private void GoToPreviousPageExecuted(Object param)
 {
     if (wizard != null)
     {
         DesignerOperations.GoToPreviousPage(wizard);
     }
 }
        private void OnGoToPreviousPage(object sender, MenuActionEventArgs e)
        {
            ModelItem wizard = GetWizard(e.Selection.PrimarySelection);

            if (wizard != null)
            {
                DesignerOperations.GoToPreviousPage(wizard);
            }
        }