Refactor SkinEditor to support switching target screens without full reload

osu.Game/OsuGame.cs

@@ -1142,8 +1142,6 @@ namespace osu.Game
 
         private void screenChanged(IScreen current, IScreen newScreen)
         {
-            skinEditor.Reset();
-
             switch (newScreen)
             {
                 case IntroScreen intro:
@@ -1185,6 +1183,8 @@ namespace osu.Game
                 else
                     BackButton.Hide();
             }
+
+            skinEditor.SetTarget((Screen)newScreen);
         }
 
         private void screenPushed(IScreen lastScreen, IScreen newScreen) => screenChanged(lastScreen, newScreen);

osu.Game/Skinning/Editor/SkinEditor.cs

@@ -28,7 +28,7 @@ namespace osu.Game.Skinning.Editor
 
         protected override bool StartHidden => true;
 
-        private readonly Drawable targetScreen;
+        private Drawable targetScreen;
 
         private OsuTextFlowContainer headerText;
 
@@ -42,11 +42,13 @@ namespace osu.Game.Skinning.Editor
 
         private bool hasBegunMutating;
 
+        private Container blueprintContainerContainer;
+
         public SkinEditor(Drawable targetScreen)
         {
-            this.targetScreen = targetScreen;
-
             RelativeSizeAxes = Axes.Both;
+
+            UpdateTargetScreen(targetScreen);
         }
 
         [BackgroundDependencyLoader]
@@ -113,13 +115,9 @@ namespace osu.Game.Skinning.Editor
                                     Origin = Anchor.CentreLeft,
                                     RequestPlacement = placeComponent
                                 },
-                                new Container
+                                blueprintContainerContainer = new Container
                                 {
                                     RelativeSizeAxes = Axes.Both,
-                                    Children = new Drawable[]
-                                    {
-                                        new SkinBlueprintContainer(targetScreen),
-                                    }
                                 },
                             }
                         }
@@ -147,6 +145,21 @@ namespace osu.Game.Skinning.Editor
             }, true);
         }
 
+        public void UpdateTargetScreen(Drawable targetScreen)
+        {
+            this.targetScreen = targetScreen;
+
+            Scheduler.AddOnce(loadBlueprintContainer);
+
+            void loadBlueprintContainer()
+            {
+                blueprintContainerContainer.Children = new Drawable[]
+                {
+                    new SkinBlueprintContainer(targetScreen),
+                };
+            }
+        }
+
         private void skinChanged()
         {
             headerText.Clear();

osu.Game/Skinning/Editor/SkinEditorOverlay.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.Diagnostics;
 using JetBrains.Annotations;
 using osu.Framework.Bindables;
 using osu.Framework.Graphics;
@@ -8,6 +9,7 @@ using osu.Framework.Graphics.Containers;
 using osu.Framework.Graphics.Primitives;
 using osu.Framework.Input.Bindings;
 using osu.Framework.Input.Events;
+using osu.Framework.Screens;
 using osu.Game.Graphics.Containers;
 using osu.Game.Input.Bindings;
 
@@ -114,15 +116,36 @@ namespace osu.Game.Skinning.Editor
         }
 
         /// <summary>
-        /// Exit any existing skin editor due to the game state changing.
+        /// Set a new target screen which will be used to find skinnable components.
         /// </summary>
-        public void Reset()
+        public void SetTarget(Screen screen)
         {
-            skinEditor?.Save();
+            if (skinEditor == null) return;
-            skinEditor?.Hide();
-            skinEditor?.Expire();
 
-            skinEditor = null;
+            skinEditor.Save();
+
+            // AddOnce with paramter will ensure the newest target is loaded if there is any overlap.
+            Scheduler.AddOnce(setTarget, screen);
+        }
+
+        private void setTarget(Screen target)
+        {
+            Debug.Assert(skinEditor != null);
+
+            if (!target.IsLoaded)
+            {
+                Scheduler.AddOnce(setTarget, target);
+                return;
+            }
+
+            if (skinEditor.State.Value == Visibility.Visible)
+                skinEditor.UpdateTargetScreen(target);
+            else
+            {
+                skinEditor.Hide();
+                skinEditor.Expire();
+                skinEditor = null;
+            }
         }
     }
 }