CHANGE: Update asset InputSystem.inputsettings to use UI Toolkit framework

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -28,6 +28,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 - Removed 32-bit compilation check for HID on Windows players, which had no impact anymore. (ISX-2543)
 - Migrated sample scenes to use Universal Render Pipeline (URP) with Built-in Render Pipeline fallback shaders. The URP package is now required to run the samples. (ISX-2343)
 - Changed the UI for `Actions.inputactions` asset to use UI Toolkit framework.
+- Changed the UI for `InputSystem.inputsettings` asset to use UI Toolkit framework.
 
 ### Added
 

Packages/com.unity.inputsystem/InputSystem/Editor/InputAssetEditorUtils.cs

@@ -3,6 +3,7 @@
 using System;
 using System.IO;
 using UnityEditor;
+using UnityEngine.UIElements;
 
 namespace UnityEngine.InputSystem.Editor
 {
@@ -19,7 +20,7 @@
             InvalidPath,
 
             /// <summary>
-            /// The dialog was cancelled by the user and the path is invalid.
+            /// The dialog was canceled by the user and the path is invalid.
             /// </summary>
             Cancelled,
 
@@ -82,12 +83,32 @@
             return asset;
         }
 
-        public static void DrawMakeActiveGui<T>(T current, T target, string targetName, string entity, Action<T> apply, bool allowAssignActive = true)
+        public static VisualElement CreateMakeActiveGui<T>(Func<T> getCurrent, T target, string targetName, string entity,
+            Action<T> apply, Action<Action> subscribeToChanges, Action<Action> unsubscribeFromChanges,
+            bool allowAssignActive = true)
             where T : ScriptableObject
         {
+            var container = new VisualElement();
+
+            void Refresh() => PopulateMakeActiveGui(container, getCurrent(), target, entity, apply, allowAssignActive);
+
+            Refresh();
+
+            // Subscribe for as long as the element is part of a panel, matching the pattern used in InputParameterEditor.
+            container.RegisterCallback<AttachToPanelEvent>(_ => subscribeToChanges(Refresh));
+            container.RegisterCallback<DetachFromPanelEvent>(_ => unsubscribeFromChanges(Refresh));
+
+            return container;
+        }
+
+        private static void PopulateMakeActiveGui<T>(VisualElement container, T current, T target, string entity, Action<T> apply, bool allowAssignActive)
+            where T : ScriptableObject
+        {
+            container.Clear();
+
             if (current == target)
             {
-                EditorGUILayout.HelpBox($"These actions are assigned as the {entity}.", MessageType.Info);
+                container.Add(new HelpBox($"These actions are assigned as the {entity}.", HelpBoxMessageType.Info));
                 return;
             }
 
@@ -96,11 +117,21 @@
                 currentlyActiveAssetsPath = AssetDatabase.GetAssetPath(current);
             if (!string.IsNullOrEmpty(currentlyActiveAssetsPath))
                 currentlyActiveAssetsPath = $" The actions currently assigned as the {entity} are: {currentlyActiveAssetsPath}. ";
-            EditorGUILayout.HelpBox($"These actions are not assigned as the {entity} for the Input System. {currentlyActiveAssetsPath??""}", MessageType.Warning);
-            GUI.enabled = allowAssignActive;
-            if (GUILayout.Button($"Assign as the {entity}", EditorStyles.miniButton))
+
+            container.Add(new HelpBox(
+                $"These actions are not assigned as the {entity} for the Input System. {currentlyActiveAssetsPath ?? ""}",
+                HelpBoxMessageType.Warning));
+
+            var assignButton = new Button(() =>
+            {
                 apply(target);
-            GUI.enabled = true;
+                PopulateMakeActiveGui(container, target, target, entity, apply, allowAssignActive);
+            })
+            {
+                text = $"Assign as the {entity}"
+            };
+            assignButton.SetEnabled(allowAssignActive);
+            container.Add(assignButton);
         }
 
         public static bool IsValidFileExtension(string path)

Packages/com.unity.inputsystem/InputSystem/Editor/Settings/InputSettingsProvider.cs

@@ -489,17 +489,36 @@
     [CustomEditor(typeof(InputSettings))]
     internal class InputSettingsEditor : UnityEditor.Editor
     {
-        public override void OnInspectorGUI()
+        public override VisualElement CreateInspectorGUI()
         {
-            EditorGUILayout.Space();
+            var root = new VisualElement();
 
-            if (GUILayout.Button("Open Input Settings Window", GUILayout.Height(30)))
-                InputSettingsProvider.Open();
-
-            EditorGUILayout.Space();
+            var openButton = new Button(() => InputSettingsProvider.Open())
+            {
+                text = "Open Input Settings Window",
+                style = { minHeight = 30, whiteSpace = WhiteSpace.Normal }
+            };
+            root.Add(openButton);
+
+            // UndoRedoCallback is void(), not Action, so an adapter is required.
+            // The variable is shared between the two lambdas so the same instance is removed on unsubscribe.
+            Undo.UndoRedoCallback undoRedoAdapter = null;
+            root.Add(InputAssetEditorUtils.CreateMakeActiveGui(
+                () => InputSystem.settings, target as InputSettings,
+                target.name, "settings", (value) => InputSystem.settings = value,
+                handler =>
+                {
+                    InputSystem.onSettingsChange += handler;
+                    undoRedoAdapter = () => handler();
+                    Undo.undoRedoPerformed += undoRedoAdapter;
+                },
+                handler =>
+                {
+                    InputSystem.onSettingsChange -= handler;
+                    Undo.undoRedoPerformed -= undoRedoAdapter;
+                }));
 
-            InputAssetEditorUtils.DrawMakeActiveGui(InputSystem.settings, target as InputSettings,
-                target.name, "settings", (value) => InputSystem.settings = value);
+            return root;
         }
 
         protected override bool ShouldHideOpenButton()