Django provides a few classes that help you manage paginated data – that is, data that’s split across several pages, with “Previous/Next” links. These classes live in django/core/paginator.py
.
Give Paginator
a list of objects, plus the number of items you’d like to have on each page, and it gives you methods for accessing the items for each page:
>>> from django.core.paginator import Paginator >>> objects = ['john', 'paul', 'george', 'ringo'] >>> p = Paginator(objects, 2) >>> p.count 4 >>> p.num_pages 2 >>> type(p.page_range) # `<type 'rangeiterator'>` in Python 2. <class 'range_iterator'> >>> p.page_range range(1, 3) >>> page1 = p.page(1) >>> page1 <Page 1 of 2> >>> page1.object_list ['john', 'paul'] >>> page2 = p.page(2) >>> page2.object_list ['george', 'ringo'] >>> page2.has_next() False >>> page2.has_previous() True >>> page2.has_other_pages() True >>> page2.next_page_number() Traceback (most recent call last): ... EmptyPage: That page contains no results >>> page2.previous_page_number() 1 >>> page2.start_index() # The 1-based index of the first item on this page 3 >>> page2.end_index() # The 1-based index of the last item on this page 4 >>> p.page(0) Traceback (most recent call last): ... EmptyPage: That page number is less than 1 >>> p.page(3) Traceback (most recent call last): ... EmptyPage: That page contains no results
Note
Note that you can give Paginator
a list/tuple, a Django QuerySet
, or any other object with a count()
or __len__()
method. When determining the number of objects contained in the passed object, Paginator
will first try calling count()
, then fallback to using len()
if the passed object has no count()
method. This allows objects such as Django’s QuerySet
to use a more efficient count()
method when available.
Paginator
in a viewHere’s a slightly more complex example using Paginator
in a view to paginate a queryset. We give both the view and the accompanying template to show how you can display the results. This example assumes you have a Contacts
model that has already been imported.
The view function looks like this:
from django.core.paginator import Paginator, EmptyPage, PageNotAnInteger from django.shortcuts import render def listing(request): contact_list = Contacts.objects.all() paginator = Paginator(contact_list, 25) # Show 25 contacts per page page = request.GET.get('page') try: contacts = paginator.page(page) except PageNotAnInteger: # If page is not an integer, deliver first page. contacts = paginator.page(1) except EmptyPage: # If page is out of range (e.g. 9999), deliver last page of results. contacts = paginator.page(paginator.num_pages) return render(request, 'list.html', {'contacts': contacts})
In the template list.html
, you’ll want to include navigation between pages along with any interesting information from the objects themselves:
{% for contact in contacts %} {# Each "contact" is a Contact model object. #} {{ contact.full_name|upper }}<br /> ... {% endfor %} <div class="pagination"> <span class="step-links"> {% if contacts.has_previous %} <a href="?page={{ contacts.previous_page_number }}">previous</a> {% endif %} <span class="current"> Page {{ contacts.number }} of {{ contacts.paginator.num_pages }}. </span> {% if contacts.has_next %} <a href="?page={{ contacts.next_page_number }}">next</a> {% endif %} </span> </div>
Paginator
objectsThe Paginator
class has this constructor:
class Paginator(object_list, per_page, orphans=0, allow_empty_first_page=True)
[source]
object_list
A list, tuple, QuerySet
, or other sliceable object with a count()
or __len__()
method. For consistent pagination, QuerySet
s should be ordered, e.g. with an order_by()
clause or with a default ordering
on the model.
Performance issues paginating large QuerySet
s
If you’re using a QuerySet
with a very large number of items, requesting high page numbers might be slow on some databases, because the resulting LIMIT
/OFFSET
query needs to count the number of OFFSET
records which takes longer as the page number gets higher.
per_page
orphans
optional argument below).orphans
orphans
, then those items will be added to the previous page (which becomes the last page) instead of leaving the items on a page by themselves. For example, with 23 items, per_page=10
, and orphans=3
, there will be two pages; the first page with 10 items and the second (and last) page with 13 items. orphans
defaults to zero, which means pages are never combined and the last page may have one item.allow_empty_first_page
False
and object_list
is empty, then an EmptyPage
error will be raised.Paginator.page(number)
[source]
Returns a Page
object with the given 1-based index. Raises InvalidPage
if the given page number doesn’t exist.
Paginator.count
The total number of objects, across all pages.
Note
When determining the number of objects contained in object_list
, Paginator
will first try calling object_list.count()
. If object_list
has no count()
method, then Paginator
will fallback to using len(object_list)
. This allows objects, such as Django’s QuerySet
, to use a more efficient count()
method when available.
Paginator.num_pages
The total number of pages.
Paginator.page_range
A 1-based range iterator of page numbers, e.g. yielding [1, 2, 3, 4]
.
InvalidPage
exceptionsexception InvalidPage
[source]
A base class for exceptions raised when a paginator is passed an invalid page number.
The Paginator.page()
method raises an exception if the requested page is invalid (i.e., not an integer) or contains no objects. Generally, it’s enough to catch the InvalidPage
exception, but if you’d like more granularity, you can catch either of the following exceptions:
exception PageNotAnInteger
[source]
Raised when page()
is given a value that isn’t an integer.
exception EmptyPage
[source]
Raised when page()
is given a valid value but no objects exist on that page.
Both of the exceptions are subclasses of InvalidPage
, so you can handle them both with a simple except InvalidPage
.
Page
objectsYou usually won’t construct Page
objects by hand – you’ll get them using Paginator.page()
.
class Page(object_list, number, paginator)
[source]
A page acts like a sequence of Page.object_list
when using len()
or iterating it directly.
Page.has_next()
[source]
Returns True
if there’s a next page.
Page.has_previous()
[source]
Returns True
if there’s a previous page.
Page.has_other_pages()
[source]
Returns True
if there’s a next or previous page.
Page.next_page_number()
[source]
Returns the next page number. Raises InvalidPage
if next page doesn’t exist.
Page.previous_page_number()
[source]
Returns the previous page number. Raises InvalidPage
if previous page doesn’t exist.
Page.start_index()
[source]
Returns the 1-based index of the first object on the page, relative to all of the objects in the paginator’s list. For example, when paginating a list of 5 objects with 2 objects per page, the second page’s start_index()
would return 3
.
Page.end_index()
[source]
Returns the 1-based index of the last object on the page, relative to all of the objects in the paginator’s list. For example, when paginating a list of 5 objects with 2 objects per page, the second page’s end_index()
would return 4
.
Page.object_list
The list of objects on this page.
Page.number
The 1-based page number for this page.
Page.paginator
The associated Paginator
object.
© Django Software Foundation and individual contributors
Licensed under the BSD License.
https://docs.djangoproject.com/en/1.11/topics/pagination/