I have used iText to fill data into existing AcroForm fields in a PDF.

I am now looking for a solution to add new AcroForm fields to a PDF. Is this possible with iText? If so, how can I do this?

Posted on StackOverflow on Nov 30, 2014 by Peter

This is documented in the official documentation, more specifically in the SubmitForm example. Additionally, I've written a simple example called AddField. It adds a button field at a specific position defined by new Rectangle(36, 700, 36, 30). Here is the code adapted for iText 7:

protected void manipulatePdf(String dest) throws Exception {
        PdfDocument pdfDoc = new PdfDocument(new PdfReader(SRC), new PdfWriter(DEST));
        PdfAcroForm form = PdfAcroForm.getAcroForm(pdfDoc, true);

        PdfButtonFormField button = PdfFormField.createPushButton(pdfDoc, new Rectangle(36, 700, 36, 30), "post", "POST");
        button.setBackgroundColor(ColorConstants.GRAY);
        button.setValue("POST");
        button.setAction(PdfAction.createSubmitForm("http://itextpdf.com:8180/book/request", null,
                PdfAction.SUBMIT_HTML_FORMAT | PdfAction.SUBMIT_COORDINATES));
        button.setVisibility(PdfFormField.VISIBLE_BUT_DOES_NOT_PRINT);

        form.addField(button);

        pdfDoc.close();
    }

As you can see, you need to create a PdfButtonFormField object and then use a PdfAcroForm instance to add the field.

Click this link if you want to see how to answer this question in iText 5.