使用itext调整添加到pdf文件的字符串的大小

Question

I have the following code :

PdfReader reader = new PdfReader("doc.pdf");
PdfStamper stamper = new PdfStamper(reader,
new FileOutputStream("AttestationTemp.pdf"));
PdfContentByte over = stamper.getOverContent(1);
BaseFont bf = BaseFont.createFont(BaseFont.TIMES_ROMAN, BaseFont.CP1257, false);
over.setFontAndSize(bf, 50);
over.beginText();
ColumnText.showTextAligned(over, Element.ALIGN_LEFT, new Phrase("String"), 110, 384, 0);
over.endText();

try
{
    if (Desktop.isDesktopSupported())
    {
        File myPDF = new File("doc.pdf");
        Desktop.getDesktop().open(myPDF);
    }
}
catch (Exception e)
{
    e.printStackTrace();
}

The problem is that when I change the size of my String using the setFontAndSize method, I get the same result (same small size), so I want to know how to set the size of the string added to the pdf file.

Answer 1

iText offers APIs for PDF content generation at different levels.

There is a very low level API of PdfContentByte methods. At this level you manually add individual content stream operations one-by-one, eg:

PdfContentByte over = ...;
over.setFontAndSize(bf, 50);
over.beginText();
over.setTextMatrix(110, 384);
over.showText("Hello World!");
over.endText();

Then there is the higher level API of ColumnText methods. At this level you construct and style your text using Phrase and Chunk objects and the ColumnText methods create the corresponding content stream operations:

PdfContentByte over = ...;
Phrase phrase = new Phrase("Hello World!", new Font(bf, 50));
ColumnText.showTextAligned(over, Element.ALIGN_LEFT, phrase, 110, 384, 0);

The code of the OP mixes instructions at these levels which in his case results in his font setting call to later be overridden and, therefore, ignored.