Use ExpandingButtonContainer in editor composer

osu.Game/Overlays/SettingsToolboxGroup.cs

@@ -94,9 +94,11 @@ namespace osu.Game.Overlays
                                 {
                                     Origin = Anchor.CentreLeft,
                                     Anchor = Anchor.CentreLeft,
+                                    RelativeSizeAxes = Axes.X,
+                                    Truncate = true,
                                     Text = title.ToUpperInvariant(),
                                     Font = OsuFont.GetFont(weight: FontWeight.Bold, size: 17),
-                                    Margin = new MarginPadding { Left = 10 },
+                                    Padding = new MarginPadding { Left = 10, Right = 30 },
                                 },
                                 button = new IconButton
                                 {

osu.Game/Rulesets/Edit/EditorToolboxGroup.cs

@@ -2,13 +2,13 @@
 // See the LICENCE file in the repository root for full licence text.
 
 using osu.Framework.Graphics;
-using osu.Game.Screens.Play.PlayerSettings;
+using osu.Game.Overlays;
 
 namespace osu.Game.Rulesets.Edit
 {
-    public class ToolboxGroup : PlayerSettingsGroup
+    public class EditorToolboxGroup : SettingsToolboxGroup
     {
-        public ToolboxGroup(string title)
+        public EditorToolboxGroup(string title)
             : base(title)
         {
             RelativeSizeAxes = Axes.X;

osu.Game/Rulesets/Edit/HitObjectComposer.cs

@@ -13,6 +13,7 @@ using osu.Framework.Input;
 using osu.Framework.Input.Events;
 using osu.Framework.Logging;
 using osu.Game.Beatmaps;
+using osu.Game.Overlays;
 using osu.Game.Rulesets.Configuration;
 using osu.Game.Rulesets.Edit.Tools;
 using osu.Game.Rulesets.Mods;
@@ -98,8 +99,6 @@ namespace osu.Game.Rulesets.Edit
 
             dependencies.CacheAs(Playfield);
 
-            const float toolbar_width = 200;
-
             InternalChildren = new Drawable[]
             {
                 new Container
@@ -116,20 +115,15 @@ namespace osu.Game.Rulesets.Edit
                                               .WithChild(BlueprintContainer = CreateBlueprintContainer())
                     }
                 },
-                new FillFlowContainer
+                new LeftToolboxFlow
                 {
-                    Name = "Sidebar",
-                    RelativeSizeAxes = Axes.Y,
-                    Width = toolbar_width,
-                    Padding = new MarginPadding { Right = 10 },
-                    Spacing = new Vector2(10),
                     Children = new Drawable[]
                     {
-                        new ToolboxGroup("toolbox (1-9)")
+                        new EditorToolboxGroup("toolbox (1-9)")
                         {
                             Child = toolboxCollection = new EditorRadioButtonCollection { RelativeSizeAxes = Axes.X }
                         },
-                        new ToolboxGroup("toggles (Q~P)")
+                        new EditorToolboxGroup("toggles (Q~P)")
                         {
                             Child = togglesCollection = new FillFlowContainer
                             {
@@ -426,6 +420,18 @@ namespace osu.Game.Rulesets.Edit
         }
 
         #endregion
+
+        private class LeftToolboxFlow : ExpandingButtonContainer
+        {
+            public LeftToolboxFlow()
+                : base(80, 200)
+            {
+                RelativeSizeAxes = Axes.Y;
+                Padding = new MarginPadding { Right = 10 };
+
+                FillFlow.Spacing = new Vector2(10);
+            }
+        }
     }
 
     /// <summary>

osu.Game/Rulesets/Edit/ScrollingToolboxGroup.cs

@@ -7,7 +7,7 @@ using osu.Game.Graphics.Containers;
 
 namespace osu.Game.Rulesets.Edit
 {
-    public class ScrollingToolboxGroup : ToolboxGroup
+    public class ScrollingToolboxGroup : EditorToolboxGroup
     {
         protected readonly OsuScrollContainer Scroll;