void OnExport(object sender, EventArgs e)
        {
            ExportTarget exportType  = GetCurrentExportType();
            string       fileName    = "grid." + exportType.ToString().ToLower();
            IPathService pathServise = GlobalServices.Instance.GetService <IPathService>();

            if (pathServise == null)
            {
                return;
            }

            string filePath = pathServise.GetAbsolutePath(fileName);

            pathServise.EnsurePathExists(filePath);

            using (FileStream stream = new FileStream(filePath, FileMode.Create, FileAccess.Write, FileShare.Read)) {
                if (grid.ExportToExcel(stream, exportType))
                {
                    txtPath.Text = stream.AbsolutePath;
                }
                else
                {
                    txtPath.Text = String.Empty;
                    DisplayAlert("GridDemo", "Make sure you have an application for opening " + exportType.ToString() + " files.", "Cancel");
                }
            }
        }