Pagination
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
.
Example
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) <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.
Using Paginator
in a view
Here’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 EmptyPage, PageNotAnInteger, Paginator 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') contacts = paginator.get_page(page) 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=1">« first</a> <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> <a href="?page={{ contacts.paginator.num_pages }}">last »</a> {% endif %} </span> </div>
Paginator
objects
The Paginator
class has this constructor:
-
class Paginator(object_list, per_page, orphans=0, allow_empty_first_page=True)
[source]
Required arguments
-
object_list
-
A list, tuple,
QuerySet
, or other sliceable object with acount()
or__len__()
method. For consistent pagination,QuerySet
s should be ordered, e.g. with anorder_by()
clause or with a defaultordering
on the model.Performance issues paginating large
QuerySet
sIf you’re using a
QuerySet
with a very large number of items, requesting high page numbers might be slow on some databases, because the resultingLIMIT
/OFFSET
query needs to count the number ofOFFSET
records which takes longer as the page number gets higher. -
per_page
- The maximum number of items to include on a page, not including orphans (see the
orphans
optional argument below).
Optional arguments
-
orphans
- Use this when you don’t want to have a last page with very few items. If the last page would normally have a number of items less than or equal to
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
, andorphans=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
- Whether or not the first page is allowed to be empty. If
False
andobject_list
is empty, then anEmptyPage
error will be raised.
Methods
-
Paginator.get_page(number)
[source] -
New in Django 2.0.
Returns a
Page
object with the given 1-based index, while also handling out of range and invalid page numbers.If the page isn’t a number, it returns the first page. If the page number is negative or greater than the number of pages, it returns the last page.
It raises an exception (
EmptyPage
) only if you specifyPaginator(..., allow_empty_first_page=False)
and theobject_list
is empty.
-
Paginator.page(number)
[source] -
Returns a
Page
object with the given 1-based index. RaisesInvalidPage
if the given page number doesn’t exist.
Attributes
-
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 callingobject_list.count()
. Ifobject_list
has nocount()
method, thenPaginator
will fallback to usinglen(object_list)
. This allows objects, such as Django’sQuerySet
, to use a more efficientcount()
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
exceptions
-
exception 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
objects
You 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 usinglen()
or iterating it directly.
Methods
-
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 return3
.
-
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 return4
.
Attributes
-
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/2.0/topics/pagination/