/// <summary>
 /// Creates a new instance of the entity.
 /// </summary>
 protected CalculatedAsyncBindableBase()
 {
     this._propertyHelper = new CalculatedAsyncPropertyHelper(OnPropertyChanged);
 }
 /// <summary>
 /// Creates a new instance of the entity.
 /// </summary>
 /// <param name="isNotifyOnInvalidate">Indicates whether the notification delegate will be invoked on invalidation.</param>
 protected CalculatedAsyncValidatableBindableBase(bool isNotifyOnInvalidate = true)
     : base(isNotifyOnInvalidate)
 {
     this._propertyHelper = new CalculatedAsyncPropertyHelper(OnPropertyChanged);
 }