diff --git a/Src/Core/Optional/Optional.cs b/Src/Core/Optional/Optional.cs
index b9f27cd..f0f24b3 100644
--- a/Src/Core/Optional/Optional.cs
+++ b/Src/Core/Optional/Optional.cs
@@ -1,4 +1,5 @@
 using System;
+using Cysharp.Threading.Tasks;
 
 namespace BITKit
 {
@@ -70,6 +71,22 @@ namespace BITKit
             return Allow ? Value : other.Invoke();
         }
 
+        public async UniTask<T> IfNotAllowAsync(Func<UniTask<T>> func)
+        {
+            return Allow ? Value : await func.Invoke();
+        }
+
+        public async UniTask<T> SetValueThenAllowAsync(Func<UniTask<T>> func)
+        {
+            if (Allow)
+            {
+                return value;
+            }
+            value = await func.Invoke();
+            allow = true;
+            return value;
+        }
+
         public void SetValueThenAllow(T newValue)
         {
             value = newValue;
diff --git a/Src/Core/Wrapper/IWrapper.cs b/Src/Core/Wrapper/IWrapper.cs
index 7c38bfe..abab98c 100644
--- a/Src/Core/Wrapper/IWrapper.cs
+++ b/Src/Core/Wrapper/IWrapper.cs
@@ -9,19 +9,37 @@ namespace BITKit
     }
     public interface IWrapper<T>:IWrapper
     {
+        public  Action<T, T> OnValueChanged  { get; set; }
         public T Value { get; set; }
     }
     public class ValueWrapper<T> : IWrapper<T>
     {
-        public T Value { get; set; }=default;
-        public object Obj { get => Value; set => Value = (T)value; }
+        public Action<T, T> OnValueChanged { get; set; }
+
+        public T Value
+        {
+            get => _value;
+            set
+            {
+                var prev = _value;
+                _value = value;
+                OnValueChanged?.Invoke(prev,value);
+            }
+        }
+
+        private T _value = typeof(T) == typeof(string) ? string.Empty.As<T>() : Activator.CreateInstance<T>();
+        public object Obj
+        {
+            get => Value;
+            set => Value = (T)value;
+        }
     }
 
     public class PropertyWrapper<T> : IWrapper<T>
     {
         private readonly PropertyInfo _field;
         private readonly object _target;
-        public event Action<T, T> OnValueChanged; 
+        public Action<T, T> OnValueChanged  { get; set; }
         public PropertyWrapper(PropertyInfo field, object target)
         {
             _field = field;
@@ -40,8 +58,8 @@ namespace BITKit
 
         public object Obj
         {
-            get => _field.GetValue(_target);
-            set => _field.SetValue(_target, value);
+            get => Value;
+            set => Value = (T)value;
         }
     }
     public class FieldWrapper<T> : IWrapper<T>
@@ -53,16 +71,23 @@ namespace BITKit
             _field = field;
             _target = target ?? throw new ArgumentNullException(nameof(target));
         }
+
+        public Action<T, T> OnValueChanged  { get; set; }
+
         public T Value
         {
             get => (T)_field.GetValue(_target);
-            set => _field.SetValue(_target, value);
+            set
+            {
+                OnValueChanged?.Invoke(Value, value);
+                _field.SetValue(_target, value);
+            }
         }
 
         public object Obj
         {
-            get => _field.GetValue(_target);
-            set => _field.SetValue(_target, value);
+            get => Value;
+            set => Value = (T)value;
         }
     }
     public class FuncWrapper<T> : IWrapper<T>
@@ -74,6 +99,9 @@ namespace BITKit
             _get = get;
             _set = set;
         }
+
+        public Action<T, T> OnValueChanged  { get; set; }
+
         public T Value
         {
             get => _get();
@@ -82,8 +110,8 @@ namespace BITKit
 
         public object Obj
         {
-            get => _get();
-            set => _set((T)value);
+            get => Value;
+            set => Value = (T)value;
         }
     }
 }