flutter_mic_selector

A Flutter plugin for discovering and selecting Android microphone input devices for use with compatible audio and video recording packages.

This plugin is focused solely on microphone discovery and selection. It does not record audio. Use external packages such as record for actual recording.

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Features

• List all available Android microphone input devices
• Select a microphone by device ID
• Read the currently selected microphone
• Clear the selection and restore system default routing
• Listen for microphone connection and disconnection events
• Persist the selected device ID in native Android storage
• Check and request RECORD_AUDIO permission

Platform Support

Platform	Support
Android	✅ Supported
iOS	❌ Not supported
Web	❌ Not supported
Windows	❌ Not supported
macOS	❌ Not supported
Linux	❌ Not supported

Android Requirements

• minSdk: 21 (Android 5.0)
• Device discovery requires API 23+ (Android 6.0) — returns empty list on older versions
• Device connection events (AudioDeviceCallback) require API 23+

Installation

dependencies:
  flutter_mic_selector: ^0.3.0

Permission Setup

The plugin declares android.permission.RECORD_AUDIO in its own manifest. Your app must also request this permission at runtime before using microphone features:

import 'package:flutter_mic_selector/flutter_mic_selector.dart';

final micSelector = FlutterMicSelector.instance;

if (await micSelector.hasPermission()) {
  // Permission granted
} else {
  final granted = await micSelector.requestPermission();
  if (!granted) return; // Handle denial
}

For more control over permission flows, use the permission_handler package.

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Usage

Import

import 'package:flutter_mic_selector/flutter_mic_selector.dart';

Listing Microphones

final micSelector = FlutterMicSelector.instance;
final devices = await micSelector.getAvailableMicrophones();

for (final device in devices) {
  print('${device.name} (${device.type.label})');
}

Selecting a Microphone

final devices = await micSelector.getAvailableMicrophones();
if (devices.isNotEmpty) {
  await micSelector.selectMicrophone(devices.first);
  // or by ID:
  await micSelector.selectMicrophoneById(devices.first.id);
}

Reading the Selected Microphone

final selected = await micSelector.getSelectedMicrophone();
print(selected?.name ?? 'No device selected');

Clearing the Selection

await micSelector.clearSelectedMicrophone();
// System default routing is restored.

Listening for Device Changes

micSelector.microphoneDevicesChanged.listen((devices) {
  print('Devices changed: ${devices.length} microphone(s) available');
});

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Audio Recording Integration

Use the record package to record audio with your selected microphone:

import 'package:record/record.dart';

final micSelector = FlutterMicSelector.instance;

// Select a microphone
await micSelector.selectMicrophoneById('some-device-id');

// Start recording (Android will route audio based on the selection)
final recorder = AudioRecorder();
await recorder.start(const RecordConfig(), path: '/path/to/output.m4a');
// ... later ...
await recorder.stop();

Note: Audio routing to the selected microphone depends on Android's audio framework. The selected device is applied as a preference, not a guaranteed route for all recorder implementations.

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Video Recording Integration

The official Flutter camera package does not expose a public microphone device parameter. Video microphone selection depends on Android audio routing and device behavior, and may not work consistently across all devices.

The plugin does not currently mux separately recorded audio and video. For synchronized A/V recording, consider using the camera package's built-in audio capture.

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Model Reference

MicrophoneDevice

Field	Type	Description
id	String	Stable Android audio device ID
name	String	User-facing display name
type	MicrophoneType	Categorized device type
isInput	bool	Always true for microphones
isSelected	bool	Whether this is the currently selected device

MicrophoneType

Value	Description
builtIn	Built-in microphone (earpiece, speaker, or mic)
wiredHeadset	Wired headset, headphones, or line input
bluetooth	Bluetooth or BLE headset microphone
usb	USB microphone, headset, or accessory
telephony	Telephony microphone
unknown	Unknown or unsupported input type

Typed Exceptions

Exception	When thrown
MicrophoneNotFoundException	The requested device ID does not exist
MicrophoneSelectionException	Android rejected the selection
MicrophonePermissionException	RECORD_AUDIO permission is missing
UnsupportedMicrophoneException	Operation not supported on this platform

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Example Application

The example/ directory contains a working application that demonstrates:

1. Requesting microphone permission
2. Listing available microphones
3. Selecting a microphone
4. Displaying selected device information
5. Recording audio using the selected microphone (via record package)
6. Handling device connection/disconnection events

Run the example:

cd example
flutter run

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Contributing

Contributions are welcome, especially for adding support for platforms beyond Android. Please open an issue or pull request with your proposed approach.

License

MIT