Audio Device Detection

A Flutter plugin to detect connected audio output devices (Bluetooth, Wired Headset, Built-in Speaker, etc.) and monitor connection state changes on Android and iOS.

Features

• Get a list of currently connected audio devices (Bluetooth, Wired, Speaker, etc.).
• Listen to real-time audio output connection/disconnection events (Stream).
• Provide device details including name and protocol type (A2DP, HFP, WIRED, SPEAKER, etc.).

Setup

Before using the plugin, you need to add the necessary permissions for each platform.

Android

Add the following permissions to your android/app/src/main/AndroidManifest.xml. These permissions are required to discover Bluetooth devices and check their connection status.

Note: Since this plugin targets Android 12 (API 31) and above, the BLUETOOTH_CONNECT permission is mandatory.

<manifest xmlns:android="[http://schemas.android.com/apk/res/android](http://schemas.android.com/apk/res/android)"
    package="com.example.your_app_name">

    <uses-permission android:name="android.permission.BLUETOOTH_CONNECT" />

    <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.MODIFY_AUDIO_SETTINGS" />

    <application
        ...>
    </application>
</manifest>

iOS

Add the following key to your ios/Runner/Info.plist. This description will be displayed when the app requests Bluetooth permissions from the user.

<key>NSBluetoothAlwaysUsageDescription</key>
<string>Need permission to detect bluetooth audio devices.</string>

Usage

Once the setup is complete, you can use the plugin in your Dart code as follows.

Requesting Permissions

You must request permission from the user before using the features. We recommend using the permission_handler package.

import 'package:permission_handler/permission_handler.dart';

Future<void> requestPermission() async {
final status = await Permission.bluetoothConnect.request();
  if (status.isGranted) {
    print("Bluetooth permission granted.");
  } else {
    print("Bluetooth permission denied.");
  }
}

Get Connected Devices

import 'package:audio_device_detection/audio_device_detection.dart';

Future<void> getDevices() async {
  List<AudioDevice> devices = await AudioDeviceDetection.instance.getConnectedDevices();
  for (var device in devices) {
    print('Device: ${device.name}, Protocol: ${device.protocol}');
  }
}

Listen to Device Connection Changes

Subscribe to the onDeviceStateChanged stream to receive real-time connection and disconnection events.

import 'dart:async';
import 'package:audio_device_detection/audio_device_detection.dart';

// Variable to manage stream subscription
StreamSubscription<AudioDevice>? deviceStateSubscription;

void listenToDeviceChanges() {
  deviceStateSubscription = AudioDeviceDetection.instance.onDeviceStateChanged.listen((AudioDevice device) {
      if (device.isConnected) {
        print('${device.name} connected. (${device.protocol})');
      } else {
        print('${device.name} disconnected');
      }
  });
}

// Don't forget to cancel the subscription when the widget is disposed.
@override
void dispose() {
  deviceStateSubscription?.cancel();
  super.dispose();
}