FIX: Action Maps contextual menu in Action Editor UI that could display unrelated items. (#2008)

* Fixed Action Maps contextual menu in Action Editor UI that could display unrelated items.

* reworked to reduce allocation

Author: bmalrat

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -13,6 +13,7 @@ however, it has to be formatted properly to pass verification tests.
 ### Fixed
 - Fixed Multiple interactions could breaks on Composite Binding. [ISXB-619](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-619)
 - Fixed memory leak when the OnScreenStick component was destroyed [ISXB-1070](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-1070). Contribution by [LukeUnityDev](https://github.com/LukeUnityDev).
+- Fixed Action Maps contextual menu in Action Editor UI that occasionally displays unrelated items.
 
 ### Changed
 - Renamed editor Resources directories to PackageResources to fix package validation warnings.

Packages/com.unity.inputsystem/InputSystem/Editor/UITKAssetEditor/Views/ContextMenu.cs

@@ -27,7 +27,7 @@ internal static class ContextMenu
         #region ActionMaps
         public static void GetContextMenuForActionMapItem(ActionMapsView mapView, InputActionMapsTreeViewItem treeViewItem, int index)
         {
-            _ = new ContextualMenuManipulator(menuEvent =>
+            treeViewItem.OnContextualMenuPopulateEvent = (menuEvent =>
             {
                 // TODO: AddAction should enable m_RenameOnActionAdded
                 menuEvent.menu.AppendAction(add_Action_String, _ => mapView.Dispatch(Commands.AddAction()));
@@ -42,7 +42,7 @@ public static void GetContextMenuForActionMapItem(ActionMapsView mapView, InputA
                 var copiedAction = CopyPasteHelper.GetCopiedClipboardType() == typeof(InputAction);
                 if (CopyPasteHelper.HasPastableClipboardData(typeof(InputActionMap)))
                     menuEvent.menu.AppendAction(paste_String, _ => mapView.PasteItems(copiedAction));
-            }) { target = treeViewItem };
+            });
         }
 
         // Add "Add Action Map" option to empty space under the ListView. Matches with old IMGUI style (ISX-1519).

Packages/com.unity.inputsystem/InputSystem/Editor/UITKAssetEditor/Views/InputActionMapsTreeViewItem.cs

@@ -1,6 +1,7 @@
 // UITK TreeView is not supported in earlier versions
 // Therefore the UITK version of the InputActionAsset Editor is not available on earlier Editor versions either.
 #if UNITY_EDITOR && UNITY_INPUT_SYSTEM_PROJECT_WIDE_ACTIONS
+using System;
 using System.Threading.Tasks;
 using UnityEditor;
 using UnityEngine.InputSystem.Editor;
@@ -17,6 +18,7 @@ internal class InputActionMapsTreeViewItem : VisualElement
 
         private const string kRenameTextField = "rename-text-field";
         public event EventCallback<string> EditTextFinished;
+        public Action<ContextualMenuPopulateEvent> OnContextualMenuPopulateEvent;
 
         // for testing purposes to know if the item is focused to accept input
         internal bool IsFocused { get; private set; } = false;
@@ -41,6 +43,11 @@ public InputActionMapsTreeViewItem()
             RegisterCallback<MouseDownEvent>(OnMouseDownEventForRename);
             renameTextfield.RegisterCallback<FocusInEvent>(e => IsFocused = true);
             renameTextfield.RegisterCallback<FocusOutEvent>(e => { OnEditTextFinished(); IsFocused = false; });
+            _ = new ContextualMenuManipulator(menuBuilder =>
+            {
+                OnContextualMenuPopulateEvent?.Invoke(menuBuilder);
+            })
+            { target = this };
         }
 
         public Label label => this.Q<Label>();