OverviewΒΆ
Suppose your models.py looks something like this:
class Book(models.Model):
name = models.CharField(max_length=100)
binding = models.CharField(max_length=2, choices=BINDING_CHOICES)
authors = models.ManyToManyField(Author)
genre = models.ForeignKey(Genre)
price = models.DecimalField(max_digits=6, decimal_places=2)
date_published = models.DateField()
(with BINDING_CHOICES, Author and Genre omitted for brevity).
You might want to present a list of Book objects, allowing the user to filter on the various fields. Your views.py would be something like this:
from django.shortcuts import render
from myapp.models import Book
def booklist(request):
books = Book.objects.all()
return render(request, "booklist.html", {'books': books})
and the template is like this:
{% for book in books %}
{# etc #}
{% endfor %}
To add the filters, in views.py add a FilterSet subclass and change the view code as follow:
from django.shortcuts import render
from django_easyfilters import FilterSet
from myapp.models import Book
class BookFilterSet(FilterSet):
fields = [
'binding',
'authors',
'genre',
'price',
]
def booklist(request):
books = Book.objects.all()
booksfilter = BookFilterSet(books, request.GET)
return render(request, "booklist.html", {'books': booksfilter.qs,
'booksfilter': booksfilter})
Notice that the books
item put in the context has been replaced by
bookfilter.qs
, so that the QuerySet passed to the template has filtering
applied to it, as defined by BookFilterSet and the information from the query
string (request.GET).
The booksfilter
item has been added to the context in order for the filters
to be displayed on the template.
Then, in the template, just add {{ booksfilter }}
to the template.
You can also use pagination e.g. using django-pagination:
{% autopaginate books 20 %}
<h2>Filters:</h2>
{{ booksfilter }}
{% paginate %}
<h2>Books found</h2>
{% for book in books %}
{# etc #}
{% endfor %}
The FilterSet
also provides a ‘title’ attribute that can be used to provide
a simple summary of what has been selected so far. It is made up of a comma
separated list of chosen fields. For example, if the user has selected genre
‘Classics’ and binding ‘Hardback’ in the example above, you would get the following:
>>> books = Book.objects.all()
>>> booksfilter = BookFilterSet(books, request.GET)
>>> booksfilter.title
u"Hardback, Classics"
The fields used for the title
attribute, and the order they are used, can be
customised by adding a title_fields
attribute to your FilterSet
:
class BookFilterSet(FilterSet):
fields = [
'binding',
'authors',
'genre',
'price',
]
title_fields = ['genre', 'binding']
Customisation of the filters can be done in various ways - see the FilterSet documentation for how to do this, and the Filters documentation for options that can be specified.