BlueBreeze Flutter

BlueBreeze is a modern Bluetooth LE library for Flutter, wrapping the native BlueBreeze iOS and BlueBreeze Android SDKs behind a single Dart API. All the platform-specific work -- connection state machines, GATT callback correlation, per-device request queuing -- happens natively; from Dart you just observe state and await operations.

Reactive state -- adapter power, authorization, discovered devices, connection status, services, and characteristic data are all exposed as Streams you can listen to reactively.
Future-based operations -- connect, discover services, read, write, and subscribe/unsubscribe are all async calls with a built-in timeout enforced natively, instead of platform callbacks you have to correlate yourself.
Automatic per-device request queuing -- handled natively on both platforms, so you can fire off several operations on the same device without worrying about overlapping BLE requests.
Runtime permission handling built in -- authorizationStatus/authorizationRequest/ authorizationOpenSettings cover Android's runtime permissions and iOS's Bluetooth usage authorization behind one API.
Bluetooth SIG assigned numbers built in -- known company IDs, service UUIDs, and characteristic UUIDs are resolved automatically by the underlying native SDKs.
Hot reload aware -- handleHotReload() disconnects stale native connections so a Dart hot reload doesn't leave them orphaned during development.

Installation

flutter pub add bluebreeze

Requirements

Flutter 3.41.0+, Dart 3.11.0+
Android minSdk 21, compiled against API 36
iOS 13.0+
Declare the Bluetooth permissions each platform needs:

Android (android/app/src/main/AndroidManifest.xml):

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" android:maxSdkVersion="30" />
<uses-permission android:name="android.permission.BLUETOOTH" android:maxSdkVersion="30" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" android:maxSdkVersion="30" />
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" android:usesPermissionFlags="neverForLocation" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />

<uses-feature android:name="android.hardware.bluetooth_le" android:required="true" />

iOS (ios/Runner/Info.plist):

<key>NSBluetoothAlwaysUsageDescription</key>
<string>This app uses Bluetooth to connect to nearby devices.</string>

Quick start

import 'package:bluebreeze/bluebreeze.dart';

final manager = BBManager();

// Request authorization if needed, then start scanning once the adapter is on
if (manager.authorizationStatus != BBAuthorization.authorized) {
  manager.authorizationRequest();
}

manager.stateStream.listen((state) {
  if (state == BBState.poweredOn) {
    manager.scanStart();
  }
});

// Observe scan results
manager.scanResultsStream.listen((result) {
  print('${result.name ?? 'Unknown device'} ${result.rssi}');
});

// Connect, discover, and talk to a device
Future<void> connectToFirstDevice() async {
  if (manager.devices.isEmpty) return;
  final device = manager.devices.values.first;

  await device.connect();
  await device.discoverServices();

  for (final service in device.services) {
    for (final characteristic in service.characteristics) {
      if (characteristic.properties.contains(BBCharacteristicProperty.read)) {
        final data = await characteristic.read();
        print('${characteristic.id} $data');
      }
    }
  }

  await device.disconnect();
}

See example for a full app built on top of BlueBreeze.

Documentation

The public API is documented with dartdoc directly in the source under lib -- hover any exported member in your editor to see it, or browse it there directly.

License

BlueBreeze is available under the MIT license. See LICENSE for details.