private static void SearchTextChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            DecoratedTextBox dt = d as DecoratedTextBox;

            if (dt != null)
            {
                dt.UpdateDecorations();
            }
        }
        private static void HiddenCharsChanged(DependencyObject depObj, DependencyPropertyChangedEventArgs args)
        {
            DecoratedTextBox dt = depObj as DecoratedTextBox;

            if (dt != null)
            {
                dt.UpdateDecorations();
            }
        }