How to customize print preview window in WPF DataGrid (SfDataGrid)?

<Grid>
        <Grid Background="#FFF7F7F7">
            <Grid.RowDefinitions>
                <RowDefinition Height="Auto" />
                <RowDefinition Height="*" />
                <RowDefinition Height="Auto" />
            </Grid.RowDefinitions>
…
            <Border Background="#FFDBDBDB" DataContext="{Binding ElementName=PrintPreviewArea}">
                <StackPanel Margin="10,5"
                            HorizontalAlignment="Center"
                            Orientation="Horizontal">...
                    
                    <Button Height="38"
                            Margin="10,3"
                            Click="OnExportPDFButtonClick"
                            Content="Export To PDF"
                            Style="{StaticResource ButtonStyle}"
                            ToolTip="Export To PDF" />
                    <Button Height="38"
                            Margin="10,3"
                            Click="OnExporttoExcelButtonClick"
                            Content="Export To Excel"
                            Style="{StaticResource ButtonStyle}"
                            ToolTip="Export To Excel" />
…
           </StackPanel>
       </Border>
 ... 
</Grid>                   

void OnExporttoExcelButtonClick(object sender, RoutedEventArgs e)
{
    var dataGrid = Grid;
    if (dataGrid == null) return;
    try
    {
        //Setting the Exporting Options by craeting a instance for ExcelExportingOptions.
        var exportingOptions =new  ExcelExportingOptions();
        exportingOptions.ExportAllPages = true;
        exportingOptions.ExportStackedHeaders = true;
        //Below code exports datagrid to excel and returns Excel Engine.
        var excelEngine = dataGrid.ExportToExcel(dataGrid.View, exportingOptions);
 
        var workBook = excelEngine.Excel.Workbooks[0];
 
        //saving the workbook using savefiledialog.
        SaveFileDialog sfd = new SaveFileDialog
        {
            FilterIndex = 2,
            Filter = "Excel 97 to 2003 Files(*.xls)|*.xls|Excel 2007 to 2010 Files(*.xlsx)|*.xlsx"
        };
 
        if (sfd.ShowDialog() == true)
        {
            using (Stream stream = sfd.OpenFile())
            {
                if (sfd.FilterIndex == 1)
                    workBook.Version = ExcelVersion.Excel97to2003;
                else
                    workBook.Version = ExcelVersion.Excel2010;
                workBook.SaveAs(stream);
            }
 
            //Message box confirmation to view the created spreadsheet.
            if (MessageBox.Show("Do you want to view the workbook?", "Workbook has been created",
                                MessageBoxButton.YesNo, MessageBoxImage.Information) == MessageBoxResult.Yes)
            {
                //Launching the Excel file using the default Application.[MS Excel Or Free ExcelViewer]
                System.Diagnostics.Process.Start(sfd.FileName);
            }
        }
    }
    catch (Exception)
    {
 
    }
}
 
void OnExportPDFButtonClick(object sender, RoutedEventArgs e)
{
    var dataGrid = Grid;
    if (dataGrid == null) return;
    try
    {
        var options = new PdfExportingOptions();
        options.FitAllColumnsInOnePage = true;
        var document = dataGrid.ExportToPdf(options);
 
        SaveFileDialog sfd = new SaveFileDialog
        {
            Filter = "PDF Files(*.pdf)|*.pdf"
        };
 
        if (sfd.ShowDialog() == true)
        {
            using (Stream stream = sfd.OpenFile())
            {
                document.Save(stream);
            }
 
            //Message box confirmation to view the created Pdf file.
            if (MessageBox.Show("Do you want to view the Pdf file?", "Pdf file has been created",
                                MessageBoxButton.YesNo, MessageBoxImage.Information) == MessageBoxResult.Yes)
            {
                //Launching the Pdf file using the default Application.
                System.Diagnostics.Process.Start(sfd.FileName);
            }
        }
    }
    catch (Exception)
    {
 
    }
}