Add headphone controls support for media flyout

FluentFlyoutWPF/Classes/ExternalVolumeMonitor.cs

@@ -0,0 +1,99 @@
+// Copyright (c) 2024-2026 The FluentFlyout Authors
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+using NAudio.CoreAudioApi;
+
+namespace FluentFlyoutWPF.Classes;
+
+public class ExternalVolumeMonitor : IDisposable
+{
+    private static readonly NLog.Logger Logger = NLog.LogManager.GetCurrentClassLogger();
+
+    private readonly int _localInputGracePeriodMs;
+    private MMDevice? _device;
+    private float _lastVolume;
+    private bool _lastMuted;
+
+    public event EventHandler? ExternalVolumeChanged;
+
+    public ExternalVolumeMonitor(int localInputGracePeriodMs)
+    {
+        _localInputGracePeriodMs = localInputGracePeriodMs;
+
+        AudioDeviceMonitor.Instance.DefaultDeviceChanged += OnDefaultDeviceChanged;
+        AttachDevice(AudioDeviceMonitor.Instance.GetDefaultRenderDevice());
+    }
+
+    private void AttachDevice(MMDevice? device)
+    {
+        DetachDevice();
+
+        if (device == null)
+            return;
+
+        try
+        {
+            _lastVolume = device.AudioEndpointVolume.MasterVolumeLevelScalar;
+            _lastMuted = device.AudioEndpointVolume.Mute;
+            device.AudioEndpointVolume.OnVolumeNotification += OnVolumeNotification;
+            _device = device;
+        }
+        catch (Exception ex)
+        {
+            Logger.Error(ex, "Failed to watch volume of device {0}", device.FriendlyName);
+            device.Dispose();
+        }
+    }
+
+    private void DetachDevice()
+    {
+        if (_device == null)
+            return;
+
+        try
+        {
+            _device.AudioEndpointVolume.OnVolumeNotification -= OnVolumeNotification;
+            _device.Dispose();
+        }
+        catch (Exception ex)
+        {
+            Logger.Error(ex, "Failed to stop watching device volume");
+        }
+        finally
+        {
+            _device = null;
+        }
+    }
+
+    private void OnDefaultDeviceChanged(object? sender, DefaultDeviceChangedEventArgs e)
+    {
+        System.Windows.Application.Current.Dispatcher.InvokeAsync(() =>
+        {
+            AttachDevice(AudioDeviceMonitor.Instance.GetDeviceById(e.DeviceId));
+        });
+    }
+
+    private void OnVolumeNotification(AudioVolumeNotificationData data)
+    {
+        // the volume mixer writes the same volume back when syncing
+        bool changed = MathF.Abs(data.MasterVolume - _lastVolume) > 0.001f || data.Muted != _lastMuted;
+        _lastVolume = data.MasterVolume;
+        _lastMuted = data.Muted;
+
+        if (!changed || LocalInputDetector.HadInputWithin(_localInputGracePeriodMs))
+            return;
+
+#if DEBUG
+        Logger.Debug("External volume change detected: {0:P0}, muted: {1}", data.MasterVolume, data.Muted);
+#endif
+        ExternalVolumeChanged?.Invoke(this, EventArgs.Empty);
+    }
+
+    public void Dispose()
+    {
+        AudioDeviceMonitor.Instance.DefaultDeviceChanged -= OnDefaultDeviceChanged;
+        DetachDevice();
+
+        GC.SuppressFinalize(this);
+    }
+}

FluentFlyoutWPF/Classes/LocalInputDetector.cs

@@ -0,0 +1,20 @@
+// Copyright (c) 2024-2026 The FluentFlyout Authors
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+using System.Runtime.InteropServices;
+using static FluentFlyout.Classes.NativeMethods;
+
+namespace FluentFlyoutWPF.Classes;
+
+internal static class LocalInputDetector
+{
+    public static bool HadInputWithin(int milliseconds)
+    {
+        var info = new LASTINPUTINFO { cbSize = (uint)Marshal.SizeOf<LASTINPUTINFO>() };
+        if (!GetLastInputInfo(ref info))
+            return false;
+
+        uint elapsed = unchecked((uint)Environment.TickCount - info.dwTime);
+        return elapsed < milliseconds;
+    }
+}

FluentFlyoutWPF/Classes/NativeMethods.cs

@@ -69,6 +69,7 @@ public static partial class NativeMethods
     internal const int APPCOMMAND_MEDIA_STOP = 13;
     internal const int APPCOMMAND_MEDIA_PLAY_PAUSE = 14;
     internal const int FAPPCOMMAND_KEY = 0x0000;
+    internal const int FAPPCOMMAND_OEM = 0x1000;
 
     #endregion
 
@@ -215,6 +216,13 @@ internal struct WindowCompositionAttributeData
         public int SizeOfData;
     }
 
+    [StructLayout(LayoutKind.Sequential)]
+    internal struct LASTINPUTINFO
+    {
+        public uint cbSize;
+        public uint dwTime;
+    }
+
     #endregion
 
     #region Delegates
@@ -342,6 +350,10 @@ internal struct WindowCompositionAttributeData
 
     [LibraryImport("user32.dll", SetLastError = true)]
     internal static partial IntPtr GetForegroundWindow();
+
+    [LibraryImport("user32.dll")]
+    [return: MarshalAs(UnmanagedType.Bool)]
+    internal static partial bool GetLastInputInfo(ref LASTINPUTINFO plii);
     #endregion
 
     #region gdi32.dll

FluentFlyoutWPF/MainWindow.HeadsetControls.cs

@@ -0,0 +1,120 @@
+// Copyright (c) 2024-2026 The FluentFlyout Authors
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+using FluentFlyout.Classes.Settings;
+using FluentFlyoutWPF.Classes;
+using Windows.Media.Control;
+using static FluentFlyout.Classes.NativeMethods;
+using static WindowsMediaController.MediaManager;
+
+namespace FluentFlyoutWPF;
+
+public partial class MainWindow
+{
+    private const int LocalInputGracePeriodMs = 500;
+
+    private ExternalVolumeMonitor? _externalVolumeMonitor;
+    private readonly Dictionary<string, GlobalSystemMediaTransportControlsSessionPlaybackStatus> _lastPlaybackStatuses = [];
+
+    private static bool HeadsetControlsEnabled => SettingsManager.Current.MediaFlyoutHeadsetControlsEnabled;
+
+    private void InitializeHeadsetControls()
+    {
+        foreach (var session in mediaManager.CurrentMediaSessions.Values)
+            UpdateLastPlaybackStatus(session);
+
+        mediaManager.OnAnyPlaybackStateChanged += HeadsetControls_OnPlaybackStateChanged;
+        mediaManager.OnAnySessionClosed += HeadsetControls_OnSessionClosed;
+
+        _externalVolumeMonitor = new ExternalVolumeMonitor(LocalInputGracePeriodMs);
+        _externalVolumeMonitor.ExternalVolumeChanged += HeadsetControls_OnExternalVolumeChanged;
+    }
+
+    private void DisposeHeadsetControls()
+    {
+        mediaManager.OnAnyPlaybackStateChanged -= HeadsetControls_OnPlaybackStateChanged;
+        mediaManager.OnAnySessionClosed -= HeadsetControls_OnSessionClosed;
+
+        if (_externalVolumeMonitor != null)
+        {
+            _externalVolumeMonitor.ExternalVolumeChanged -= HeadsetControls_OnExternalVolumeChanged;
+            _externalVolumeMonitor.Dispose();
+            _externalVolumeMonitor = null;
+        }
+    }
+
+    private static bool IsHeadsetAppCommand(int device)
+    {
+        if (device != FAPPCOMMAND_OEM)
+            return false;
+
+#if DEBUG
+        Logger.Debug("App command received from OEM device, headset controls enabled: " + HeadsetControlsEnabled);
+#endif
+        return HeadsetControlsEnabled;
+    }
+
+    private void HeadsetControls_OnExternalVolumeChanged(object? sender, EventArgs e)
+    {
+        if (!HeadsetControlsEnabled)
+            return;
+
+        Dispatcher.BeginInvoke(() =>
+        {
+            if (!SettingsManager.Current.MediaFlyoutVolumeKeysExcluded)
+                TryShowMediaFlyoutDebounced();
+
+            ShowVolumeFlyout();
+        });
+    }
+
+    private void HeadsetControls_OnPlaybackStateChanged(MediaSession mediaSession, GlobalSystemMediaTransportControlsSessionPlaybackInfo? playbackInfo = null)
+    {
+        var (previousStatus, currentStatus) = UpdateLastPlaybackStatus(mediaSession, playbackInfo);
+
+        if (!HeadsetControlsEnabled)
+            return;
+
+        bool isPlayPauseToggle =
+            (previousStatus == GlobalSystemMediaTransportControlsSessionPlaybackStatus.Playing && currentStatus == GlobalSystemMediaTransportControlsSessionPlaybackStatus.Paused) ||
+            (previousStatus == GlobalSystemMediaTransportControlsSessionPlaybackStatus.Paused && currentStatus == GlobalSystemMediaTransportControlsSessionPlaybackStatus.Playing);
+
+        if (!isPlayPauseToggle || LocalInputDetector.HadInputWithin(LocalInputGracePeriodMs))
+            return;
+
+        Dispatcher.BeginInvoke(() =>
+        {
+            if (GetActiveMediaSession()?.Id != mediaSession.Id)
+                return;
+
+#if DEBUG
+            Logger.Debug("Play/pause without key press detected: " + mediaSession.Id + " " + currentStatus);
+#endif
+            TryShowMediaFlyoutDebounced();
+        });
+    }
+
+    private void HeadsetControls_OnSessionClosed(MediaSession mediaSession)
+    {
+        lock (_lastPlaybackStatuses)
+            _lastPlaybackStatuses.Remove(mediaSession.Id);
+    }
+
+    private (GlobalSystemMediaTransportControlsSessionPlaybackStatus? Previous, GlobalSystemMediaTransportControlsSessionPlaybackStatus? Current)
+        UpdateLastPlaybackStatus(MediaSession mediaSession, GlobalSystemMediaTransportControlsSessionPlaybackInfo? playbackInfo = null)
+    {
+        // sometimes mediaSession.ControlSession can be null
+        var currentStatus = playbackInfo?.PlaybackStatus ?? mediaSession.ControlSession?.GetPlaybackInfo()?.PlaybackStatus;
+        if (currentStatus == null)
+            return (null, null);
+
+        lock (_lastPlaybackStatuses)
+        {
+            GlobalSystemMediaTransportControlsSessionPlaybackStatus? previousStatus =
+                _lastPlaybackStatuses.TryGetValue(mediaSession.Id, out var lastStatus) ? lastStatus : null;
+
+            _lastPlaybackStatuses[mediaSession.Id] = currentStatus.Value;
+            return (previousStatus, currentStatus);
+        }
+    }
+}

FluentFlyoutWPF/MainWindow.xaml.cs

@@ -183,6 +183,8 @@ public MainWindow()
         mediaManager.OnAnyTimelinePropertyChanged += MediaManager_OnAnyTimelinePropertyChanged;
         mediaManager.OnAnySessionClosed += MediaManager_OnAnySessionClosed;
 
+        InitializeHeadsetControls();
+
         WM_TASKBARCREATED = RegisterWindowMessage("TaskbarCreated");
         WM_SHELLHOOK = RegisterWindowMessage("SHELLHOOK");
         RegisterShellHookWindow(new WindowInteropHelper(this).Handle);
@@ -1529,6 +1531,8 @@ private void CleanupResources()
             mediaManager.OnAnyTimelinePropertyChanged -= MediaManager_OnAnyTimelinePropertyChanged;
             mediaManager.OnAnySessionClosed -= MediaManager_OnAnySessionClosed;
 
+            DisposeHeadsetControls();
+
             // dispose managed resources
             _positionTimer?.Change(Timeout.Infinite, Timeout.Infinite);
             _positionTimer?.Dispose();
@@ -1742,8 +1746,9 @@ private nint WndProc(nint hwnd, int msg, nint wParam, nint lParam, ref bool hand
                 return 0;
 
             bool isKeyCommand = device == FAPPCOMMAND_KEY;
+            bool isHeadsetCommand = IsHeadsetAppCommand(device);
 
-            if (!isKeyCommand)
+            if (!isKeyCommand && !isHeadsetCommand)
                 return 0;
 
             bool result = false;

FluentFlyoutWPF/Pages/MediaFlyoutPage.xaml

@@ -33,6 +33,7 @@
                 <RowDefinition Height="Auto" />
                 <RowDefinition Height="Auto" />
                 <RowDefinition Height="Auto" />
+                <RowDefinition Height="Auto" />
             </Grid.RowDefinitions>
             <StackPanel Grid.Row="0" Orientation="Horizontal" Margin="0,0,0,24">
                 <Border CornerRadius="10" ClipToBounds="True" Width="164" Height="98">
@@ -166,7 +167,7 @@
                 </ui:CardControl.Header>
                 <ui:ToggleSwitch Name="PauseOtherSessionsEnabledSwitch" IsChecked="{Binding PauseOtherSessionsEnabled, Mode=TwoWay}" />
             </ui:CardControl>
-            <ui:CardControl x:Name="MediaFlyoutExcludeVolumeTitleCard" Tag="Indexable" Grid.Row="15" Icon="{ui:SymbolIcon SpeakerOff24}" Margin="0,0,0,76">
+            <ui:CardControl x:Name="MediaFlyoutExcludeVolumeTitleCard" Tag="Indexable" Grid.Row="15" Icon="{ui:SymbolIcon SpeakerOff24}" Margin="0,0,0,3">
                 <ui:CardControl.Header>
                     <StackPanel Orientation="Vertical">
                         <TextBlock Text="{DynamicResource MediaFlyoutExcludeVolumeTitle}" FontSize="14" FontWeight="Regular" VerticalAlignment="Center" />
@@ -175,6 +176,15 @@
                 </ui:CardControl.Header>
                 <ui:ToggleSwitch Name="MediaFlyoutVolumeKeysExcludedSwitch" IsChecked="{Binding MediaFlyoutVolumeKeysExcluded, Mode=TwoWay}" />
             </ui:CardControl>
+            <ui:CardControl x:Name="MediaFlyoutHeadsetControlsTitleCard" Tag="Indexable" Grid.Row="16" Icon="{ui:SymbolIcon Headphones24}" Margin="0,0,0,76">
+                <ui:CardControl.Header>
+                    <StackPanel Orientation="Vertical">
+                        <TextBlock Text="{DynamicResource MediaFlyoutHeadsetControlsTitle}" FontSize="14" FontWeight="Regular" VerticalAlignment="Center" />
+                        <TextBlock Text="{DynamicResource MediaFlyoutHeadsetControlsDescription}" FontSize="12" Opacity="0.5" />
+                    </StackPanel>
+                </ui:CardControl.Header>
+                <ui:ToggleSwitch Name="MediaFlyoutHeadsetControlsEnabledSwitch" IsChecked="{Binding MediaFlyoutHeadsetControlsEnabled, Mode=TwoWay}" />
+            </ui:CardControl>
         </Grid>
     </StackPanel>
 </Page>

FluentFlyoutWPF/Resources/Localization/Dictionary-en-US.xaml

@@ -14,6 +14,8 @@
     <System:String x:Key="TextBlockText3">Display a flyout when you press a media key</System:String>
     <System:String x:Key="MediaFlyoutExcludeVolumeTitle">Exclude Volume Keys</System:String>
     <System:String x:Key="MediaFlyoutExcludeVolumeDescription">Do not display the flyout when pressing volume up/down/mute</System:String>
+    <System:String x:Key="MediaFlyoutHeadsetControlsTitle">Headphone Controls</System:String>
+    <System:String x:Key="MediaFlyoutHeadsetControlsDescription">Also display the flyout when using the media or volume controls on Bluetooth headphones and other external devices</System:String>
     <System:String x:Key="TextBlockText2">Choose from a preset of modern background blur styles</System:String>
     <System:String x:Key="BackgroundBlurOption1" xml:space="preserve"> None</System:String>
     <System:String x:Key="BackgroundBlurOption2" xml:space="preserve"> Style 1 (Cover Glow)</System:String>

FluentFlyoutWPF/ViewModels/UserSettings.cs

@@ -241,6 +241,12 @@ public string LockKeysDurationText
     [ObservableProperty]
     public partial bool MediaFlyoutVolumeKeysExcluded { get; set; }
 
+    /// <summary>
+    /// Display media flyout when media or volume is changed from headphones or other external devices
+    /// </summary>
+    [ObservableProperty]
+    public partial bool MediaFlyoutHeadsetControlsEnabled { get; set; }
+
     /// <summary>
     /// Use symbol-style tray icon
     /// </summary>
@@ -729,6 +735,7 @@ public UserSettings()
         MediaFlyoutEnabled = true;
         MediaFlyoutAlwaysDisplay = false;
         MediaFlyoutVolumeKeysExcluded = false;
+        MediaFlyoutHeadsetControlsEnabled = false;
         NIconSymbol = false;
         NIconHide = false;
         DisableIfFullscreen = true;