Hook up a dropdown to show all available sprites for the current skin

osu.Game/Configuration/SettingSourceAttribute.cs

@@ -88,6 +88,7 @@ namespace osu.Game.Configuration
                         throw new InvalidOperationException($"{nameof(SettingSourceAttribute)} had an unsupported custom control type ({controlType.ReadableName()})");
 
                     var control = (Drawable)Activator.CreateInstance(controlType);
+                    controlType.GetProperty(nameof(SettingsItem<object>.Source))?.SetValue(control, obj);
                     controlType.GetProperty(nameof(SettingsItem<object>.LabelText))?.SetValue(control, attr.Label);
                     controlType.GetProperty(nameof(SettingsItem<object>.TooltipText))?.SetValue(control, attr.Description);
                     controlType.GetProperty(nameof(SettingsItem<object>.Current))?.SetValue(control, value);

osu.Game/Overlays/Settings/SettingsItem.cs

@@ -11,6 +11,7 @@ using osu.Framework.Graphics.Cursor;
 using osu.Framework.Graphics.Sprites;
 using osu.Framework.Graphics.UserInterface;
 using osu.Framework.Localisation;
+using osu.Game.Configuration;
 using osu.Game.Graphics;
 using osu.Game.Graphics.Sprites;
 using osu.Game.Graphics.Containers;
@@ -24,6 +25,11 @@ namespace osu.Game.Overlays.Settings
 
         protected Drawable Control { get; }
 
+        /// <summary>
+        /// The source component if this <see cref="SettingsItem{T}"/> was created via <see cref="SettingSourceAttribute"/>.
+        /// </summary>
+        public Drawable Source { get; internal set; }
+
         private IHasCurrentValue<T> controlWithCurrent => Control as IHasCurrentValue<T>;
 
         protected override Container<Drawable> Content => FlowContent;

osu.Game/Skinning/Components/SkinnableSprite.cs

@@ -1,6 +1,8 @@
 // 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.Collections.Generic;
+using System.Linq;
 using JetBrains.Annotations;
 using osu.Framework.Allocation;
 using osu.Framework.Bindables;
@@ -8,6 +10,7 @@ using osu.Framework.Graphics;
 using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Sprites;
 using osu.Game.Configuration;
+using osu.Game.Overlays.Settings;
 
 namespace osu.Game.Skinning.Components
 {
@@ -19,12 +22,14 @@ namespace osu.Game.Skinning.Components
     {
         public bool UsesFixedAnchor { get; set; }
 
-        [SettingSource("Sprite name", "The filename of the sprite")]
+        [SettingSource("Sprite name", "The filename of the sprite", SettingControlType = typeof(SpriteSelectorControl))]
         public Bindable<string> SpriteName { get; } = new Bindable<string>(string.Empty);
 
         [Resolved]
         private ISkinSource source { get; set; }
 
+        public IEnumerable<string> AvailableFiles => (source.AllSources.First() as Skin)?.SkinInfo.PerformRead(s => s.Files.Select(f => f.Filename));
+
         public SkinSprite()
         {
             AutoSizeAxes = Axes.Both;
@@ -45,5 +50,17 @@ namespace osu.Game.Skinning.Components
                 };
             }, true);
         }
+
+        public class SpriteSelectorControl : SettingsDropdown<string>
+        {
+            public SkinSprite Source { get; set; }
+
+            protected override void LoadComplete()
+            {
+                base.LoadComplete();
+
+                Items = Source.AvailableFiles;
+            }
+        }
     }
 }

osu.Game/Skinning/Editor/SkinEditor.cs

@@ -351,7 +351,7 @@ namespace osu.Game.Skinning.Editor
                 // place component
                 placeComponent(new SkinSprite
                 {
-                    SpriteName = { Value = Path.GetFileNameWithoutExtension(file.Name) }
+                    SpriteName = { Value = file.Name }
                 });
             });