Receive callbacks when a bound property changes

Example overview

GameObject

Prerequisites

• TrackPropertyValue()

• Unbind()

Create the binding to receive a callback

• Calls the

  CheckName()

  method whenever the value of a serialized property changes
• Registers the method with the

  TrackPropertyValue()

  extension method
• Calls

  Unbind()

  before calling the

  TrackPropertyValue()

  again on another property.

VisualElement

1. Create a project in Unity with any template.
2. In your Project window, create a folder named

   callback-SerializedProperty-changes

   to store your files.
3. In the callback-SerializedProperty-change folder, create a folder named

   Editor

   .
4. In the Editor folder, create a C# script named

   SimpleBindingPropertyTrackingExample.cs

   and replace its contents with the following:

   using UnityEditor;using UnityEngine;using UnityEditor.UIElements;using UnityEngine.UIElements;namespace UIToolkitExamples{    public class SimpleBindingPropertyTrackingExample : EditorWindow    {        TextField m_ObjectNameBinding;        [MenuItem("Window/UIToolkitExamples/Simple Binding Property Tracking Example")]        public static void ShowDefaultWindow()        {            var wnd = GetWindow<SimpleBindingPropertyTrackingExample>();            wnd.titleContent = new GUIContent("Simple Binding Property Tracking");        }                public void CreateGUI()        {            m_ObjectNameBinding = new TextField("Object Name Binding");            rootVisualElement.Add(m_ObjectNameBinding);            OnSelectionChange();        }        public void OnSelectionChange()        {            GameObject selectedObject = Selection.activeObject as GameObject;            if (selectedObject != null)            {                // Create the SerializedObject from the current selection                SerializedObject so = new SerializedObject(selectedObject);                // Note: the "name" property of a GameObject is actually named "m_Name" in serialization.                SerializedProperty property = so.FindProperty("m_Name");                                // Ensure to use Unbind() before tracking a new property                m_ObjectNameBinding.Unbind();                m_ObjectNameBinding.TrackPropertyValue(property, CheckName);                // Bind the property to the field directly                m_ObjectNameBinding.BindProperty(property);                CheckName(property);            }            else            {                // Unbind any binding from the field                m_ObjectNameBinding.Unbind();            }        }        void CheckName(SerializedProperty property)        {            if (property.stringValue == "GameObject")            {                m_ObjectNameBinding.style.backgroundColor = Color.red * 0.5f;            }            else            {                m_ObjectNameBinding.style.backgroundColor = StyleKeyword.Null;            }        }    }}

Test the binding

1. In Unity, select Window > UIToolkitExamples > Simple Binding Property Tracking Example. A custom Editor window appears with a text field.
2. Select any GameObject in your scene. The name of the GameObject appears in your Editor window's text field.
3. Change the name of the GameObject in the text field. If the name is

   GameObject

   , the background color of the label changes to dark red.

Additional resources

• SerializedObject data binding
• Bindable elements
• Binding data type conversion
• Implementation details
• Binding examples