Ble Peripheral

Ble peripheral is a Flutter plugin that allows you to use your device as Bluetooth Low Energy (BLE) peripheral

This is an OS-independent plugin for creating a BLE Generic Attribute Profile (GATT) server to broadcast user-defined services and characteristics. This is particularly useful when prototyping and testing servers on different devices with the goal of ensuring that expected behavior matches across all systems.

Setup

Android

Add the following permissions to your AndroidManifest.xml file:

<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />
<uses-permission android:name="android.permission.BLUETOOTH_ADVERTISE" />
<uses-permission android:name="android.permission.BLUETOOTH_SCAN" />

IOS/Macos

Add permission in info.plist

<key>NSBluetoothAlwaysUsageDescription</key>
<string>For advertise as ble peripheral</string>

For MacOS, make sure to enable bluetooth from xcode

Windows

Requires Nuget for Winrt api's

Usage

Make sure to initialize first

final BlePeripheral blePeripheral = BlePeripheral();
await blePeripheral.initialize();

Add services

UUID serviceBattery = UUID(value: "0000180F-0000-1000-8000-00805F9B34FB");
UUID characteristicBatteryLevel = UUID(value: "00002A19-0000-1000-8000-00805F9B34FB");

BleService batteryService = BleService(
      uuid: serviceBattery,
      primary: true,
      characteristics: [
        BleCharacteristic(
          uuid: characteristicBatteryLevel,
          properties: [
            CharacteristicProperties.read.index,
            CharacteristicProperties.notify.index
          ],
          value: null,
          descriptors: [],
          permissions: [
            AttributePermissions.readable.index
          ],
        ),
      ],
    );

List<BleService> services = [batteryService];
await blePeripheral.addServices(services);

Start advertising

blePeripheral.startAdvertising(services,"TestDevice");

Stop advertising

blePeripheral.stopAdvertising();

Ble communication

Create a class which extends BleCallback

class PeripheralCallbackHandler extends BleCallback {
  @override
  void onAdvertisingStarted(String? error) {
    print("advertisingStarted: $error");
  }

  @override
  void onBleStateChange(bool state) {
    print("BleState: $state");
  };

  @override
  void onServiceAdded(BleService service, String? error) {
    print("Service added: ${service.uuid.value}");
  }

  @override
  void onWriteRequest(BleCharacteristic characteristic, int offset, Uint8List? value) {
    print("characteristic WriteRequires: ${characteristic.uuid.value}");
  }

  @override
  ReadRequestResult? onReadRequest(BleCharacteristic characteristic, int offset, Uint8List? value) {
    print("characteristic ReadRequest: ${characteristic.uuid.value}");
    // Reply a response to readRequest, return null to respond as failure
    return ReadRequestResult(
      value: Uint8List.fromList([]),
      offset: 0,
    );
  }

 
  @override
  void onCharacteristicSubscriptionChange(BleCentral central, BleCharacteristic characteristic, bool isSubscribed) {
    print("characteristic SubscriptionChange: ${characteristic.uuid.value}");
  }
  

  /// IOS/MacOS only  
  @override
  void onSubscribe(BleCentral bleCentral, BleCharacteristic characteristic){
     /// called on apple, when central subscribe to characteristic
  }
      
  /// IOS/MacOS only 
  @override
  void onUnsubscribe(BleCentral bleCentral, BleCharacteristic characteristic) {
    /// called on apple, when central unSubscribe from characteristic
  }


  /// Android only 
  @override
  void onConnectionStateChange(BleCentral central, bool connected) {
    /// called on android when central successfully connected
  }

  /// Android only 
  @override
  void onBondStateChange(BleCentral central, int bondState) {
    /// called on android when central successfully paired
    print("onBondStateChange: ${central.uuid.value} : ${BondState.fromInt(bondState)}");
  }
}

Setup this class to receive updates

blePeripheral.setBleCallback(PeripheralCallbackHandler());

TODO

Complete windows implementation

Note

Still under development, api's might change, this is just the initial version, feel free to contribute or report any bug!