flutter_bluetooth_classic_serial 1.0.2

flutter_bluetooth_classic_serial: ^1.0.2 copied to clipboard

example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:flutter_bluetooth_classic_serial/flutter_bluetooth_classic.dart';

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

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

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Bluetooth Classic Demo',
      theme: ThemeData(
        colorScheme: ColorScheme.fromSeed(seedColor: Colors.deepPurple),
        useMaterial3: true,
      ),
      home: const BluetoothClassicDemo(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  const MyHomePage({super.key, required this.title});

  // This widget is the home page of your application. It is stateful, meaning
  // that it has a State object (defined below) that contains fields that affect
  // how it looks.

  // This class is the configuration for the state. It holds the values (in this
  // case the title) provided by the parent (in this case the App widget) and
  // used by the build method of the State. Fields in a Widget subclass are
  // always marked "final".

  final String title;

  @override
  State<MyHomePage> createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      // This call to setState tells the Flutter framework that something has
      // changed in this State, which causes it to rerun the build method below
      // so that the display can reflect the updated values. If we changed
      // _counter without calling setState(), then the build method would not be
      // called again, and so nothing would appear to happen.
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    // This method is rerun every time setState is called, for instance as done
    // by the _incrementCounter method above.
    //
    // The Flutter framework has been optimized to make rerunning build methods
    // fast, so that you can just rebuild anything that needs updating rather
    // than having to individually change instances of widgets.
    return Scaffold(
      appBar: AppBar(
        // TRY THIS: Try changing the color here to a specific color (to
        // Colors.amber, perhaps?) and trigger a hot reload to see the AppBar
        // change color while the other colors stay the same.
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        // Here we take the value from the MyHomePage object that was created by
        // the App.build method, and use it to set our appbar title.
        title: Text(widget.title),
      ),
      body: Center(
        // Center is a layout widget. It takes a single child and positions it
        // in the middle of the parent.
        child: Column(
          // Column is also a layout widget. It takes a list of children and
          // arranges them vertically. By default, it sizes itself to fit its
          // children horizontally, and tries to be as tall as its parent.
          //
          // Column has various properties to control how it sizes itself and
          // how it positions its children. Here we use mainAxisAlignment to
          // center the children vertically; the main axis here is the vertical
          // axis because Columns are vertical (the cross axis would be
          // horizontal).
          //
          // TRY THIS: Invoke "debug painting" (choose the "Toggle Debug Paint"
          // action in the IDE, or press "p" in the console), to see the
          // wireframe for each widget.
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            const Text('You have pushed the button this many times:'),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headlineMedium,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: const Icon(Icons.add),
      ), // This trailing comma makes auto-formatting nicer for build methods.
    );
  }
}

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

  @override
  State<BluetoothClassicDemo> createState() => _BluetoothClassicDemoState();
}

class _BluetoothClassicDemoState extends State<BluetoothClassicDemo> {
  late FlutterBluetoothClassic _bluetooth;
  bool _isBluetoothAvailable = false;
  BluetoothConnectionState? _connectionState;
  List<BluetoothDevice> _pairedDevices = [];
  BluetoothDevice? _connectedDevice;
  String _receivedData = '';
  final TextEditingController _messageController = TextEditingController();

  @override
  void initState() {
    super.initState();
    _bluetooth = FlutterBluetoothClassic();
    _initBluetooth();
  }

  Future<void> _initBluetooth() async {
    try {
      bool isSupported = await _bluetooth.isBluetoothSupported();
      bool isEnabled = await _bluetooth.isBluetoothEnabled();
      setState(() {
        _isBluetoothAvailable = isSupported && isEnabled;
      });

      if (isSupported && isEnabled) {
        _loadPairedDevices();
        _listenToConnectionState();
        _listenToIncomingData();
      }
    } catch (e) {
      debugPrint('Error initializing Bluetooth: $e');
    }
  }

  Future<void> _loadPairedDevices() async {
    try {
      List<BluetoothDevice> devices = await _bluetooth.getPairedDevices();
      setState(() {
        _pairedDevices = devices;
      });
    } catch (e) {
      debugPrint('Error loading paired devices: $e');
    }
  }

  void _listenToConnectionState() {
    _bluetooth.onConnectionChanged.listen((state) {
      setState(() {
        _connectionState = state;
        if (state.isConnected) {
          // Find the connected device
          _connectedDevice = _pairedDevices.firstWhere(
            (device) => device.address == state.deviceAddress,
            orElse: () => BluetoothDevice(
              name: 'Unknown Device',
              address: state.deviceAddress,
              paired: false,
            ),
          );
        } else {
          _connectedDevice = null;
        }
      });
    });
  }

  void _listenToIncomingData() {
    _bluetooth.onDataReceived.listen((data) {
      setState(() {
        _receivedData += '${data.asString()}\n';
      });
    });
  }

  Future<void> _connectToDevice(BluetoothDevice device) async {
    try {
      await _bluetooth.connect(device.address);
    } catch (e) {
      debugPrint('Error connecting to device: $e');
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('Failed to connect: $e')));
      }
    }
  }

  Future<void> _disconnect() async {
    try {
      await _bluetooth.disconnect();
    } catch (e) {
      debugPrint('Error disconnecting: $e');
    }
  }

  Future<void> _sendMessage() async {
    if (_messageController.text.isNotEmpty &&
        _connectionState?.isConnected == true) {
      try {
        await _bluetooth.sendString(_messageController.text);
        _messageController.clear();
      } catch (e) {
        debugPrint('Error sending message: $e');
        if (mounted) {
          ScaffoldMessenger.of(
            context,
          ).showSnackBar(SnackBar(content: Text('Failed to send message: $e')));
        }
      }
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: Theme.of(context).colorScheme.inversePrimary,
        title: const Text('Bluetooth Classic Demo'),
      ),
      body: Padding(
        padding: const EdgeInsets.all(16.0),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            // Bluetooth Status
            Card(
              child: Padding(
                padding: const EdgeInsets.all(16.0),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      'Bluetooth Status',
                      style: Theme.of(context).textTheme.titleMedium,
                    ),
                    const SizedBox(height: 8),
                    Row(
                      children: [
                        Icon(
                          _isBluetoothAvailable
                              ? Icons.bluetooth
                              : Icons.bluetooth_disabled,
                          color: _isBluetoothAvailable
                              ? Colors.blue
                              : Colors.grey,
                        ),
                        const SizedBox(width: 8),
                        Text(
                          _isBluetoothAvailable ? 'Available' : 'Not Available',
                        ),
                      ],
                    ),
                    const SizedBox(height: 8),
                    Row(
                      children: [
                        Icon(
                          _connectionState?.isConnected == true
                              ? Icons.link
                              : Icons.link_off,
                          color: _connectionState?.isConnected == true
                              ? Colors.green
                              : Colors.red,
                        ),
                        const SizedBox(width: 8),
                        Text(_connectionState?.status ?? 'disconnected'),
                      ],
                    ),
                    if (_connectedDevice != null) ...[
                      const SizedBox(height: 8),
                      Text('Connected to: ${_connectedDevice!.name}'),
                      Text('Address: ${_connectedDevice!.address}'),
                    ],
                  ],
                ),
              ),
            ),

            const SizedBox(height: 16),

            // Paired Devices
            Expanded(
              flex: 2,
              child: Card(
                child: Padding(
                  padding: const EdgeInsets.all(16.0),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Row(
                        mainAxisAlignment: MainAxisAlignment.spaceBetween,
                        children: [
                          Text(
                            'Paired Devices',
                            style: Theme.of(context).textTheme.titleMedium,
                          ),
                          IconButton(
                            onPressed: _loadPairedDevices,
                            icon: const Icon(Icons.refresh),
                          ),
                        ],
                      ),
                      const SizedBox(height: 8),
                      Expanded(
                        child: _pairedDevices.isEmpty
                            ? const Center(
                                child: Text('No paired devices found'),
                              )
                            : ListView.builder(
                                itemCount: _pairedDevices.length,
                                itemBuilder: (context, index) {
                                  final device = _pairedDevices[index];
                                  final isConnected =
                                      _connectedDevice?.address ==
                                      device.address;
                                  return ListTile(
                                    leading: Icon(
                                      Icons.devices,
                                      color: isConnected ? Colors.green : null,
                                    ),
                                    title: Text(device.name),
                                    subtitle: Text(device.address),
                                    trailing: isConnected
                                        ? ElevatedButton(
                                            onPressed: _disconnect,
                                            child: const Text('Disconnect'),
                                          )
                                        : ElevatedButton(
                                            onPressed:
                                                _connectionState?.isConnected !=
                                                    true
                                                ? () => _connectToDevice(device)
                                                : null,
                                            child: const Text('Connect'),
                                          ),
                                  );
                                },
                              ),
                      ),
                    ],
                  ),
                ),
              ),
            ),

            const SizedBox(height: 16), // Message Section
            if (_connectionState?.isConnected == true) ...[
              Card(
                child: Padding(
                  padding: const EdgeInsets.all(16.0),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Text(
                        'Send Message',
                        style: Theme.of(context).textTheme.titleMedium,
                      ),
                      const SizedBox(height: 8),
                      Row(
                        children: [
                          Expanded(
                            child: TextField(
                              controller: _messageController,
                              decoration: const InputDecoration(
                                hintText: 'Enter message to send',
                                border: OutlineInputBorder(),
                              ),
                            ),
                          ),
                          const SizedBox(width: 8),
                          ElevatedButton(
                            onPressed: _sendMessage,
                            child: const Text('Send'),
                          ),
                        ],
                      ),
                    ],
                  ),
                ),
              ),
              const SizedBox(height: 16),
            ],

            // Received Data
            Expanded(
              flex: 1,
              child: Card(
                child: Padding(
                  padding: const EdgeInsets.all(16.0),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Row(
                        mainAxisAlignment: MainAxisAlignment.spaceBetween,
                        children: [
                          Text(
                            'Received Data',
                            style: Theme.of(context).textTheme.titleMedium,
                          ),
                          IconButton(
                            onPressed: () {
                              setState(() {
                                _receivedData = '';
                              });
                            },
                            icon: const Icon(Icons.clear),
                          ),
                        ],
                      ),
                      const SizedBox(height: 8),
                      Expanded(
                        child: Container(
                          width: double.infinity,
                          padding: const EdgeInsets.all(8.0),
                          decoration: BoxDecoration(
                            border: Border.all(color: Colors.grey),
                            borderRadius: BorderRadius.circular(4.0),
                          ),
                          child: SingleChildScrollView(
                            child: Text(
                              _receivedData.isEmpty
                                  ? 'No data received'
                                  : _receivedData,
                              style: const TextStyle(fontFamily: 'monospace'),
                            ),
                          ),
                        ),
                      ),
                    ],
                  ),
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }

  @override
  void dispose() {
    _messageController.dispose();
    super.dispose();
  }
}