How do I use pagination with Django class based generic ListViews?
I think you ask for information about using pagination with the new class based views since, with traditional function based views, it is easy to find. I found that just by setting the paginate_by variable is enough to activate the pagination. See in Class-based generic views.
For example, in your views.py:
import models
from django.views.generic import ListView
class CarListView(ListView):
model = models.Car # shorthand for setting queryset = models.Car.objects.all()
template_name = 'app/car_list.html' # optional (the default is app_name/modelNameInLowerCase_list.html; which will look into your templates folder for that path and file)
context_object_name = "car_list" #default is object_list as well as model's_verbose_name_list and/or model's_verbose_name_plural_list, if defined in the model's inner Meta class
paginate_by = 10 #and that's it !!
In your template (car_list.html), you can include a pagination section like this (we have some context variables available: is_paginated, page_obj, and paginator).
{# .... **Normal content list, maybe a table** .... #}
{% if car_list %}
<table id="cars">
{% for car in car_list %}
<tr>
<td>{{ car.model }}</td>
<td>{{ car.year }}</td>
<td><a href="/car/{{ car.id }}/" class="see_detail">detail</a></td>
</tr>
{% endfor %}
</table>
{# .... **Now the pagination section** .... #}
{% if is_paginated %}
<div class="pagination">
<span class="page-links">
{% if page_obj.has_previous %}
<a href="/cars?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="/cars?page={{ page_obj.next_page_number }}">next</a>
{% endif %}
</span>
</div>
{% endif %}
{% else %}
<h3>My Cars</h3>
<p>No cars found!!! :(</p>
{% endif %}
{# .... **More content, footer, etc.** .... #}
The page to display is indicated by a GET parameter, simply adding ?page=n, to the URL.
assume, I have a class in app/models.py named FileExam(models.Model):
app/models.py
class FileExam(models.Model):
myfile = models.FileField(upload_to='documents/%Y/%m/%d')
date = models.DateTimeField(auto_now_add=True, blank=True)
teacher_name = models.CharField(max_length=30)
status = models.BooleanField(blank=True, default=False)
app/views.py
from app.models import FileExam
from django.core.paginator import Paginator
from django.core.paginator import EmptyPage
from django.core.paginator import PageNotAnInteger
class FileExamListView(ListView):
model = FileExam
template_name = "app/exam_list.html"
paginate_by = 10
def get_context_data(self, **kwargs):
context = super(FileExamListView, self).get_context_data(**kwargs)
list_exam = FileExam.objects.all()
paginator = Paginator(list_exam, self.paginate_by)
page = self.request.GET.get('page')
try:
file_exams = paginator.page(page)
except PageNotAnInteger:
file_exams = paginator.page(1)
except EmptyPage:
file_exams = paginator.page(paginator.num_pages)
context['list_exams'] = file_exams
return context
Only a little change in the get_context_data and added pagination code from django documentation here
app/templates/app/exam_list.html
normal content list
<table id="exam">
{% for exam in list_exams %}
<tr>
<td>{{ exam.myfile }}</td>
<td>{{ exam.date }}</td>
<td>.....</td>
</tr>
{% endfor %}
</table>
paginate section
{% if is_paginated %}
<ul class="pagination">
{% if page_obj.has_previous %}
<li>
<span><a href="?page={{ page_obj.previous_page_number }}">Previous</a></span>
</li>
{% endif %}
<li class="">
<span>Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}.</span>
</li>
{% if page_obj.has_next %}
<li>
<span><a href="?page={{ page_obj.next_page_number }}">Next</a></span>
</li>
{% endif %}
</ul>
{% else %}
<h3>Your File Exam</h3>
<p>File not yet available</p>
{% endif %}
app/urls.py
urlpatterns = [
url(
r'^$', views.FileExamListView.as_view(), name='file-exam-view'),
),
... ]
We have 2 methods to do this.
First one is simple and just set the class field paginate_by. Nothing need we to do with get_context_data method.
The second method is a little complicated but we can gain more comprehension about pagination and customize complex pagination or several pagination. Let's see it.
It can be done in three steps.
1.Override get_context_data method of your View.
Pass page_keys and pages so that we can iterate the lists and avoid hard-coding .
def get_context_data(self, *, object_list=None, **kwargs):
context = super().get_context_data()
df = pd.DataFrame(list(self.model.objects.all().values()))
ipc = df.groupby('ip')['ip'].count().sort_values(ascending=False)
urlc = df.groupby('url')['url'].count().sort_values(ascending=False).to_dict()
ipc = tuple(ipc.to_dict().items())
urlc = tuple(urlc.items())
pages = []
page_keys = ['page1', 'page2']
for obj, name in zip([urlc, ipc], page_keys):
paginator = Paginator(obj, 20)
page = self.request.GET.get(name)
page_ipc = obj
try:
page_ipc = paginator.page(page)
except PageNotAnInteger:
page_ipc = paginator.page(1)
except EmptyPage:
page_ipc = paginator.page(paginator.num_pages)
pages.append(page_ipc)
context['data'] = zip(pages, page_keys)
return context
2.Customize your sub template.
We define some variables so we can iterate through the pagination list.
pagination.html
{% if is_paginated %}
<ul class="pagination">
{% if page_obj.has_previous %}
<li>
<span><a href="?{{ pname }}={{ page_obj.previous_page_number }}">Previous</a></span>
</li>
{% endif %}
<li class="">
<span>Page {{ page_obj.number }} of {{ page_obj.paginator.num_pages }}.</span>
</li>
{% if page_obj.has_next %}
<li>
<span><a href="?{{ pname }}={{ page_obj.next_page_number }}">Next</a></span>
</li>
{% endif %}
</ul>
{% else %}
<h3>Your File Exam</h3>
<p>File not yet available</p>
{% endif %}
3.Customize outer template.
index.html
{% for foo,name in data %}
<div class="col-md-3 table-responsive">
{% for k,v in foo %}
<tr>
<th>{{ forloop.counter }}</th>
<td>{{ k }}</td>
<td>{{ v }}</td>
</tr>
{% endfor %}
{% include 'pagination.html' with pname=name page_obj=foo %}
</div>
{% endfor %}