iText AddImage() to specific page - itext

Question

I'm having a problem trying to locate a PdfContentByte directly into an specific page. My problem is: I need to add an Image for each page (That works) and need to add a QRCode to each of the pages at the right bottom corner but this works only for the first Page and I don't know how to repeat it on the other ones.
This is my code:
public string GeneratePDFDocument(Atomic.Development.Montenegro.Data.Entities.Document document, Stamp stamp)
{
string filename = #"C:\Users\Sheldon\Desktop\Pdf.Pdf";
FileStream fs = new FileStream(filename, FileMode.Create);
iTextSharp.text.Document pdfDocument = new iTextSharp.text.Document(PageSize.LETTER, PAGE_LEFT_MARGIN, PAGE_RIGHT_MARGIN, PAGE_TOP_MARGIN, PAGE_BOTTOM_MARGIN);
iTextSharp.text.pdf.PdfWriter writer = iTextSharp.text.pdf.PdfWriter.GetInstance(pdfDocument, fs);
pdfDocument.Open();
int count = document.Pages.Count;
foreach (Page page in document.Pages)
{
Image img = Image.GetInstance(page.Image);
img.ScaleToFit(PageSize.LETTER.Width-(PAGE_LEFT_MARGIN + PAGE_RIGHT_MARGIN), PageSize.LETTER.Height-(PAGE_TOP_MARGIN + PAGE_BOTTOM_MARGIN));
pdfDocument.Add(img);
PlaceCodeBar(writer);
}
pdfDocument.Close();
writer.Close();
fs.Close();
return filename;
}
private static void PlaceCodeBar(iTextSharp.text.pdf.PdfWriter writer)
{
String codeText = "TEXT TO ENCODE";
iTextSharp.text.pdf.BarcodePDF417 pdf417 = new iTextSharp.text.pdf.BarcodePDF417();
pdf417.SetText(codeText);
Image img = pdf417.GetImage();
iTextSharp.text.pdf.BarcodeQRCode qrcode = new iTextSharp.text.pdf.BarcodeQRCode(codeText, 1, 1, null);
img = qrcode.GetImage();
iTextSharp.text.pdf.PdfContentByte cb = writer.DirectContent;
cb.SaveState();
cb.BeginText();
img.SetAbsolutePosition(PageSize.LETTER.Width-PAGE_RIGHT_MARGIN-img.ScaledWidth, PAGE_BOTTOM_MARGIN);
cb.AddImage(img);
cb.EndText();
cb.RestoreState();
}

Answer 1

So add it in your foreach (Page...) loop:
foreach (Page page in document.Pages)
{
Image img = Image.GetInstance(page.Image);
img.ScaleToFit(PageSize.LETTER.Width-(PAGE_LEFT_MARGIN + PAGE_RIGHT_MARGIN), PageSize.LETTER.Height-(PAGE_TOP_MARGIN + PAGE_BOTTOM_MARGIN));
pdfDocument.Add(img);
PlaceCodeBar(writer);
}
If this is a second pass on the same PDF (you've closed it then opened it again), use a PdfStamper rather than a PdfWriter. You can then get the direct content of each page rather than the one direct content that is reused (and reset) for each page.
PS: Drop the BeginText() and EndText() calls. Those operators should only be used when actually drawing text/setting fonts/etc. No line art. No images. The SaveState()/RestoreState() are good though. Definitely keep those.

Answer 2

I just figure out how to solve the problem. Just delete the cb.SaveState() and cb.RestoreState() and it put the image on the page is actually active.