有啥方法可以将过滤后的查询集传递给 Django 分页？

Posted 2023-02-23

【中文标题】有啥方法可以将过滤后的查询集传递给 Django 分页？

【英文标题】：Is there any way I can pass a filtered query set into Django's pagination?有什么方法可以将过滤后的查询集传递给 Django 分页？

【发布时间】：2021-02-09 18:37:11

【问题描述】：

view.py

def quiz(request):

    question_topic = request.POST.getlist("topic_checkbox") # Retrieves list of topics selected by user
    question_list = Quiz.objects.filter(Topic_name__in = question_topic) #filters out questions by topics

    paginator = Paginator(question_list,1) # when i pass all the objects rather than the filtered query set it seems to work but when i paginate with the filtered queryset only the first page loads
    page = request.GET.get('page')
    try:
        question_list = paginator.page(page)
    except PageNotAnInteger:
        question_list = paginator.page(1)
    except EmptyPage:
        question_list = paginator.page(paginator.num_pages)

    return render(request,"Quiz/quiz_home.html","question_list":question_list)

quiz_home.html

% block content %
        % for q in question_list % # loops through the filtered queryset
            % if question_list.has_next %
                <h3>Question q.id</h3>
                <form method="POST" action="?page= question_list.next_page_number ">% csrf_token %
# The form should enable me to gather the users input whilst simultaneoulsy going to the next question in the for loop. But when question sumbitted the next page is blank showing no contents
                    % if q.picture %
                        <img src="/media/q.picture"> <br>
                    % endif %
                    q.id.) </label><label id="question_text">q.question</label><br>
                    <input type="hidden" id= "q_id" name="q_id" value="q.id">
                    <input type="hidden" id= "topic" name="topic" value="q.topic">
                    <input type="radio" id="opt1" name="options" value="q.option1" required> q.option1 <br>
                    <input type="radio" id="opt2" name="options" value="q.option2" required> q.option2 <br>
                    <input type="radio" id="opt3" name="options" value="q.option3" required> q.option3 <br>
                    <hr>
                    <input type="submit" id="mybtn" value="Submit"> #once clicked it should paginate to next page
                </form>
            % else %
                <hr>
                <form action="/home/">% csrf_token %
                    <input type="submit" name="End" value="End">
                </form>
            % endif %
        % endfor %
    % endblock %

基本上我试图根据用户选择的主题过滤掉问题。然后对这个问题查询集进行分页，以便每一页显示一个问题。

【参考方案1】：

我给你看一个分页实例：

views.py

class CategoryDetail(ListView):  
    model = Task  
    template_name = 'category/category_detail.html'  
    context_object_name = 'task'  
    paginate_by = 5

    def get_queryset(self):
        self.category = get_object_or_404(Category,
                                          pk=self.kwargs['pk'])  
        return Task.objects.filter(category=self.category).order_by('-id')  

    def get_context_data(self, *, object_list=None, **kwargs):
        context = super(CategoryDetail, self).get_context_data(**kwargs)
        self.category = get_object_or_404(Category, pk=self.kwargs['pk'])
        # context['category'] = self.category
        return context

类别/category_detail.html

....

 <div class="card-footer py-4">
                % if is_paginated %
              <nav aria-label="...">
                <ul class="pagination justify-content-end mb-0">
                    % if page_obj.has_previous %
                  <li class="page-item">
                    <a class="page-link" href="?page= page_obj.previous_page_number " tabindex="-1">
                      <i class="fas fa-angle-left"></i>
                      <span class="sr-only">Previous</span>
                    </a>
                  </li>

                   % else %

                     <li class="page-item disabled">
                    <a class="page-link" href="#" tabindex="-1">
                      <i class="fas fa-angle-left"></i>
                      <span class="sr-only">Previous</span>
                    </a>
                  </li>

                    % endif %

                    % for i in paginator.page_range %
                    % if page_obj.number == i %
                  <li class="page-item active">
                    <a class="page-link" href="#">  i  </a>
                  </li>
                     % else %
                  <li class="page-item">
                    <a class="page-link" href="?page= i "> i <span class="sr-only">(current)</span></a>
                  </li>
                    % endif %
                    % endfor %

                     % if page_obj.has_next %
                  <li class="page-item">
                    <a class="page-link" href="?page= page_obj.next_page_number ">
                      <i class="fas fa-angle-right"></i>
                      <span class="sr-only">Next</span>
                    </a>
                  </li>

                    % else %

                     <li class="page-item disabled">
                    <a class="page-link" href="#">
                      <i class="fas fa-angle-right"></i>
                      <span class="sr-only">Next</span>
                    </a>
                  </li>
                    % endif %

                </ul>
              </nav>
                % endif %
            </div>

Django 已经有了现成的分页结构。您可以在您要使用的 Html 文件中使用它。

【讨论】：

ListView 在我们有表单时不起作用，对吗？我正在尝试对过滤后的查询集 question_list = Quiz.objects.filter(Topic_name__in = question_topic) 进行分页，同时还从每个页面发布数据。一个使用基于函数的视图的例子将不胜感激。