public static bool ShowInputTimeIntervalDialog(out double retIntervalSeconds, Window owner = null, string descriptionText = null)
        {
            retIntervalSeconds = 0;

            var dlg = new TimeIntervalDialog();

            if (string.IsNullOrEmpty(descriptionText) == false)
            {
                dlg.GuiTextBlockTextDescription.Text = descriptionText;
            }

            if (owner != null)
            {
                dlg.Owner = owner;
            }

            if (dlg.ShowDialog() == true)
            {
                retIntervalSeconds = dlg.__ResultInSeconds;
                return(true);
            }

            return(false);
        }