FIX: ISXB-1221 input action binding discarded (#2119)

Author: smnwttbr

Packages/com.unity.inputsystem/CHANGELOG.md

@@ -24,6 +24,7 @@ however, it has to be formatted properly to pass verification tests.
 - Fixed an issue causing InvalidOperationException when entering playmode with domain reload disabled. [ISXB-1208](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-1208).
 - Fixed an issue where compiling Addressables with Input System package present would result in failed compilation due to `IInputAnalytic.TryGatherData` not being defined [ISXB-1203](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-1203).
 - Pinned Touch Samples sample package dependencies to avoid errors with Cinemachine 3.x and Probuilder 6.x. [ISXB-1245](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-1245)
+- Fixed issue where a binding path is sometimes not saved when chosen from the binding path picker. [ISXB-1221](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-1221)
 - Fixed an issue where dropdown menu for Path in Input Actions Editor could not be selected from any button position. [ISXB-1309](https://issuetracker.unity3d.com/product/unity/issues/guid/ISXB-1309)
 
 ## [1.12.0] - 2025-01-15

Packages/com.unity.inputsystem/InputSystem/Editor/ControlPicker/InputControlPathEditor.cs

@@ -30,15 +30,17 @@ public InputControlPathEditor(SerializedProperty pathProperty, InputControlPicke
         {
             if (pathProperty == null)
                 throw new ArgumentNullException(nameof(pathProperty));
-
-            this.pathProperty = pathProperty;
+            // Update the static pathProperty variable to the most recent serializedProperty.
+            // See comment on pathProperty for more information.
+            s_pathProperty = pathProperty;
             this.onModified = onModified;
             m_PickerState = pickerState ?? new InputControlPickerState();
             m_PathLabel = label ?? new GUIContent(pathProperty.displayName, pathProperty.GetTooltip());
         }
 
         public void Dispose()
         {
+            s_pathProperty = null;
             m_PickerDropdown?.Dispose();
         }
 
@@ -89,10 +91,10 @@ public void OnGUI()
             EditorGUILayout.EndHorizontal();
         }
 
+        //TODO: on next major version remove property argument.
         public void OnGUI(Rect rect, GUIContent label = null, SerializedProperty property = null, Action modifiedCallback = null)
         {
             var pathLabel = label ?? m_PathLabel;
-            var serializedProperty = property ?? pathProperty;
 
             var lineRect = rect;
             var labelRect = lineRect;
@@ -113,7 +115,7 @@ public void OnGUI(Rect rect, GUIContent label = null, SerializedProperty propert
             var path = String.Empty;
             try
             {
-                path = serializedProperty.stringValue;
+                path = pathProperty.stringValue;
             }
             catch
             {
@@ -138,8 +140,8 @@ public void OnGUI(Rect rect, GUIContent label = null, SerializedProperty propert
                 path = EditorGUI.DelayedTextField(bindingTextRect, path);
                 if (EditorGUI.EndChangeCheck())
                 {
-                    serializedProperty.stringValue = path;
-                    serializedProperty.serializedObject.ApplyModifiedProperties();
+                    pathProperty.stringValue = path;
+                    pathProperty.serializedObject.ApplyModifiedProperties();
                     (modifiedCallback ?? onModified).Invoke();
                 }
             }
@@ -148,9 +150,9 @@ public void OnGUI(Rect rect, GUIContent label = null, SerializedProperty propert
                 // Dropdown that shows binding text and allows opening control picker.
                 if (EditorGUI.DropdownButton(bindingTextRect, new GUIContent(displayName), FocusType.Keyboard))
                 {
-                    SetExpectedControlLayoutFromAttribute(serializedProperty);
+                    SetExpectedControlLayoutFromAttribute(pathProperty);
                     ////TODO: for bindings that are part of composites, use the layout information from the [InputControl] attribute on the field
-                    ShowDropdown(bindingTextRect, serializedProperty, modifiedCallback ?? onModified);
+                    ShowDropdown(bindingTextRect, modifiedCallback ?? onModified);
                 }
             }
 
@@ -159,7 +161,7 @@ public void OnGUI(Rect rect, GUIContent label = null, SerializedProperty propert
                 EditorStyles.miniButton);
         }
 
-        private void ShowDropdown(Rect rect, SerializedProperty serializedProperty, Action modifiedCallback)
+        private void ShowDropdown(Rect rect, Action modifiedCallback)
         {
             #if UNITY_INPUT_SYSTEM_PROJECT_WIDE_ACTIONS
             InputActionsEditorSettingsProvider.SetIMGUIDropdownVisible(true, false);
@@ -170,19 +172,13 @@ private void ShowDropdown(Rect rect, SerializedProperty serializedProperty, Acti
                     m_PickerState,
                     path =>
                     {
-                        serializedProperty.stringValue = path;
+                        pathProperty.stringValue = path;
+                        pathProperty.serializedObject.ApplyModifiedProperties();
                         m_PickerState.manualPathEditMode = false;
                         modifiedCallback();
                     });
             }
 
-            m_PickerDropdown.SetPickedCallback(path =>
-            {
-                serializedProperty.stringValue = path;
-                m_PickerState.manualPathEditMode = false;
-                modifiedCallback();
-            });
-
             m_PickerDropdown.SetControlPathsToMatch(m_ControlPathsToMatch);
             m_PickerDropdown.SetExpectedControlLayout(m_ExpectedControlLayout);
 
@@ -200,7 +196,16 @@ private void SetExpectedControlLayoutFromAttribute(SerializedProperty property)
                 SetExpectedControlLayout(attribute.layout);
         }
 
-        public SerializedProperty pathProperty { get; }
+        // This static variable is a hack. Because the editor is rebuilt at unpredictable times with a new serializedObject, we need to keep updating
+        // this variable with most up to date serializedProperty, so that the picker dropdown can access the correct serializedProperty.
+        // The picker dropdown is a separate window and does not have access to the changed serializedObject reference.
+        // This could be removed if the InputControlPathEditor is converted to UITK with a stable, persistent serializedObject backing this editor.
+        // This property will be shared among multiple asset editor windows.
+        private static SerializedProperty s_pathProperty { get; set; }
+
+        // This property will always return the most recent serializedProperty.
+        public SerializedProperty pathProperty { get => s_pathProperty;}
+
         public Action onModified { get; }
 
         private GUIContent m_PathLabel;

Packages/com.unity.inputsystem/InputSystem/Editor/ControlPicker/InputControlPickerDropdown.cs

@@ -58,11 +58,6 @@ public void SetExpectedControlLayout(string expectedControlLayout)
             Reload();
         }
 
-        public void SetPickedCallback(Action<string> action)
-        {
-            m_OnPickCallback = action;
-        }
-
         protected override void OnDestroy()
         {
             #if UNITY_INPUT_SYSTEM_PROJECT_WIDE_ACTIONS

Packages/com.unity.inputsystem/InputSystem/Editor/PropertyDrawers/InputControlPathDrawer.cs

@@ -44,7 +44,7 @@ public override void OnGUI(Rect position, SerializedProperty property, GUIConten
             }
 
             EditorGUI.BeginProperty(position, label, property);
-            m_Editor.OnGUI(position, label, property, () => property.serializedObject.ApplyModifiedProperties());
+            m_Editor.OnGUI(position, label, property: null, modifiedCallback: () => property.serializedObject.ApplyModifiedProperties());
             EditorGUI.EndProperty();
         }
     }