docs: def loadFile(self, fileName):
          """
          Load and display the PDF file specified by ``fileName``.
          """
  
          # Test if the file exists.
          if not QtCore.QFile(fileName).exists():
              msg = "File <b>{}</b> does not exist".format(self.qteAppletID())
              self.qteLogger.info(msg)
              self.fileName = None
              return
  
          # Store the file name and load the PDF document with the
          # Poppler library.
          self.fileName = fileName
          doc = popplerqt4.Poppler.Document.load(fileName)
  
          # Enable antialiasing to improve the readability of the fonts.
          doc.setRenderHint(popplerqt4.Poppler.Document.Antialiasing)
          doc.setRenderHint(popplerqt4.Poppler.Document.TextAntialiasing)
  
          # Convert each page to an image, then install that image as the
          # pixmap of a QLabel, and finally insert that QLabel into a
          # vertical layout.
          hbox = QtGui.QVBoxLayout()
          for ii in range(doc.numPages()):
              pdf_img = doc.page(ii).renderToImage()
              pdf_label = self.qteAddWidget(QtGui.QLabel())
              pdf_label.setPixmap(QtGui.QPixmap.fromImage(pdf_img))
              hbox.addWidget(pdf_label)
  
          # Use an auxiliary widget to hold that layout and then place
          # that auxiliary widget into a QScrollView. The auxiliary
          # widget is necessary because QScrollArea can only display a
          # single widget at once.
          tmp = self.qteAddWidget(QtGui.QWidget(self))
          tmp.setLayout(hbox)
          self.qteScroll.setWidget(tmp)