实例化类内部的对象

Question

我试图理解为什么我不能访问在类内部实例化的对象上的方法。例如，我试图构建一个利用python pptx库的脚本，我希望将整个幻灯片创建封装在一个类中，以对其进行抽象，并根据我的配置使其更加可重用

class Builder():

    def __init__(self, template='template.pptx', output_file='out.pptx'):
        self.cust_name = ''
        self.author = ''
        self.job_title = ''
        self.present_date = ''
        self.assessment_type = ''
        self.template = template
        self.agenda = ['Overview','Resources']
        self.outfile = output_file
        self.prs = Presentation('template.pptx') <--- This is what im referring to.

    def addAgendaSlide(self):
        agenda_slide = self.prs.add_slide(self.prs.slide_layouts[AGENDA]) <-- When trying to access this
        agenda_slide.shapes.title.text = 'Agenda'
        agenda_slide.placeholders[10].text = 'A test Agenda slide'
        agenda_slide.placeholders[15].top = STANDARD_TOP
        agenda_slide.placeholders[15].left = STANDARD_LEFT
        agenda_slide.placeholders[15].width = 8229600
        agenda_slide.placeholders[15].height = 4572000
        for para in self.agenda:
            p = agenda_slide.placeholders[15].text_frame.add_paragraph()
            p.text = para

Traceback (most recent call last):
  File "test.py", line 19, in <module>
test.addAgendaSlide()
  File "/dev/pythonpptx/DocMaker/Slides.py", line 89, in addAgendaSlide
agenda_slide = self.prs.add_slide(self.prs.slide_layouts[AGENDA])
AttributeError: 'Presentation' object has no attribute 'add_slide'

如果我在类外使用相同的代码位，它就可以正常工作。我确实在这个类中有其他好的方法，似乎是我对Presentation（）位的实现把我搞砸了

以下工作很好：

prs = Presentation('template.pptx')
agenda_slide = prs.slides.add_slide(prs.slide_layouts[AGENDA])
agenda_slide.shapes.title.text = 'Agenda'
agenda_slide.placeholders[15].top = STANDARD_TOP
agenda_slide.placeholders[15].left = STANDARD_LEFT
agenda_slide.placeholders[15].width = 8229600
agenda_slide.placeholders[15].height = 4572000
prs.save('out.pptx')

Answer 1

我认为你的问题在于你忘记添加slides，如下所示：

agenda_slide = self.prs.slides.add_slide(self.prs.slide_layouts[AGENDA])

而不是

agenda_slide = self.prs.add_slide(self.prs.slide_layouts[AGENDA])