Add helper class for tracking changes to mod settings

osu.Game/Configuration/SettingSourceAttribute.cs

@@ -9,6 +9,7 @@ using JetBrains.Annotations;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
 using osu.Game.Overlays.Settings;
+using osu.Game.Rulesets.Mods;
 
 namespace osu.Game.Configuration
 {
@@ -140,4 +141,30 @@ namespace osu.Game.Configuration
             return orderedRelative.Concat(unordered);
         }
     }
+
+    public class ModSettingChangeTracker : IDisposable
+    {
+        public Action<Mod> SettingChanged;
+
+        private readonly List<ISettingsItem> references = new List<ISettingsItem>();
+
+        public ModSettingChangeTracker(IEnumerable<Mod> mods)
+        {
+            foreach (var mod in mods)
+            {
+                foreach (var setting in mod.CreateSettingsControls().OfType<ISettingsItem>())
+                {
+                    setting.SettingChanged += () => SettingChanged?.Invoke(mod);
+                    references.Add(setting);
+                }
+            }
+        }
+
+        public void Dispose()
+        {
+            foreach (var r in references)
+                r.Dispose();
+            references.Clear();
+        }
+    }
 }

osu.Game/Screens/Select/Details/AdvancedStats.cs

@@ -18,7 +18,6 @@ using System.Threading;
 using osu.Framework.Threading;
 using osu.Framework.Utils;
 using osu.Game.Configuration;
-using osu.Game.Overlays.Settings;
 using osu.Game.Rulesets;
 
 namespace osu.Game.Screens.Select.Details
@@ -83,32 +82,22 @@ namespace osu.Game.Screens.Select.Details
             mods.BindValueChanged(modsChanged, true);
         }
 
-        private readonly List<ISettingsItem> references = new List<ISettingsItem>();
+        private ModSettingChangeTracker settingChangeTracker;
+        private ScheduledDelegate debouncedStatisticsUpdate;
 
         private void modsChanged(ValueChangedEvent<IReadOnlyList<Mod>> mods)
         {
-            // TODO: find a more permanent solution for this if/when it is needed in other components.
+            settingChangeTracker?.Dispose();
-            // this is generating drawables for the only purpose of storing bindable references.
-            foreach (var r in references)
-                r.Dispose();
 
-            references.Clear();
+            settingChangeTracker = new ModSettingChangeTracker(mods.NewValue);
-
+            settingChangeTracker.SettingChanged += m =>
-            ScheduledDelegate debounce = null;
-
-            foreach (var mod in mods.NewValue.OfType<IApplicableToDifficulty>())
             {
-                foreach (var setting in mod.CreateSettingsControls().OfType<ISettingsItem>())
+                if (!(m is IApplicableToDifficulty))
-                {
+                    return;
-                    setting.SettingChanged += () =>
-                    {
-                        debounce?.Cancel();
-                        debounce = Scheduler.AddDelayed(updateStatistics, 100);
-                    };
 
-                    references.Add(setting);
+                debouncedStatisticsUpdate?.Cancel();
-                }
+                debouncedStatisticsUpdate = Scheduler.AddDelayed(updateStatistics, 100);
-            }
+            };
 
             updateStatistics();
         }