# File: filterspecs.py
from django.db import models
from django.contrib.admin.util import get_model_from_relation
from django.contrib.admin.filterspecs import FilterSpec
from django.utils.translation import ugettext as _
class OneToOneExistsFilterSpec(FilterSpec):
def __init__(self, f, request, params, model, model_admin,
field_path=None):
super(OneToOneExistsFilterSpec, self).__init__(f, request, params,
model, model_admin,
field_path=field_path)
other_model = get_model_from_relation(f)
if isinstance(f, (models.ManyToManyField,
models.related.RelatedObject)):
# no direct field on this model, get name from other model
self.lookup_title = other_model._meta.verbose_name
else:
self.lookup_title = f.verbose_name # use field name
self.lookup_kwarg = '%s__isnull' % self.field_path
self.lookup_val = request.GET.get(self.lookup_kwarg, None)
def title(self):
return self.lookup_title
def choices(self, cl):
for k, v in ((_('All'), None), (_('Yes'), 'False'), (_('No'), 'True')):
yield {'selected': self.lookup_val == v,
'query_string': cl.get_query_string(
{self.lookup_kwarg: v},
[self.lookup_kwarg]),
'display': k}
# registering the filter
FilterSpec.filter_specs.insert(0, (lambda f: getattr(f.field, 'exists_filter', False),
OneToOneExistsFilterSpec))
Comments
The register portion does not work correctly for all field types, try this:
django.contrib.admin.filterspecs.FilterSpec.filter_specs.insert( 0, (lambda f: (hasattr(f, 'field') and getattr(f.field, 'exists_filter', False)), OneToOneExistsFilterSpec))
#