Remove externally exposed Expanded state and change behaviour and visuals surrounding it

osu.Game/Graphics/UserInterface/Nub.cs

@@ -17,11 +17,10 @@ using osu.Game.Overlays;
 
 namespace osu.Game.Graphics.UserInterface
 {
-    public class Nub : CircularContainer, IHasCurrentValue<bool>, IHasAccentColour
+    public class Nub : CompositeDrawable, IHasCurrentValue<bool>, IHasAccentColour
     {
         public const float HEIGHT = 15;
 
-        public const float COLLAPSED_SIZE = 30;
         public const float EXPANDED_SIZE = 50;
 
         private const float border_width = 3;
@@ -29,32 +28,34 @@ namespace osu.Game.Graphics.UserInterface
         private const double animate_in_duration = 200;
         private const double animate_out_duration = 500;
 
+        private readonly Box fill;
+        private readonly Container main;
+
         public Nub()
         {
-            Box fill;
+            Size = new Vector2(EXPANDED_SIZE, HEIGHT);
 
-            Size = new Vector2(COLLAPSED_SIZE, HEIGHT);
+            InternalChildren = new[]
-
-            BorderColour = Color4.White;
-            BorderThickness = border_width;
-
-            Masking = true;
-
-            Children = new[]
             {
-                fill = new Box
+                main = new CircularContainer
                 {
+                    BorderColour = Color4.White,
+                    BorderThickness = border_width,
+                    Masking = true,
                     RelativeSizeAxes = Axes.Both,
-                    Alpha = 0,
+                    Anchor = Anchor.TopCentre,
-                    AlwaysPresent = true,
+                    Origin = Anchor.TopCentre,
+                    Children = new Drawable[]
+                    {
+                        fill = new Box
+                        {
+                            RelativeSizeAxes = Axes.Both,
+                            Alpha = 0,
+                            AlwaysPresent = true,
+                        },
+                    }
                 },
             };
-
-            Current.ValueChanged += filled =>
-            {
-                fill.FadeTo(filled.NewValue ? 1 : 0, 200, Easing.OutQuint);
-                this.TransformTo(nameof(BorderThickness), filled.NewValue ? 8.5f : border_width, 200, Easing.OutQuint);
-            };
         }
 
         [BackgroundDependencyLoader(true)]
@@ -64,7 +65,7 @@ namespace osu.Game.Graphics.UserInterface
             GlowingAccentColour = colourProvider?.Highlight1.Lighten(0.2f) ?? colours.PinkLighter;
             GlowColour = colourProvider?.Light4 ?? colours.PinkDarker;
 
-            EdgeEffect = new EdgeEffectParameters
+            main.EdgeEffect = new EdgeEffectParameters
             {
                 Colour = GlowColour.Opacity(0),
                 Type = EdgeEffectType.Glow,
@@ -73,6 +74,13 @@ namespace osu.Game.Graphics.UserInterface
             };
         }
 
+        protected override void LoadComplete()
+        {
+            base.LoadComplete();
+
+            Current.BindValueChanged(onCurrentValueChanged, true);
+        }
+
         private bool glowing;
 
         public bool Glowing
@@ -84,28 +92,17 @@ namespace osu.Game.Graphics.UserInterface
 
                 if (value)
                 {
-                    this.FadeColour(GlowingAccentColour, animate_in_duration, Easing.OutQuint);
+                    main.FadeColour(GlowingAccentColour, animate_in_duration, Easing.OutQuint);
-                    FadeEdgeEffectTo(0.6f, animate_in_duration, Easing.OutQuint);
+                    main.FadeEdgeEffectTo(0.6f, animate_in_duration, Easing.OutQuint);
                 }
                 else
                 {
-                    FadeEdgeEffectTo(0, animate_out_duration);
+                    main.FadeEdgeEffectTo(0, animate_out_duration);
-                    this.FadeColour(AccentColour, animate_out_duration);
+                    main.FadeColour(AccentColour, animate_out_duration);
                 }
             }
         }
 
-        public bool Expanded
-        {
-            set
-            {
-                if (value)
-                    this.ResizeTo(new Vector2(EXPANDED_SIZE, HEIGHT), animate_in_duration, Easing.OutQuint);
-                else
-                    this.ResizeTo(new Vector2(COLLAPSED_SIZE, HEIGHT), animate_out_duration, Easing.OutQuint);
-            }
-        }
-
         private readonly Bindable<bool> current = new Bindable<bool>();
 
         public Bindable<bool> Current
@@ -130,7 +127,7 @@ namespace osu.Game.Graphics.UserInterface
             {
                 accentColour = value;
                 if (!Glowing)
-                    Colour = value;
+                    main.Colour = value;
             }
         }
 
@@ -143,7 +140,7 @@ namespace osu.Game.Graphics.UserInterface
             {
                 glowingAccentColour = value;
                 if (Glowing)
-                    Colour = value;
+                    main.Colour = value;
             }
         }
 
@@ -158,8 +155,20 @@ namespace osu.Game.Graphics.UserInterface
 
                 var effect = EdgeEffect;
                 effect.Colour = Glowing ? value : value.Opacity(0);
-                EdgeEffect = effect;
+                main.EdgeEffect = effect;
             }
         }
+
+        private void onCurrentValueChanged(ValueChangedEvent<bool> filled)
+        {
+            fill.FadeTo(filled.NewValue ? 1 : 0, 200, Easing.OutQuint);
+
+            if (filled.NewValue)
+                main.ResizeWidthTo(1, animate_in_duration, Easing.OutElasticHalf);
+            else
+                main.ResizeWidthTo(0.9f, animate_out_duration, Easing.OutElastic);
+
+            main.TransformTo(nameof(BorderThickness), filled.NewValue ? 8.5f : border_width, 200, Easing.OutQuint);
+        }
     }
 }

osu.Game/Graphics/UserInterface/OsuCheckbox.cs

@@ -9,16 +9,11 @@ using osu.Framework.Graphics.Sprites;
 using osu.Framework.Graphics.UserInterface;
 using osu.Framework.Input.Events;
 using osu.Game.Graphics.Containers;
-using osuTK.Graphics;
 
 namespace osu.Game.Graphics.UserInterface
 {
     public class OsuCheckbox : Checkbox
     {
-        public Color4 CheckedColor { get; set; } = Color4.Cyan;
-        public Color4 UncheckedColor { get; set; } = Color4.White;
-        public int FadeDuration { get; set; }
-
         /// <summary>
         /// Whether to play sounds when the state changes as a result of user interaction.
         /// </summary>
@@ -104,14 +99,12 @@ namespace osu.Game.Graphics.UserInterface
         protected override bool OnHover(HoverEvent e)
         {
             Nub.Glowing = true;
-            Nub.Expanded = true;
             return base.OnHover(e);
         }
 
         protected override void OnHoverLost(HoverLostEvent e)
         {
             Nub.Glowing = false;
-            Nub.Expanded = false;
             base.OnHoverLost(e);
         }
 

osu.Game/Graphics/UserInterface/OsuSliderBar.cs

@@ -120,7 +120,6 @@ namespace osu.Game.Graphics.UserInterface
                     {
                         Origin = Anchor.TopCentre,
                         RelativePositionAxes = Axes.X,
-                        Expanded = true,
                         Current = { Value = true }
                     },
                 },