Xceed.Wpf.Toolkit.ChildWindow.OnTopPropertyChanged C# (CSharp) Method

    protected override void OnTopPropertyChanged( double oldValue, double newValue )
    {
      base.OnTopPropertyChanged( oldValue, newValue );

      _hasWindowContainer = ( VisualTreeHelper.GetParent( this ) as WindowContainer ) != null;
      if( !_hasWindowContainer )
      {
          Top = GetRestrictedTop();
        ProcessMove( 0, newValue - oldValue );
      }
    }

        private static void OnTopPropertyChanged(DependencyObject obj, DependencyPropertyChangedEventArgs e)
        {
            ChildWindow childWindow = obj as ChildWindow;

            if (childWindow != null)
            {
                childWindow.OnTopPropertyChanged(( double )e.OldValue, ( double )e.NewValue);
            }
        }