Django - 混合ListView和CreateView

问题描述

我想用表单创建一个页面，每次提交表单时，它都会在表单下面添加一个项目。

我可以使用2个页面使其工作：

• 使用mixin CreateView 添加一页项目


• 一页 ListView 列表。

---

但是我试图将表单和列表放在同一页面上。所以我试图用mixin创建一个类：

  class FormAndListView（ListView，CreateView）：
 pass 
  

然后我使用了这个类：

  FormAndListView.as_view（
 queryset = PdfFile.objects.order_by（'id'），
 context_object_name ='all_PDF'，
 success_url ='listview' 
 form_class = UploadFileForm，
 template_name ='textfrompdf / index.html'，）），
  

但是当我尝试加载页面时，我会收到错误：异常值：'FormAndListView'对象没有属性'object'

 追溯：
文件C：\Program Files\Python_2.7\lib\site-packages\django\ core_\\handlers\base.pyin get_response 
 111. response = callback（request，* callback_args，** callback_kwargs）
文件C：\Program Files\Python_2.7\ lib\site- package \django\views\generic\base.py在视图
 47. return self.dispatch（request，* args，** kwargs）
文件C：\Program文件$ pa $ b中的\Python_2.7\lib\site-packages\django\views\generic\base.py68.返回处理程序（request，* args，** kwargs）
文件C：\Program Files\Python_2.7\lib\site-packages\django\views\generic\list.py在get 
 122. return self.render_to_response （上下文）
在render_to_response中的文件C：\Program Files\Python_2.7\lib\site- packages\django\views\generic\base.py
 94 。template = self.get_template_names（），
文件C：\Program Files\Python_2.7\lib\site- packages\django\views\generic\list.py get_template_names 
 134. names = super（MultipleObjectTemplateResponseMixin，self）.get_template_names（）
文件C：\Program Files\Python_2.7\lib\site-packages\django\views\generic\detail.py在get_template_names 
 122.如果self.object和self。 template_name_field：
 
异常类型：/ PDF / 
中的AttributeError异常值：'FormAndListView'对象没有属性'对象'
  

我不知道如何调试。在哪里开始？

解决方案

我发现答案有两个问题：

• ListView和CreateView是低级
  级别混合的高级混合。但是这些较低级别的混合不兼容。


• View类直接调用render_to_response（），但在我的场景中，有2个视图类，render_to_response（）只应该被调用一次$ / $>
  
  

  ---

  
  
  

  我能够解决这个问题，使用以下步骤：

  
  
  

  我使用较低级别的mixins而不是调用ListView和CreateView。另外我调用了显式的BaseCreateView和BaseListView，我从中提取窗体和object_list

    class FormAndListView（BaseCreateView，BaseListView，TemplateResponseMixin） ：
   def get（self，request，* args，** kwargs）：
   formView = BaseCreateView.get（self，request，* args，** kwargs）
   listView = BaseListView.get （self，request，* args，** kwargs）
   formData = formView.context_data ['form'] 
   listData = listView.context_data ['object_list'] 
   return render_to_response（'textfrompdf / index.html'，{'form'：formData，'all_PDF'：listData}，
   context_instance = RequestContext（request））
    

  它不干净，但它的作品！

  
  

  I'm want to create one page with a form, and every time I submit the form it adds an item to the list below the form.

  I can make it work using 2 pages:

  • one page using the mixin CreateView to add items
  • one page ListView to have the list.

  ---

  But I'm trying to have the form and the list on the same page. So I tried to create a class with both mixin:

  class FormAndListView(ListView, CreateView):
      pass
  

  Then I've used this class:

  FormAndListView.as_view(
      queryset=PdfFile.objects.order_by('id'),
      context_object_name='all_PDF',
      success_url = 'listview',
      form_class = UploadFileForm,
      template_name='textfrompdf/index.html',)),
  

  But when I try to load the page, I get the error: Exception Value: 'FormAndListView' object has no attribute 'object'

  Traceback:
  File "C:\Program Files\Python_2.7\lib\site-packages\django\core\handlers\base.py" in get_response
    111.                         response = callback(request, *callback_args, **callback_kwargs)
  File "C:\Program Files\Python_2.7\lib\site-packages\django\views\generic\base.py" in view
    47.             return self.dispatch(request, *args, **kwargs)
  File "C:\Program Files\Python_2.7\lib\site-packages\django\views\generic\base.py" in dispatch
    68.         return handler(request, *args, **kwargs)
  File "C:\Program Files\Python_2.7\lib\site-packages\django\views\generic\list.py" in get
    122.         return self.render_to_response(context)
  File "C:\Program Files\Python_2.7\lib\site-packages\django\views\generic\base.py" in render_to_response
    94.             template = self.get_template_names(),
  File "C:\Program Files\Python_2.7\lib\site-packages\django\views\generic\list.py" in get_template_names
    134.             names = super(MultipleObjectTemplateResponseMixin, self).get_template_names()
  File "C:\Program Files\Python_2.7\lib\site-packages\django\views\generic\detail.py" in get_template_names
    122.         if self.object and self.template_name_field:
  
  Exception Type: AttributeError at /PDF/
  Exception Value: 'FormAndListView' object has no attribute 'object'
  

  I've no idea how to debug that. Where to start?

  解决方案

  I found the answer, there is 2 problems:

  • ListView and CreateView are "high level" mixin which aggregate "lowerlevel" mixins. But these lower level mixins are not compatible together.
  • The View class calls directly the render_to_response(), but in my scenario, there is 2 view class and render_to_response() should only be called once at the end.

  ---

  I was able "solve" this issue using the following steps:

  Instead of calling ListView and CreateView, I used lower level mixins. Moreover I called explicitly BaseCreateView and BaseListView from which I "extracted" the form and object_list

  class FormAndListView(BaseCreateView, BaseListView, TemplateResponseMixin):
      def get(self, request, *args, **kwargs):
          formView = BaseCreateView.get(self, request, *args, **kwargs)
          listView = BaseListView.get(self, request, *args, **kwargs)
          formData = formView.context_data['form']
          listData = listView.context_data['object_list']
          return render_to_response('textfrompdf/index.html', {'form' : formData, 'all_PDF' : listData},
                             context_instance=RequestContext(request))
  

  It's not clean but it works!

  这篇关于Django - 混合ListView和CreateView的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！