Change Audio Output Device - Flutter

During the room at any point a participant wishes to switch his/her output audio like from headphones to speaker, it can be done using the below mentioned methods.

important

On Android and iOS, the microphone and the speaker share a single audio route, so setAudioDevice() changes both. To choose the microphone, see Change Audio Input Device.

getMics()

• The VideoSDK.getMics() method lists all the audio devices you can switch to, as a list of MicrophoneDeviceInfo objects. Each one is an audio route.

• The MicrophoneDeviceInfo object will contain the deviceId, kind and label for the device.

• On Android, the devices are SPEAKER_PHONE, EARPIECE, WIRED_HEADSET and BLUETOOTH, as each one is connected. On iOS, the list holds Speaker and the microphones you can use, such as iPhone Microphone, Headphones for a wired headset, or the name of a Bluetooth headset.

setAudioDevice()

• After selecting the desired device, you can switch the audio output by passing the corresponding MicrophoneDeviceInfo object to the setAudioDevice() method of the Room.

• The microphone stays muted or unmuted as it was.

• You can call setAudioDevice() before you join. The room uses that device when you join.

• setAudioDevice() returns a Future that throws a VideoSDKError if the switch fails.

• VideoSDK.getSelectedAudioDevice() returns the audio device in use, from join on, including the one you pick with setAudioDevice() or changeMic(). It is null before join.

import 'package:flutter/material.dart';
import 'package:videosdk/videosdk.dart';

class RoomScreen extends StatefulWidget {
  const RoomScreen({Key? key}) : super(key: key);

  @override
  _RoomScreenState createState() => _RoomScreenState();
}

class _RoomScreenState extends State<RoomScreen> {
  late Room _room;
  List<MicrophoneDeviceInfo> speakers = [];

  @override
  void initState() {
    super.initState();
    fetchSpeakers();
  }

  void fetchSpeakers() async {
    List<MicrophoneDeviceInfo>? audioDevices = await VideoSDK.getMics();
    setState(() => speakers = audioDevices ?? []);
  }

  Future<void> setAudioDevice(MicrophoneDeviceInfo device) async {
    try {
      await _room.setAudioDevice(device);
    } on VideoSDKError catch (error) {
      print("setAudioDevice failed: ${error.code} ${error.name}");
    }
  }

  @override
  Widget build(BuildContext context) {
    return Column(children: [
      ElevatedButton(
          child: const Text("Change Audio Device"),
          onPressed: () {
            showDialog(
              context: context,
              builder: (context) => AlertDialog(
                title: const Text("Select Audio Device"),
                content: Column(
                  mainAxisAlignment: MainAxisAlignment.center,
                  mainAxisSize: MainAxisSize.min,
                  children: <Widget>[
                    SingleChildScrollView(
                      reverse: true,
                      child: speakers.isNotEmpty
                          ? Column(
                              children: speakers
                                  .map(
                                    (device) => ElevatedButton(
                                      child: Text(device.label),
                                      onPressed: () async {
                                        Navigator.pop(context);
                                        await setAudioDevice(device);
                                      },
                                    ),
                                  )
                                  .toList(),
                            )
                          : const Text("No Speaker Devices found."),
                    )
                  ],
                ),
              ),
            );
          }),
    ]);
  }
}

setAudioDeviceChangeListener()

• The audio route changes on its own when a headset or Bluetooth device connects or disconnects.

• Pass a listener to room.setAudioDeviceChangeListener() to hear about it. It receives the device now in use and every device available.

• Pass null to stop listening.

_room.setAudioDeviceChangeListener(
  (MicrophoneDeviceInfo? selectedDevice, List<MicrophoneDeviceInfo> devices) {
    print("Audio now on ${selectedDevice?.label}");
    setState(() => speakers = devices);
  },
);

API Reference

The API references for all the methods and events utilised in this guide are provided below.

• getMics()
• setAudioDevice()
• setAudioDeviceChangeListener()
• getSelectedAudioDevice()