How to add additional classes to django form field - css

Question

I've just recently learned about:
Form.error_css_class
Form.required_css_class
Docs: https://docs.djangoproject.com/en/dev/ref/forms/api/#django.forms.Form.error_css_class
So by defining 'error_css_class' and 'required_css_class' in forms
class MyForm(forms.Form):
error_css_class = 'error'
required_css_class = 'required'
name = forms.CharField(...)
I can do:
<div class="field-wrapper {{ form.name.css_classes }}">
...
</div>
This will output:
<div class="field-wrapper required">
...
</div>
However I want to add additional classes to the field, e.g I would like to add 'text name' css class for the "name" field. And reading the docs, I think its possible.
https://docs.djangoproject.com/en/dev/ref/forms/api/#django.forms.BoundField.css_classes
After reading the above I tried to do
self.fields['name'].css_classes('name text')
That doesn't work. I get
'CharField' object has no attribute 'css_classes'
I also tried
name = forms.CharField(css_classes='name text')
TypeError
__init__() got an unexpected keyword argument 'css_classes'
I know I can add extra attr to field widget
self.fields['name'].widget.attrs['class'] = 'name text'
But I want to add css classes to field wrapper.
I could write a custom templatetag... to check field name/type and return appropriate css classes... but if there is something builtin .. I would love to keep my templates clean :-).
Also hardcoding css classes per field is not an option .. as the form fields are dynamic.
Any help will be appreciated.

Answer 1

I figured out how to do it using a custom BoundField
from django.forms import forms
class CustomBoundField(forms.BoundField):
def css_classes(self, extra_classes=None):
# logic for determining css_classes has been omitted
extra_classes = ['name', 'text']
return super(CustomBoundField, self).css_classes(extra_classes=extra_classes)
In my forms, I overide getitem
def __getitem__(self, name):
try:
field = self.fields[name]
except KeyError:
raise KeyError('Key %r not found in Form' % name)
return CustomBoundField(self, field, name)