From 84637b59ef836b88f61842e4543920f3729d02be Mon Sep 17 00:00:00 2001
From: Salman Ahmed <frenzibyte@gmail.com>
Date: Wed, 25 Aug 2021 07:40:41 +0300
Subject: [PATCH] Define `DifficultyBindableWithCurrent` and use in
 `SliderControl`

---
 .../Mods/DifficultyAdjustSettingsControl.cs   | 28 ++++++++++++++++++-
 1 file changed, 27 insertions(+), 1 deletion(-)

diff --git a/osu.Game/Rulesets/Mods/DifficultyAdjustSettingsControl.cs b/osu.Game/Rulesets/Mods/DifficultyAdjustSettingsControl.cs
index 3978378c3a..67b24d24d0 100644
--- a/osu.Game/Rulesets/Mods/DifficultyAdjustSettingsControl.cs
+++ b/osu.Game/Rulesets/Mods/DifficultyAdjustSettingsControl.cs
@@ -1,6 +1,7 @@
 // Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
 // See the LICENCE file in the repository root for full licence text.
 
+using System;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
@@ -91,7 +92,7 @@ namespace osu.Game.Rulesets.Mods
         {
             // This is required as SettingsItem relies heavily on this bindable for internal use.
             // The actual update flow is done via the bindable provided in the constructor.
-            private readonly BindableWithCurrent<float?> current = new BindableWithCurrent<float?>();
+            private readonly DifficultyBindableWithCurrent current = new DifficultyBindableWithCurrent();
 
             public Bindable<float?> Current
             {
@@ -114,5 +115,30 @@ namespace osu.Game.Rulesets.Mods
                 RelativeSizeAxes = Axes.X;
             }
         }
+
+        private class DifficultyBindableWithCurrent : DifficultyBindable, IHasCurrentValue<float?>
+        {
+            private Bindable<float?> currentBound;
+
+            public Bindable<float?> Current
+            {
+                get => this;
+                set
+                {
+                    if (value == null)
+                        throw new ArgumentNullException(nameof(value));
+
+                    if (currentBound != null) UnbindFrom(currentBound);
+                    BindTo(currentBound = value);
+                }
+            }
+
+            public DifficultyBindableWithCurrent(float? defaultValue = default)
+                : base(defaultValue)
+            {
+            }
+
+            protected override Bindable<float?> CreateInstance() => new DifficultyBindableWithCurrent();
+        }
     }
 }