PaginationLink para este cabeçalho
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.
ExemploLink para este cabeçalho
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
Using Paginator in a viewLink para este cabeçalho
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 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 objectsLink para este cabeçalho
The Paginator class has this constructor:
- class Paginator(object_list, per_page, orphans=0, allow_empty_first_page=True)Link para esta definição
Argumentos requeridosLink para este cabeçalho
object_listA list, tuple,
QuerySet, or other sliceable object with acount()or__len__()method. For consistent pagination,QuerySets should be ordered, e.g. with anorder_by()clause or with a defaultorderingon the model.per_pageThe maximum number of items to include on a page, not including orphans (see the
orphansoptional argument below).
Argumentos opcionaisLink para este cabeçalho
orphansUse 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.orphansdefaults to zero, which means pages are never combined and the last page may have one item.allow_empty_first_pageWhether or not the first page is allowed to be empty. If
Falseandobject_listis empty, then anEmptyPageerror will be raised.
MétodosLink para este cabeçalho
- Paginator.page(number)Link para esta definição
Returns a
Pageobject with the given 1-based index. RaisesInvalidPageif the given page number doesn’t exist.
AtributosLink para este cabeçalho
- Paginator.countLink para esta definição
The total number of objects, across all pages.
- Paginator.num_pagesLink para esta definição
The total number of pages.
- Paginator.page_rangeLink para esta definição
A 1-based range iterator of page numbers, e.g. yielding
[1, 2, 3, 4].
InvalidPage exceptionsLink para este cabeçalho
- exception InvalidPageLink para esta definição
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 PageNotAnIntegerLink para esta definição
Raised when
page()is given a value that isn’t an integer.
- exception EmptyPageLink para esta definição
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 objectsLink para este cabeçalho
You usually won’t construct Page objects by hand – you’ll get them
using Paginator.page().
- class Page(object_list, number, paginator)Link para esta definição
A page acts like a sequence of
Page.object_listwhen usinglen()or iterating it directly.
MétodosLink para este cabeçalho
- Page.has_next()Link para esta definição
Returns
Trueif there’s a next page.
- Page.has_previous()Link para esta definição
Returns
Trueif there’s a previous page.
- Page.has_other_pages()Link para esta definição
Returns
Trueif there’s a next or previous page.
- Page.next_page_number()Link para esta definição
Returns the next page number. Raises
InvalidPageif next page doesn’t exist.
- Page.previous_page_number()Link para esta definição
Returns the previous page number. Raises
InvalidPageif previous page doesn’t exist.
- Page.start_index()Link para esta definição
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()Link para esta definição
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.
AtributosLink para este cabeçalho
- Page.object_listLink para esta definição
The list of objects on this page.
- Page.numberLink para esta definição
The 1-based page number for this page.
- Page.paginatorLink para esta definição
The associated
Paginatorobject.