Copy-edited docs from [303] and [304]

git-svn-id: http://code.djangoproject.com/svn/django/trunk@306 bcc190cf-cafb-0310-a4f2-bffc1f526a37
This commit is contained in:
Adrian Holovaty 2005-07-25 17:18:39 +00:00
parent 1c947e50c9
commit f6c4395329
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@ -4,18 +4,18 @@ Forms, fields, and manipulators
Once you've got a chance to play with Django's admin interface, you'll probably
wonder if the fantastic form validation framework it uses is available to user
code. It is, and this document explains how the framework works.
code. It is, and this document explains how the framework works.
.. admonition:: A note to the lazy
If all you want to do is present forms for a user to create and/or
update a given object, don't read any further but instead click thyself
over to the `generic views`_ documentation. The following exercises are
update a given object, don't read any further. Instead, click thyself
to the `generic views`_ documentation. The following exercises are
for those interested in how Django's form framework works and those
needing to do more than simple create/update.
needing to do more than simple creation/updating.
We'll take a top-down approach to examining Django's form validation framework
since much of the time you won't need to use the lower-level APIs. Throughout
We'll take a top-down approach to examining Django's form validation framework,
becuase much of the time you won't need to use the lower-level APIs. Throughout
this document, we'll be working with the following model, a "place" object::
PLACE_TYPES = (
@ -27,12 +27,12 @@ this document, we'll be working with the following model, a "place" object::
class Place(meta.Model):
fields = (
meta.CharField('name', 'name', maxlength=100),
meta.CharField('address', 'address', maxlength=100, blank=True),
meta.CharField('city', 'city', maxlength=50, blank=True),
meta.USStateField('state', 'state'),
meta.CharField('zip_code', 'zip code', maxlength=5, blank=True),
meta.IntegerField('place_type', 'place type', choices=PLACE_TYPES)
meta.CharField('name', maxlength=100),
meta.CharField('address', maxlength=100, blank=True),
meta.CharField('city', maxlength=50, blank=True),
meta.USStateField('state'),
meta.CharField('zip_code', maxlength=5, blank=True),
meta.IntegerField('place_type', choices=PLACE_TYPES)
)
def __repr__(self):
@ -47,8 +47,8 @@ Manipulators
The highest-level interface for object creation and modification is the
**Manipulator** framework. A manipulator is a utility class tied to a given
model that "knows" how to create or modify instances of that model and how to
validate data for the object. Manipulators come in two flavors:
``AddManipulators`` and ``ChangeManipulators``. Functionally they are quite
validate data for the object. Manipulators come in two flavors:
``AddManipulators`` and ``ChangeManipulators``. Functionally they are quite
similar, but the former knows how to create new instances of the model, while
the later modifies existing instances. Both types of classes are automatically
created when you define a new class::
@ -74,55 +74,57 @@ POSTed data from the browser and creates a new ``Place`` object::
def naive_create_place(request):
"""A naive approach to creating places; don't actually use this!"""
# Create the AddManipulator
# Create the AddManipulator.
manipulator = places.AddManipulator()
# Make a copy of the POSTed data so that do_html2python can
# modify it in place (request.POST is immutable)
# modify it in place (request.POST is immutable).
new_data = request.POST.copy()
# Convert the request data (which will all be strings) into the
# appropriate Python types for those fields
# appropriate Python types for those fields.
manipulator.do_html2python(new_data)
# Save the new object
# Save the new object.
new_place = manipulator.save(new_data)
# It worked!
return HttpResponse("Place created: %s" % new_place)
The ``naive_create_place`` example works (somewhat), but as you probably can
tell, there's all sorts of problems (some more subtle than others) with this view:
The ``naive_create_place`` example works, but as you probably can tell, this
view has a number of problems:
* No validation of any sort is performed; if, for example, the ``name`` field
* No validation of any sort is performed. If, for example, the ``name`` field
isn't given in ``request.POST``, the save step will cause a database error
because that field is required. Ugly.
because that field is required. Ugly.
* Even if you *do* perform validation, there's still no way to give that information
to the user is any sort of useful way.
* Even if you *do* perform validation, there's still no way to give that
information to the user is any sort of useful way.
* You'll have to separate create a form (and view) that submits to this page, which is
a pain and is redundant.
* You'll have to separate create a form (and view) that submits to this
page, which is a pain and is redundant.
Let's dodge these problems momentarily to take a look at how you could create a
view with a form that submits to this flawed creation view::
def naive_create_place_form(request):
"""Simplistic place form view; don't actually use anything like this!"""
# Create a FormWrapper object which the template can use; more
# on what the second two arguments to FormWrapper do later.
# Create a FormWrapper object that the template can use. Ignore
# the last two arguments to FormWrapper for now.
form = formfields.FormWrapper(places.AddManipulator(), {}, {})
# Create a template, context, and response
# Create a template, context and response.
t = template_loader.get_template('places/naive_create_form')
c = Context(request, {'form' : form})
c = Context(request, {
'form': form
})
return HttpResponse(t.render(c))
(This view, as well as all the following ones, have the same imports as the
first example above does.)
(This view, as well as all the following ones, has the same imports as in the
first example above.)
The ``formfields.FormWrapper`` object is a wrapper that templates can
easily deal with to create forms; here's the ``naive_create_form`` template::
easily deal with to create forms. Here's the ``naive_create_form`` template::
{% extends "base" %}
@ -147,18 +149,18 @@ some salient points of the above template::
creates the "right" type of widget for the form, as you can see with the
``place_type`` field above.
* There isn't a way just to spit out the form; you'll still need to define
how the form gets laid out. This is a feature: every form needs to be
designed differently; Django doesn't force you into any type of mould.
If you must use tables, use tables; if you're a semantic purist you can
probably find better HTML than the above template.
* There isn't a way just to spit out the form. You'll still need to define
how the form gets laid out. This is a feature: Every form should be
designed differently. Django doesn't force you into any type of mold.
If you must use tables, use tables. If you're a semantic purist, you can
probably find better HTML than in the above template.
* To avoid name conflicts, the ``id``s of form elements take the form
"id_*fieldname*".
By creating a creation form we've solved problem number 3 above, but we still don't
have any validation; if you enter bad data into any of the . Let's revise the validation
issue by writing a new creation view that takes into account validation::
By creating a creation form we've solved problem number 3 above, but we still
don't have any validation. Let's revise the validation issue by writing a new
creation view that takes validation into account::
def create_place_with_validation(request):
manipulator = places.AddManipulator()
@ -168,7 +170,9 @@ issue by writing a new creation view that takes into account validation::
errors = manipulator.get_validation_errors(new_data)
if errors:
t = template_loader.get_template('places/errors')
c = Context(request, {'errors' : errors}
c = Context(request, {
'errors': errors
}
return HttpResponse(t.render(c))
else:
manipulator.do_html2python(request.POST)
@ -192,25 +196,26 @@ on an error page (templated, of course)::
{% endblock %}
Still, this now has its own problems:
Still, this has its own problems:
* There's still the issue of creating a seperate (redundant) view for the
* There's still the issue of creating a separate (redundant) view for the
submission form.
* Errors, though nicely presented are on a seperate page, so the user will have
to use the "back" button to fix errors -- not exactly usable!
* Errors, though nicely presented, are on a separate page, so the user will
have to use the "back" button to fix errors. That's ridiculous and unusable.
The best way to deal with these issues is to collapse the two views -- the form and the
submission -- into a single view. This view will be responsible for creating the
form, validating POSTed data, and creating the new object (should it the data be
valid). An added bonus of this approach is that errors and the form will both
be available on the same page, so errors with fields can be presented in context.
The best way to deal with these issues is to collapse the two views -- the form
and the submission -- into a single view. This view will be responsible for
creating the form, validating POSTed data, and creating the new object (if the
data is valid). An added bonus of this approach is that errors and the form will
both be available on the same page, so errors with fields can be presented in
context.
.. admonition:: Philosophy::
Finally, for the HTTP purists in the audience (and the authorship), this
nicely matches the "true" meanings of HTTP-GET and HTTP-POST: GET fetches
the form, POST creates the new object.
nicely matches the "true" meanings of HTTP GET and HTTP POST: GET fetches
the form, and POST creates the new object.
Below is the finished view::
@ -218,29 +223,31 @@ Below is the finished view::
manipulator = places.AddManipulator()
if request.POST:
# If data was POSTed, we're trying to create a new Place
# If data was POSTed, we're trying to create a new Place.
new_data = request.POST.copy()
# Check for errors
# Check for errors.
errors = manipulator.get_validation_errors(new_data)
if not errors:
# No errors -- this means we can save the data!
# No errors. This means we can save the data!
manipulator.do_html2python(new_data)
new_place = manipulator.save(new_data)
# Redirect to the object's "edit" page (so that reloads
# don't accidentally create duplicate entries)
# Redirect to the object's "edit" page. Always use a redirect
# after POST data, so that reloads don't accidently create
# duplicate entires, and so users don't see the confusing
# "Repost POST data?" alert box in their browsers.
return HttpResponseRedirect("/places/edit/%i/" % new_place.id)
else:
# No POST, so we want a brand new form without any data or errors
# No POST, so we want a brand new form without any data or errors.
errors = new_data = {}
# Create the FormWrapper, template, context, response
# Create the FormWrapper, template, context, response.
form = formfields.FormWrapper(manipulator, new_data, errors)
t = template_loader.get_template("places/create_form")
c = Context(request, {
'form' : form,
'form': form,
})
return HttpResponse(t.render(c))
@ -287,34 +294,33 @@ and here's the ``create_form`` template::
The second two arguments to ``FormWrapper`` (``new_data`` and ``errors``)
deserve some mention.
The first is any "default" data to be used as values for the fields; pulling the
data from ``request.POST`` as is done above makes sure that if there are errors,
the values the user put in aren't lost. If you try the above example, you'll see
this in action.
The first is any "default" data to be used as values for the fields. Pulling
the data from ``request.POST``, as is done above, makes sure that if there are
errors, the values the user put in aren't lost. If you try the above example,
you'll see this in action.
The second argument is the error list retrieved from
``manipulator.get_validation_errors``. When passed into the ``FormWrapper``, this gives
each field an ``errors`` item (which is a list of error messages associated with the
field) as well as a ``html_error_list`` item which is a ``<ul>`` of error messages.
The above template uses these error items to display a simple error message next
to each field.
``manipulator.get_validation_errors``. When passed into the ``FormWrapper``,
this gives each field an ``errors`` item (which is a list of error messages
associated with the field) as well as a ``html_error_list`` item, which is a
``<ul>`` of error messages. The above template uses these error items to
display a simple error message next to each field.
Using the ``ChangeManipulator``
-------------------------------
So: the above has covered using the ``AddManipulator`` to create a new object;
what about editing an existing one? It's rather shockingly similar to creating
a new one::
The above has covered using the ``AddManipulator`` to create a new object. What
about editing an existing one? It's shockingly similar to creating a new one::
def edit_place(request, place_id):
# Get the place in question from the database and create a ChangeManipulator
# at the same time
# Get the place in question from the database and create a
# ChangeManipulator at the same time.
try:
manipulator = places.ChangeManipulator(place_id)
except places.PlaceDoesNotExist:
raise Http404
# Grab the Place object is question for future use
# Grab the Place object is question for future use.
place = manipulator.original_object
if request.POST:
@ -334,46 +340,46 @@ a new one::
form = formfields.FormWrapper(manipulator, new_data, errors)
t = template_loader.get_template("places/edit_form")
c = Context(request, {
'form' : form,
'place' : place,
'form': form,
'place': place,
})
return HttpResponse(t.render(c))
The only real differences here are:
The only real differences are:
* A ``ChangeManipulator`` instead of an ``AddManipulator`` is created;
The argument to any ``ChangeManipulator`` is the id of the object
to be changed. As you can see, the initializer will raise an
``ObjectDoesNotExist`` exception if the id is invalid.
* We create a ``ChangeManipulator`` instead of an ``AddManipulator``.
The argument to a ``ChangeManipulator`` is the ID of the object
to be changed. As you can see, the initializer will raise an
``ObjectDoesNotExist`` exception if the ID is invalid.
* ``ChangeManipulator.original_object`` stores the instance of the
object being edited.
* We set ``new_data`` to the original object's ``__dict__``; this makes
sure that the form fields contain the current values of the object.
* We set ``new_data`` to the original object's ``__dict__``. This makes
sure the form fields contain the current values of the object.
``FormWrapper`` does not modify ``new_data`` in any way, and templates
cannot, so this is perfectly safe.
* The above example uses a different template so that create and edit can
be "skinned" differently if needed, but the form chunk itself is
completely identical to the one in the create form above.
* The above example uses a different template, so create and edit can be
"skinned" differently if needed, but the form chunk itself is completely
identical to the one in the create form above.
The astute programmer will notice that the add and create functions are nearly
identical and could in fact be collapsed into a single view; this is left
as an exercise for said programmer.
The astute programmer will notice the add and create functions are nearly
identical and could in fact be collapsed into a single view. This is left as an
exercise for said programmer.
(However, the even-more-astute programmer will take heed of the note at the top
of this document and check out the `generic views`_ documentation if all she
wishes to do is this type of simple create/update).
wishes to do is this type of simple create/update.)
Custom forms and manipulators
=============================
All the above is fine and dandy if you want to just use the automatically created
manipulators, but the coolness doesn't end there: you can easily create your
own custom manipulators for handling custom forms.
All the above is fine and dandy if you just want to use the automatically
created manipulators. But the coolness doesn't end there: You can easily create
your own custom manipulators for handling custom forms.
Custom manipulators are pretty simple; here's a manipulator that you might use
Custom manipulators are pretty simple. Here's a manipulator that you might use
for a "contact" form on a website::
from django.core import formfields
@ -394,13 +400,13 @@ for a "contact" form on a website::
formfields.LargeTextField(field_name="contents", is_required=True),
)
A certain similarity to Django's models should be apparent. The only required
A certain similarity to Django's models should be apparent. The only required
method of a custom manipulator is ``__init__`` which must define the fields
present in the manipulator. See the ``django.core.formfields`` module for
all the form fields provided by Django.
You use this custom manipulator exactly as you would use an auto-generated one;
here's a simple function that might drive the above form::
You use this custom manipulator exactly as you would use an auto-generated one.
Here's a simple function that might drive the above form::
def contact_form(request):
manipulator = ContactFormManipulator()
@ -410,7 +416,7 @@ here's a simple function that might drive the above form::
if not errors:
manipulator.do_html2python(new_data)
# send email using new_data here...
# Send e-mail using new_data here...
return HttpResponseRedirect("/contact/thankyou/")
else:
@ -418,18 +424,18 @@ here's a simple function that might drive the above form::
form = formfields.FormWrapper(manipulator, new_data, errors)
t = template_loader.get_template("contact_form")
c = Context(request, {
'form' : form,
'form': form,
})
return HttpResponse(t.render(c))
Validators
==========
One extremely useful feature of manipulators is the automatic validation it
performs. Validation is done using a simple validation API: a validator is
simple a callable that raises a ``ValidationError`` if there's something wrong
with the data. ``django.core.validators`` defines a whole host of validator
functions, but defining your own couldn't be easier::
One useful feature of manipulators is the automatic validation. Validation is
done using a simple validation API: A validator is a callable that raises a
``ValidationError`` if there's something wrong with the data.
``django.core.validators`` defines a host of validator functions, but defining
your own couldn't be easier::
from django.core import validators, formfields
@ -442,15 +448,18 @@ functions, but defining your own couldn't be easier::
def isValidToAddress(self, field_data, all_data):
if not field_data.endswith("@example.com"):
raise ValidationError("You can only send messages to example.com email addresses")
raise ValidationError("You can only send messages to example.com e-mail addresses.")
Above, we've added a "to" field to the contact form, but required that the
"to" address end with "@example.com" by adding the ``isValidToAddress``
validator to the field's ``validator_list``.
Above, we've added a "to" field to the contact form, but required that the "to"
address end with "@example.com" by adding the ``isValidToAddress`` validator to
the field's ``validator_list``.
The arguments to a validator function take a little explanation. ``field_data``
is the value of the field in question, and ``all_data`` is a dict of all the
data being validated. Note that at the point validators are called all data
will still be strings (as ``do_html2python`` hasn't been called yet).
is the value of the field in question, and ``all_data`` is a dictionary of all
the data being validated. Note that at the point validators are called all
data will still be strings (as ``do_html2python`` hasn't been called yet).
Also, because consistency in user interfaces is important, we strongly urge you
to put punctuation at the end of your validation messages.
.. _`generic views`: http://www.djangoproject.com/documentation/generic_views/

View File

@ -2,10 +2,10 @@
Using generic views
===================
Writing web applications can often be monotonous as we repeat certain patterns
again and again. In Django, the most common of these patterns have been abstracted into
"generic views" that let you quickly provide common views of object without actually
needing to write any views.
Writing Web applications can be monotonous, because we repeat certain patterns
again and again. In Django, the most common of these patterns have been
abstracted into "generic views" that let you quickly provide common views of
an object without actually needing to write any views.
Django's generic views contain the following:
@ -26,17 +26,17 @@ Django's generic views contain the following:
.. _detail: http://www.djangoproject.com/weblog/2005/jul/20/autoreload/
.. _latest: http://www.djangoproject.com/weblog/
All of these views are used by creating configuration dictionaries in
your urlconfig files and passing those dicts as the third member of the
urlconf tuple. For example, here's the urlconf for the simple weblog
app that drives the blog on djangoproject.com::
All of these views are used by creating configuration dictionaries in
your URLconf files and passing those dictionaries as the third member of the
URLconf tuple. For example, here's the URLconf for the simple weblog app that
drives the blog on djangoproject.com::
from django.conf.urls.defaults import *
info_dict = {
'app_label': 'blog',
'app_label': 'blog',
'module_name': 'entries',
'date_field': 'pub_date',
'date_field': 'pub_date',
}
urlpatterns = patterns('django.views.generic.date_based',
@ -47,48 +47,50 @@ app that drives the blog on djangoproject.com::
(r'^/?$', 'archive_index', info_dict),
)
As you can see, this urlconf defines a few options in ``info_dict`` that tell
As you can see, this URLconf defines a few options in ``info_dict`` that tell
the generic view which model to use (``blog.entries`` in this case), as well as
some extra information.
Documentation of each generic view follows along with a list of all keyword arguments
that a generic view expects. Remember that as in the example above, arguments may
either come from the URL pattern (as ``month``, ``day``, ``year``, etc. do above) or
from the additional information dict (as for ``app_label``, ``module_name``, etc.).
Documentation of each generic view follows, along with a list of all keyword
arguments that a generic view expects. Remember that as in the example above,
arguments may either come from the URL pattern (as ``month``, ``day``,
``year``, etc. do above) or from the additional-information dictionary (as for
``app_label``, ``module_name``, etc.).
All the generic views that follow require the ``app_label`` and ``module_name`` keys.
These values are easiest to explain through example::
>>> from django.models.blog import entries
In the above line, ``blog`` is the ``app_label`` (this is the name of the file that
holds all your model definitions) and ``entries`` is the ``module_name`` (this is
either a pluralized, lowercased version of the model class name or the value of
the ``module_name`` option of your model). In the docs below, these keys will not
be repeated, but each generic view requires them.
In the above line, ``blog`` is the ``app_label`` (the name of the file that
holds all your model definitions) and ``entries`` is the ``module_name``
(either a pluralized, lowercased version of the model class name, or the value
of the ``module_name`` option of your model). In the docs below, these keys
will not be repeated, but each generic view requires them.
Using date-based generic views
==============================
Date-based generic views (in the module ``django.views.generic.date_based``)
export six functions for dealing with date-based data. Besides ``app_label``
and ``module_name``, all date-based generic views require that the ``date_field``
argument to passed to them; this is the name of the field that stores the date
the objects should key off of.
feature six functions for dealing with date-based data. Besides ``app_label``
and ``module_name``, all date-based generic views require that the
``date_field`` argument be passed to them. This is the name of the field that
stores the date the objects should key off of.
Additional, all date-based generic views have the following optional arguments:
Additionally, all date-based generic views have the following optional
arguments:
======================= ==================================================
Argument Description
======================= ==================================================
``template_name`` Override the default template name used for the
``template_name`` Overrides the default template name used for the
view.
``extra_lookup_kwargs`` A dictionary of extra lookup parameters (see
the `database API docs`_).
``extra_context`` A dict of extra data to put into the template's
context.
``extra_context`` A dictionary of extra data to put into the
template's context.
======================= ==================================================
.. _`database API docs`: http://www.djangoproject.com/documentation/db_api/
@ -96,9 +98,9 @@ Additional, all date-based generic views have the following optional arguments:
The date-based generic functions are:
``archive_index``
A top-level index page showing the "latest" objects. Has an optional argument,
``num_latest`` which is the number of items to display on the page (defaults
to 15).
A top-level index page showing the "latest" objects. Has an optional
argument, ``num_latest``, which is the number of items to display on the
page (defaults to 15).
Uses the template ``app_label/module_name_archive`` by default.
@ -110,7 +112,7 @@ The date-based generic functions are:
Latest objects by date
``archive_year``
Yearly archive. Requires that the ``year`` argument be present in the URL
Yearly archive. Requires that the ``year`` argument be present in the URL
pattern.
Uses the template ``app_label/module_name__archive_year`` by default.
@ -118,56 +120,56 @@ The date-based generic functions are:
Has the following template context:
``date_list``
List of months in this year with objects
List of months in the given year with objects
``year``
This year
The given year (an integer)
``archive_month``
Monthly archive; requires that ``year`` and ``month`` arguments be given.
Monthly archive. Requires that ``year`` and ``month`` arguments be given.
Uses the template ``app_label/module_name__archive_month`` by default.
Has the following template context:
``month``
(datetime object) this month
The given month (a datetime.datetime object)
``object_list``
list of objects published in the given month
List of objects published in the given month
``archive_day``
Daily archive; requires that ``year``, ``month``, and ``day`` arguments
be given.
Daily archive. Requires that ``year``, ``month``, and ``day`` arguments be
given.
Uses the template ``app_label/module_name__archive_day`` by default.
Has the following template context:
``object_list``
list of objects published this day
List of objects published this day
``day``
(datetime) the day
The given day (a datetime.datetime object)
``previous_day``
(datetime) the previous day
The previous day (a datetime.datetime object)
``next_day``
(datetime) the next day, or None if the current day is today
The next day (a datetime.datetime object), or None if the given
day is today
``archive_today``
List of objects for today; exactly the same as ``archive_day``, except
that the year/month/day arguments are not given and today's date is
used instead.
List of objects for today. Exactly the same as ``archive_day``, except
the year/month/day arguments are not given, and today's date is used
instead.
``object_detail``
Individual object page; requires ``year``/``month``/``day`` arguments like
``archive_day``. This function can be used with two types of URLs: either
Individual object page. Requires ``year``/``month``/``day`` arguments like
``archive_day``. This function can be used with two types of URLs: either
``/year/month/day/slug/`` or ``/year/month/day/object_id/``.
If you're using the slug-style URLs, you'll need to have a ``slug`` item in
your urlconf, and you'll need to pass a ``slug_field`` key in your info
dict to indicate the name of the slug field.
your URLconf, and you'll need to pass a ``slug_field`` key in your info
dictionary to indicate the name of the slug field.
If your using the object_id-style URLs, you'll just need to have the URL
pattern have an ``object_id`` field.
If your using the object_id-style URLs, you'll just need to give the URL
pattern an ``object_id`` field.
You can also pass the ``template_name_field`` argument to indicate that the
the object stores the name of its template in a field on the object itself.
@ -175,11 +177,11 @@ The date-based generic functions are:
Using list/detail generic views
===============================
The list-detail generic views (in the ``django.views.generic.list_detail`` module)
are similar to the data-based ones, except the list-detail views simply have two
views: a list of objects, and an individual object page.
The list-detail generic views (in the ``django.views.generic.list_detail``
module) are similar to the data-based ones, except the list-detail views simply
have two views: a list of objects, and an individual object page.
All these views take the same three optional arguments as the date-based ones do
All these views take the same three optional arguments as the date-based ones
(and they obviously do not accept or require the date field argument).
Individual views are:
@ -197,9 +199,9 @@ Individual views are:
The view will expect a ``page`` GET param with
the (zero-indexed) page number.
``allow_empty`` If ``False`` and there are no objects to display
``allow_empty`` If ``False`` and there are no objects to display,
the view will raise a 404 instead of displaying
an empty index page.
an empty index page. ``False`` is default.
======================= =================================================
Uses the template ``app_label/module_name__list`` by default.
@ -207,60 +209,61 @@ Individual views are:
Has the following template context:
``object_list``
list of objects
List of objects
``is_paginated``
are the results paginated?
Are the results paginated? Either True or False
If the results are paginated, the context will have some extra variables:
``results_per_page``
number of objects per page
Number of objects per page
``has_next``
is there a next page?
Is there a next page?
``has_previous``
is there a prev page?
Is there a previous page?
``page``
the current page
The current page number
``next``
the next page
The next page number
``previous``
the previous page
The previous page
``pages``
number of pages, total
Number of pages total
``object_detail``
Object detail page. This works like and takes the same arguments as
the date-based ``object_detail`` above, except this one obviously
Object detail page. This works like and takes the same arguments as
the date-based ``object_detail`` above, except this one, obviously,
does not take the year/month/day arguments.
Using create/update/delete generic views
========================================
The ``django.views.generic.create_update`` module contains a set of functions
for creating, editing, and deleting objects. These views take the same global
arguments as the above sets of generic views; they also have a
for creating, editing and deleting objects. These views take the same global
arguments as the above sets of generic views. They also have a
``login_required`` argument which, if ``True``, requires the user to be logged
in to have access to the page (``login_required`` defaults to ``False``).
in to have access to the page. (``login_required`` defaults to ``False``.)
The create/update/delete views are:
``create_object``
Create a new object. Has an extra optional argument, ``post_save_redirect``,
which is a URL that the view will redirect to after saving the object
(defaults to ``object.get_absolute_url()``).
Create a new object. Has an extra optional argument, ``post_save_redirect``,
which is a URL to which the view will redirect after saving the object.
It defaults to ``object.get_absolute_url()``.
``post_save_redirect`` may contain dictionary string formatting which will
be interpolated against the object's dict (so you could use
``post_save_redirect="/polls/%(slug)s/"``, for example).
``post_save_redirect`` may contain dictionary string formatting, which will
be interpolated against the object's field attributes. For example, you
could use ``post_save_redirect="/polls/%(slug)s/"``.
Uses the template ``app_label/module_name__form`` by default (this is the
same template as the ``update_object`` view below; your template can tell
the different by the presence or absence of ``{{ object }}`` in the context.
Uses the template ``app_label/module_name__form`` by default. This is the
same template as the ``update_object`` view below. Your template can tell
the different by the presence or absence of ``{{ object }}`` in the
context.
Has the following template context:
form
the form wrapper for the object
The form wrapper for the object
.. admonition:: Note
@ -270,32 +273,33 @@ The create/update/delete views are:
.. _`manipulator and formfield documentation`: http://www.djangoproject.com/documentation/forms/
``update_object``
Edit an existing object. Has the same extra slug/ID parameters as
``list_detail.object_detail`` does (see above), and the same ``post_save_redirect``
as ``create_object`` does.
Edit an existing object. Has the same extra slug/ID parameters as
``list_detail.object_detail`` does (see above), and the same
``post_save_redirect`` as ``create_object`` does.
Uses the template ``app_label/module_name__form`` by default.
Has the following template context:
form
the form wrapper for the object
The form wrapper for the object
object
the original object being edited
The original object being edited
``delete_object``
Delete an existing object. The given object will only actually be deleted if
the request method is POST; if this view is fetched with GET it will display
a confirmation page that should contain a form that POSTs to the same URL.
Delete an existing object. The given object will only actually be deleted
if the request method is POST. If this view is fetched with GET, it will
display a confirmation page that should contain a form that POSTs to the
same URL.
You must provide the ``post_delete_redirect`` argument to this function so
You must provide the ``post_delete_redirect`` argument to this function, so
that the view knows where to go after the object is deleted.
If fetched with GET, uses the template
``app_label/module_name_s_confirm_delete`` by default (uses no template if
POSTed; simply deletes the object).
If fetched with GET, it uses the template
``app_label/module_name_s_confirm_delete`` by default. It uses no template
if POSTed -- it simply deletes the object and redirects.
Has the following template context:
object
the object about to be deleted
The object about to be deleted