You have to write the custom CheckboxSelectMultiple widget. Using the snippet I have tried make the CheckboxSelectMultiple field iterable by adding the category_name as an attribute in field attrs. So that I can use regroup tag in template later on.
The below code is modified from snippet according to your need, obviously this code can be made more cleaner and more generic, but at this moment its not generic.
forms.py
from django import forms
from django.forms import Widget
from django.forms.widgets import SubWidget
from django.forms.util import flatatt
from django.utils.html import conditional_escape
from django.utils.encoding import StrAndUnicode, force_unicode
from django.utils.safestring import mark_safe
from itertools import chain
import ast
from mysite.models import Widget as wid # your model name is conflicted with django.forms.Widget
from mysite.models import Feature
class CheckboxInput(SubWidget):
"""
An object used by CheckboxRenderer that represents a single
<input type="checkbox">.
"""
def __init__(self, name, value, attrs, choice, index):
self.name, self.value = name, value
self.attrs = attrs
self.choice_value = force_unicode(choice[1])
self.choice_label = force_unicode(choice[2])
self.attrs.update({'cat_name': choice[0]})
self.index = index
def __unicode__(self):
return self.render()
def render(self, name=None, value=None, attrs=None, choices=()):
name = name or self.name
value = value or self.value
attrs = attrs or self.attrs
if 'id' in self.attrs:
label_for=" for="%s_%s"" % (self.attrs['id'], self.index)
else:
label_for=""
choice_label = conditional_escape(force_unicode(self.choice_label))
return mark_safe(u'<label%s>%s %s</label>' % (label_for, self.tag(), choice_label))
def is_checked(self):
return self.choice_value in self.value
def tag(self):
if 'id' in self.attrs:
self.attrs['id'] = '%s_%s' % (self.attrs['id'], self.index)
final_attrs = dict(self.attrs, type="checkbox", name=self.name, value=self.choice_value)
if self.is_checked():
final_attrs['checked'] = 'checked'
return mark_safe(u'<input%s />' % flatatt(final_attrs))
class CheckboxRenderer(StrAndUnicode):
def __init__(self, name, value, attrs, choices):
self.name, self.value, self.attrs = name, value, attrs
self.choices = choices
def __iter__(self):
for i, choice in enumerate(self.choices):
yield CheckboxInput(self.name, self.value, self.attrs.copy(), choice, i)
def __getitem__(self, idx):
choice = self.choices[idx] # Let the IndexError propogate
return CheckboxInput(self.name, self.value, self.attrs.copy(), choice, idx)
def __unicode__(self):
return self.render()
def render(self):
"""Outputs a <ul> for this set of checkbox fields."""
return mark_safe(u'<ul>\n%s\n</ul>' % u'\n'.join([u'<li>%s</li>'
% force_unicode(w) for w in self]))
class CheckboxSelectMultipleIter(forms.CheckboxSelectMultiple):
"""
Checkbox multi select field that enables iteration of each checkbox
Similar to django.forms.widgets.RadioSelect
"""
renderer = CheckboxRenderer
def __init__(self, *args, **kwargs):
# Override the default renderer if we were passed one.
renderer = kwargs.pop('renderer', None)
if renderer:
self.renderer = renderer
super(CheckboxSelectMultipleIter, self).__init__(*args, **kwargs)
def subwidgets(self, name, value, attrs=None, choices=()):
for widget in self.get_renderer(name, value, attrs, choices):
yield widget
def get_renderer(self, name, value, attrs=None, choices=()):
"""Returns an instance of the renderer."""
choices_ = [ast.literal_eval(i[1]).iteritems() for i in self.choices]
choices_ = [(a[1], b[1], c[1]) for a, b, c in choices_]
if value is None: value=""
str_values = set([force_unicode(v) for v in value]) # Normalize to string.
if attrs is None:
attrs = {}
if 'id' not in attrs:
attrs['id'] = name
final_attrs = self.build_attrs(attrs)
choices = list(chain(choices_, choices))
return self.renderer(name, str_values, final_attrs, choices)
def render(self, name, value, attrs=None, choices=()):
return self.get_renderer(name, value, attrs, choices).render()
def id_for_label(self, id_):
if id_:
id_ += '_0'
return id_
class WidgetForm(forms.ModelForm):
features = forms.ModelMultipleChoiceField(
queryset=Feature.objects.all().values('id', 'name', 'category__name'),
widget=CheckboxSelectMultipleIter,
required=False
)
class Meta:
model = wid
Then in template:
{% for field in form %}
{% if field.name == 'features' %}
{% regroup field by attrs.cat_name as list %}
<ul>
{% for el in list %}
<li>{{el.grouper}}
<ul>
{% for e in el.list %}
{{e}} <br />
{% endfor %}
</ul>
</li>
{% endfor %}
</ul>
{% else %}
{{field.label}}: {{field}}
{% endif %}
{% endfor %}
Results:
I added countries name in category table, and cities name in features table so in template I was able to regroup the cities (features) according to country (category)
