Django-crispy-forms - Miguel Araujo¶

Tags: django, pygrunn

django-crispy-forms is a Django application, but Miguel thinks the talk will help you also with designing other systems and applications.

Django has three ways to render forms: as_ul, as_p, as_table. They do the same, but render themselves in a different way. Common questions by people new to Django is “what about divs?” and “how to reorder fields?”. For the last one, you need to switch the order of the form fields in your python form code. There are some other tricks like overriding the self.fields.keyOrder attribute. If you have many fields, regular list methods like delete() and pop() and insert() might help you.

But… ModelForms for the admin interface are different again: the abovementioned form tricks don’t work there. And those tricks sound a bit dirty anyway. So: how to customize the form output?

You can do a lot in by customizing the Django form in the template, but most of it will be hardcoded and hand-tweaked that way. And if you customize a form, you’ll often forget form.errors and form.non_field_errors, for instance.

Django-crispy-forms was formerly known as django-uni-forms. It was created by pydanny in 2008, Miguel is now one of the main committers.

Crispy forms work on forms, modelforms and on formsets. A |crispy filter in the template renders your form as handy divs with better classes and IDs which helps a lot if you want to customize your form with css. Neat!

Crispy also has a {% crispy %} template tag. You can pass it a “form helper”. A form helper is a global helper: it is decoupled from forms. So it normally works with any form. There are some attributes on the form helper that you can set, like method (get/post), form_id, things like that.

You can customize such a helper specifically for one form and set the order of the fields, for instance. There are so many things you might want to customize; crispy supports/allows most/all of them with a Layout class and other layout classes like Div. You can get really deep into the machinery by letting crispy inject Django template code directly into the template…

For the ultimate in customizability, you can write your own layout class that renders itself in whatever way you want. Layouts can be nested, so there is a lot of flexibility here. You can also customize crispy’s own templates that it uses for fields and forms using the regular Django overwrite-a-template mechanism.

Handy: crispy forms has specific support for twitter bootstrap. This helps you get a nice looking form.