.bluetooth_connected),
                    label: const Text("Connect"),
                    style: ElevatedButton.styleFrom(
                      backgroundColor: Colors.blueAccent,
                      foregroundColor: Colors.white,
                    ),
                  ),
                ),
                const SizedBox(width: 10),
                Expanded(
                  child: OutlinedButton.icon(
                    onPressed: _isConnected ? _disconnect : null,
                    icon: const Icon(Icons.bluetooth_disabled),
                    label: const Text("Disconnect"),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 10),

            Row(
              children: [
                Expanded(
                  child: ElevatedButton.icon(
                    onPressed: (_isConnected && !_isScanning)
                        ? _startScan
                        : null,
                    icon: const Icon(Icons.play_arrow),
                    label: const Text("Start Scan"),
                    style: ElevatedButton.styleFrom(
                      backgroundColor: Colors.green,
                      foregroundColor: Colors.white,
                    ),
                  ),
                ),
                const SizedBox(width: 10),
                Expanded(
                  child: ElevatedButton.icon(
                    onPressed: (_isConnected && _isScanning) ? _stopScan : null,
                    icon: const Icon(Icons.stop),
                    label: const Text("Stop Scan"),
                    style: ElevatedButton.styleFrom(
                      backgroundColor: Colors.redAccent,
                      foregroundColor: Colors.white,
                    ),
                  ),
                ),
              ],
            ),

            const SizedBox(height: 10),

            Row(
              children: [
                const Text(
                  "Power: ",
                  style: TextStyle(fontWeight: FontWeight.bold),
                ),
                Text("${_powerLevel.toInt()} dBm"),
                Expanded(
                  child: Slider(
                    value: _powerLevel,
                    min: 5,
                    max: 33,
                    divisions: 28,
                    label: "${_powerLevel.toInt()}",
                    onChanged: _isConnected
                        ? (val) => setState(() => _powerLevel = val)
                        : null,
                    onChangeEnd: (val) => _setPower(val),
                  ),
                ),
              ],
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildTagTile(UHFTag tag) {
    return Card(
      margin: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
      child: ListTile(
        leading: CircleAvatar(
          backgroundColor: _getRssiColor(tag.rssi),
          child: Text(
            "${tag.rssi}",
            style: const TextStyle(color: Colors.white, fontSize: 10),
          ),
        ),
        title: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            if (tag.ean != null)
              Row(
                children: [
                  const Icon(Icons.qr_code, size: 16, color: Colors.green),
                  const SizedBox(width: 4),
                  Text(
                    "EAN: ${tag.ean}",
                    style: const TextStyle(
                      fontWeight: FontWeight.bold,
                      fontSize: 15,
                      color: Colors.green,
                    ),
                  ),
                ],
              ),
            Text(
              tag.epc,
              style: TextStyle(
                fontFamily: 'monospace',
                fontWeight: FontWeight.bold,
                fontSize: tag.ean != null ? 11 : 14,
                color: tag.ean != null ? Colors.grey[600] : Colors.black,
              ),
            ),
          ],
        ),
        subtitle: tag.tid != null ? Text("TID: ${tag.tid}") : null,
        trailing: Container(
          padding: const EdgeInsets.all(8),
          decoration: BoxDecoration(
            color: Colors.grey[200],
            borderRadius: BorderRadius.circular(8),
          ),
          child: Column(
            mainAxisSize: MainAxisSize.min,
            children: [
              const Text("Count", style: TextStyle(fontSize: 10)),
              Text(
                "${tag.readCount}",
                style: const TextStyle(fontWeight: FontWeight.bold),
              ),
            ],
          ),
        ),
      ),
    );
  }

  Color _getRssiColor(int rssi) {
    double val = rssi.toDouble();
    if (val.abs() < 50) return Colors.green;
    if (val.abs() < 70) return Colors.orange;
    return Colors.red;
  }
}