def generate_pdf(self):
        """Generate a PDF from the displayed content."""
        printer = QtGui.QPrinter(QtGui.QPrinter.HighResolution)
        printer.setPageSize(QtGui.QPrinter.A4)
        printer.setColorMode(QtGui.QPrinter.Color)
        printer.setOutputFormat(QtGui.QPrinter.PdfFormat)
        report_path = unique_filename(suffix='.pdf')
        printer.setOutputFileName(report_path)
        self.print_(printer)
        url = QtCore.QUrl.fromLocalFile(report_path)
        # noinspection PyTypeChecker,PyCallByClass,PyArgumentList
        QtGui.QDesktopServices.openUrl(url)
Generate a PDF from the displayed content.