Reportlab第x页，共y页编号画布和图像

Question

我一直在使用在http://code.activestate.com/recipes/546511/给出的reportlab NumberedCanvas。然而，当我试图构建一个包含图像流的PDF文件时，图像没有显示出来，尽管有足够的垂直空间来容纳图像。有什么解决办法吗？在

Answer 1

请参见my new, improved recipe，其中包括一个简单的图像测试。以下是配方的摘录（省略了测试代码）：

from reportlab.pdfgen import canvas
from reportlab.lib.units import mm

class NumberedCanvas(canvas.Canvas):
    def __init__(self, *args, **kwargs):
        canvas.Canvas.__init__(self, *args, **kwargs)
        self._saved_page_states = []

    def showPage(self):
        self._saved_page_states.append(dict(self.__dict__))
        self._startPage()

    def save(self):
        """add page info to each page (page x of y)"""
        num_pages = len(self._saved_page_states)
        for state in self._saved_page_states:
            self.__dict__.update(state)
            self.draw_page_number(num_pages)
            canvas.Canvas.showPage(self)
        canvas.Canvas.save(self)

    def draw_page_number(self, page_count):
        self.setFont("Helvetica", 7)
        self.drawRightString(200*mm, 20*mm,
            "Page %d of %d" % (self._pageNumber, page_count))