Use WeakEventManager to resolve memory leak

Author: Dwscdv3

EarTrumpet/AppSettings.cs

@@ -10,7 +10,7 @@ namespace EarTrumpet;
 public class AppSettings
 {
     public event EventHandler<bool> UseLegacyIconChanged;
-    public event EventHandler<bool> UseLogarithmicVolumeChanged;
+    public event EventHandler<EventArgs> UseLogarithmicVolumeChanged;
     public event Action FlyoutHotkeyTyped;
     public event Action MixerHotkeyTyped;
     public event Action SettingsHotkeyTyped;
@@ -164,7 +164,7 @@ public bool UseLogarithmicVolume
         set
         {
             _settings.Set("UseLogarithmicVolume", value);
-            UseLogarithmicVolumeChanged?.Invoke(this, value);
+            UseLogarithmicVolumeChanged?.Invoke(this, new EventArgs());
         }
     }
 
@@ -174,7 +174,7 @@ public float LogarithmicVolumeMinDb
         set
         {
             _settings.Set("LogarithmicVolumeMinDb", value);
-            UseLogarithmicVolumeChanged?.Invoke(this, UseLogarithmicVolume);
+            UseLogarithmicVolumeChanged?.Invoke(this, new EventArgs());
         }
     }
 

EarTrumpet/DataModel/WindowsAudio/Internal/AudioDeviceSession.cs

@@ -10,6 +10,7 @@
 using System.Runtime.InteropServices;
 using System.Text;
 using System.Threading.Tasks;
+using System.Windows;
 using System.Windows.Threading;
 using Windows.Win32;
 using Windows.Win32.Media.Audio;
@@ -193,8 +194,15 @@ public AudioDeviceSession(IAudioDevice parent, IAudioSessionControl session, Dis
             }
         }
 
-        // Potential memory leak: this class is not IDisposable, so we cannot unregister the event.
-        App.Settings.UseLogarithmicVolumeChanged += (sender, args) => RaisePropertyChanged(nameof(Volume));
+        WeakEventManager<AppSettings, EventArgs>.AddHandler(
+            App.Settings,
+            nameof(AppSettings.UseLogarithmicVolumeChanged),
+            UseLogarithmicVolumeChangedHandler);
+    }
+
+    private void UseLogarithmicVolumeChangedHandler(object sender, EventArgs e)
+    {
+        RaisePropertyChanged(nameof(Volume));
     }
 
     ~AudioDeviceSession()

EarTrumpet/UI/Controls/VolumeSlider.cs

@@ -41,11 +41,11 @@ public VolumeSlider() : base()
         Loaded += OnLoaded;
         Unloaded += OnUnloaded;
 
-        UseLogarithmicVolumeChangedHandler(null, App.Settings.UseLogarithmicVolume);
+        UseLogarithmicVolumeChangedHandler(null, new EventArgs());
         App.Settings.UseLogarithmicVolumeChanged += UseLogarithmicVolumeChangedHandler;
     }
 
-    private void UseLogarithmicVolumeChangedHandler(object sender, bool value)
+    private void UseLogarithmicVolumeChangedHandler(object sender, EventArgs e)
     {
         UpdateVolumeRange();
         SizeOrVolumeOrPeakValueChanged();