Code Quality: Unsubscribe events in MediaPreview (#17335)

Author: hishitetsu

src/Files.App/UserControls/FilePreviews/MediaPreview.xaml.cs

@@ -17,6 +17,7 @@ public MediaPreview(MediaPreviewViewModel model)
 			ViewModel = model;
 			InitializeComponent();
 			PlayerContext.Loaded += PlayerContext_Loaded;
+			PlayerContext.Unloaded += PlayerContext_Unloaded;
 			Unloaded += MediaPreview_Unloaded;
 		}
 
@@ -29,13 +30,20 @@ private void PlayerContext_Loaded(object sender, RoutedEventArgs e)
 			ViewModel.TogglePlaybackRequested += TogglePlaybackRequestInvoked;
 		}
 
+		private void PlayerContext_Unloaded(object sender, RoutedEventArgs e)
+		{
+			PlayerContext.MediaPlayer.VolumeChanged -= MediaPlayer_VolumeChanged;
+			ViewModel.TogglePlaybackRequested -= TogglePlaybackRequestInvoked;
+		}
+
 		private void MediaPreview_Unloaded(object sender, RoutedEventArgs e)
 		{
 			// The MediaPlayerElement isn't properly disposed by Windows so we set the source to null
 			// to avoid issues the next time the control is used.
 			PlayerContext.Source = null;
 
 			PlayerContext.Loaded -= PlayerContext_Loaded;
+			PlayerContext.Unloaded -= PlayerContext_Unloaded;
 			Unloaded -= MediaPreview_Unloaded;
 		}
 
@@ -47,7 +55,7 @@ private void MediaPlayer_VolumeChanged(MediaPlayer sender, object args)
 			}
 		}
 
-		private void TogglePlaybackRequestInvoked(object sender, EventArgs e)
+		private void TogglePlaybackRequestInvoked(object? sender, EventArgs e)
 		{
 			if (PlayerContext.MediaPlayer.PlaybackSession.PlaybackState is not MediaPlaybackState.Playing)
 			{