How to provide Django label_tag and as_widget arguments (e.g. contents and attrs)

Question

From django/forms/forms.py:

def label_tag(self, contents=None, attrs=None):
    ..

def as_widget(self, widget=None, attrs=None, only_initial=False):
    ..

From my templates I call the label_tag as follows:

{{ form.my_field.label_tag }}

which outputs the label.

How should I provide the arguments to those tag as in their definition? For example I want to provide an alternative label text and css classes.

I tried something like:

{{ form.my_field.label_tag contents='My alternative label' }}

but it gives me:

Could not parse the remainder: ' contents='My alternative label'' from 'form.code.label_tag contents='My alternative label''

The same goes for the attrs field. Can I supply a value for that one from the template. I would like to provide the css class. For css class I'm using a filter at the moment but while going through the Django source code I noticed label_tag and as_widget has these additional arguments, and that's why I'm wondering now I can supply them from my templates.

(I'm using Django 1.4 on App Engine)

Answer 1

Django very deliberately limits template functionality to ensure you don't end up writing the whole website in the template as you might with PHP.

From the The Django Book 2.0: Templates: Philosophies and Limitations :

...it's impossible to call Python code directly within Django templates. All “programming” is fundamentally limited to the scope of what template tags can do.

You could write a custom template tag or filter that does what you want... but — as this seems to be form logic — you would almost certainly be better off doing something else.

Simplest might be to define the label/widget where the form is defined. ie:

from django import forms

class MyForm(forms.Form):
    my_field = forms.CharField(label='My label', widget=forms.Textarea)

That said, for the widget, there are other documented ways . If you use django-floppy-forms you can easily override the whole template used to render them.

Finally, I highly recommend django-crispyforms . It saves you a lot of time because you no longer have the pain of hand-writing forms in templates.