Categories & Subcategories With Django

By VoiDeT on December 11, 2008, 353 views

<code>class Category(models.Model):
name = models.CharField(core=True, maxlength=200)
slug = models.SlugField(prepopulate_from=(‘name’,))
parent = models.ForeignKey(‘self’, blank=True, null=True, related_name=’child’)
description = models.TextField(blank=True,help_text=”Optional”)

class Admin: list_display = ('name', '_parents_repr')

def __str__(self): p_list = self._recurse_for_parents(self) p_list.append(self.name) return self.get_separator().join(p_list)


def get_absolute_url(self):

if self.parent_id:

return "/tag/%s/%s/" % (self.parent.slug, self.slug)

else:

return "/tag/%s/" % (self.slug)
def _recurse_for_parents(self, cat_obj):

p_list = []

if cat_obj.parent_id:

p = cat_obj.parent

p_list.append(p.name)

more = self._recurse_for_parents(p)

p_list.extend(more)

if cat_obj == self and p_list:

p_list.reverse()

return p_list
def get_separator(self):

return ' :: '
def _parents_repr(self):

p_list = self._recurse_for_parents(self)

return self.get_separator().join(p_list)

_parents_repr.short_description = "Tag parents"

def save(self): p_list = self._recurse_for_parents(self) if self.name in p_list: raise validators.ValidationError("You must not save a category in itself!") super(Category, self).save()

http://code.djangoproject.com/wiki/CookBookCategoryDataModelPostMagic