I'm not sure to understand exactly what you want. I assume you want to take a screen shot ? and then put this picture into a PDF document.
To take a screenshot with Qt, have a look at this :
http://doc.qt.nokia.com/4.0/widgets-screenshot.html
This will show you how to take a screenshot (using QDesktopWidget) and get a QPixmap
.
You can then display this QPixmap
into a QTextDocument (see QTextDocument::addResource) and print this document into a PDF file. Something like this :
QPrinter MyPrinter(QPrinter::HighResolution);
MyPrinter.setOutputFormat(QPrinter::PdfFormat);
MyPrinter.setOutputFileName("test.pdf");
MyPrinter.setPageSize(QPrinter::Letter);
MyPrinter.setColorMode(QPrinter::GrayScale);
MyPrinter.setOrientation(QPrinter::Landscape);
MyTextDocument.print(&MyPrinter);