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djangodjango-viewsdjango-generic-views

is_paginated not working properly for class based views in Django


book_list.html

{% extends "base.html" %}
{% block content %}
<h3> Available books </h3>
{% if book_list %}
<ul>
    {% for book in book_list %}
     <li> <a href = "{{ book.get_absolute_url }}">{{book.title }}</a>    <small> by {{book.author }}</small></li>
     <p>{{ book.summary }}
    {% endfor %}
<ul>
{% endif %}
{% if is_paginated %}
  <div class="pagination">
      <span class="page-links">
          {% if page_obj.has_previous %}
              <a href="{{ request.path }}?page={{ page_obj.previous_page_number }}">previous</a>
          {% endif %}
          <span class="page-current">
              Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}.
          </span>
          {% if page_obj.has_next %}
              <a href="{{ request.path }}?page={{ page_obj.next_page_number }}">next</a>
          {% endif %}
      </span>
  </div>
{% else %}
      <h4> pagination not working</h4>
{% endif %}
{% endblock %}

class in views.py :

class BookListView(generic.ListView):
  model = Book
  paginate_by = 2
  queryset =Book.objects.all()

urls.py :

 urlpatterns =[
 url('^$',views.index, name ='index'),  # matching with an empty string 
 url('^books/$',views.BookListView.as_view(),name ='books'), #the one to which I am adding the paginator
 url('^book/(?P<pk>\d+)/$',views.BookDetailView.as_view(),name='book-detail'),

]

Book model :

class Book(models.Model):
  title=models.CharField(max_length=100)
  author = models.ForeignKey('Author',on_delete=models.SET_NULL,null = True)
  summary = models.TextField(max_length=200,help_text="Enter the description")
  isbn = models.CharField('ISBN',max_length=13 ,help_text='13 Character <a href="https://www.isbn-international.org/content/what-isbn">ISBN number</a>' )
  genre = models.ManyToManyField(Genre,help_text = 'selct a genre for this book')

  class Meta:
     ordering =["title"]
  def __str__(self):
     return self.title

  def get_absolute_url(self):
     return reverse('book-detail',args=[str(self.id)] )  

The book_list gets rendered perfectly, the problem is with the paginator, the is_paginated condition is not working and it executes the else statement, I have been trying for more than 3 hours, but couldn't find a solution, What Am I missing here ?
Django version : 1.11.2 Python : 3.5

Edit : update 1: The problem was the paginate_by value was two, and the total items to display was also two hence it didn't initiate the is_paginated tag,It worked fine when I added one item more than paginate_by value.


Solution

  • use this, you had some problem with the if condition

    {% extends "base.html" %}
    {% block content %}
    <h3> Available books </h3>
    {% if object_list %}
        <ul>
            {% for book in object_list %}
             <li> <a href = "{{ book.get_absolute_url }}">{{book.title }}</a>    <small> by {{book.author }}</small></li>
             <p>{{ book.summary }}
            {% endfor %}
        <ul>
    
        {% if is_paginated %}
          <div class="pagination">
              <span class="page-links">
                  {% if page_obj.has_previous %}
                      <a href="{{ request.path }}?page={{ page_obj.previous_page_number }}">previous</a>
                  {% endif %}
                  <span class="page-current">
                      Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}.
                  </span>
                  {% if page_obj.has_next %}
                      <a href="{{ request.path }}?page={{ page_obj.next_page_number }}">next</a>
                  {% endif %}
              </span>
          </div>
        {% else %}
              <h4> pagination not working</h4>
        {% endif %}
            {% else %}
            <h4> No book</h4>
    {% endif %}
    {% endblock %}