Restore values from json on create new managed reference

Author: mackysoft

Assets/MackySoft/MackySoft.SerializeReferenceExtensions/Editor/ManagedReferenceUtility.cs

@@ -2,14 +2,27 @@
 using System;
 using System.Reflection;
 using UnityEditor;
+using UnityEngine;
 
 namespace MackySoft.SerializeReferenceExtensions.Editor {
 	public static class ManagedReferenceUtility {
 
 		public static object SetManagedReference (this SerializedProperty property,Type type) {
-			object obj = (type != null) ? Activator.CreateInstance(type) : null;
-			property.managedReferenceValue = obj;
-			return obj;
+			object result;
+			if (property.managedReferenceValue != null)
+			{
+				// Restore an previous values from json.
+				string json = JsonUtility.ToJson(property.managedReferenceValue);
+				result = JsonUtility.FromJson(json, type);
+			}
+			else
+			{
+				result = (type != null) ? Activator.CreateInstance(type) : null;
+			}
+			
+			property.managedReferenceValue = result;
+			return result;
+
 		}
 
 		public static Type GetType (string typeName) {