This is an improvement of snippet 253 in that it supports database queries.
Implementing autocompletion for foreign keys takes a few steps:
1) Put the snippet above into <app>/widgets/autocomplete.py.
2) Create a view of your foreign key model (here: Donator) in <app>/donator/views.py:
from models import Donator
from widgets.autocomplete import autocomplete_response
def autocomplete(request):
return autocomplete_response(
request.REQUEST['text'], Donator, (
'line_1', 'line_2', 'line_3', 'line_4',
'line_5', 'line_6', 'line_7', 'line_8',
'^zip_code', 'location'
)
)
This view returns the autocompletion result by searching the fields in the tuple. Each word from the form field must appear at least in one database field.
3) Create a URLconf that points to this new view.
4) In the form where you need the autocompletion, define the widget of the foreign key field as an instance of AutoCompleteField:
from widget.autocomplete import AutoCompleteField
field.widget = AutoCompleteField(
url='/donator/autocomplete/'),
options={'minChars': 3}
)
The url parameter is the URL connected to the view in step 3), the options dict is passed on to the Ajax.Autocompleter JavaScript object.
Links:
* [Snippet 253](http://www.djangosnippets.org/snippets/253/)
* [Django and scriptaculous integration](http://wiki.script.aculo.us/scriptaculous/show/IntegrationWithDjango)
* [Ajax.Autocompleter](http://wiki.script.aculo.us/scriptaculous/show/Ajax.Autocompleter)
- ajax
- selection
- database
- autocomplete
- query
- foreign-key
- prototype
- scriptaculous
- protoculous
This middleware remembers the last URLs that the user visited on your Django-site and saves them into the `request.session`.
The fields are `currently_visiting` for the URL that is opened by the user and `last_visited` which is the URL before. Most of the time, you'll need only `last_visited`, as `currently_visiting` is just an implementation detail.
For what is this good for? Imagine, you have to implement something like JavaScripts `history.back()` or `history.forward(-1)` but without JavaScript. Things start to get difficult when using JavaScript is not possible, for whatever reason.
This snippet was created because I needed to redirect the user to the page he's been watching before clicking on the "translate" link. One other alternative would be adding the URL the user was visiting as a GET field to the "translate" link, but I hoped to find a possibility to avoid GET.
This snippet works quite well as a proof of concept, the only known wart is when the user uses tabs or multible windows on the site, things get messed up. This cannot be solved, it's a restriction imposed by the design of HTTP.
You may want to access to "global" errors in your template, typically when you have a custom `clean()` method which checks several fields. `{{ form.errors }}` gives an < ul >, which is often not what you want, and `{{ form.errors|join:", " }}` iterates in the keys of `errors` (which are the names of fields, uninteresting).
The global `errors`'s key is "__all__", and Django doesn't allow us to do `{{ form.errors.__all__ }}`.
This method returns an array, like a classic `{{ form.field.errors }}`, and can be used with a join : `{{ form.get_global_errors|join:", " }}`.