Класс MultipleObjectMixin (Django 2.2)
from django.views.generic.list import MultipleObjectMixin
A mixin for views manipulating multiple objects.
Предки (MRO)
- MultipleObjectMixin
- ContextMixin
Атрибуты
Определено в | |
---|---|
allow_empty = True
|
MultipleObjectMixin |
context_object_name = None
|
MultipleObjectMixin |
extra_context = None
|
ContextMixin |
model = None
|
MultipleObjectMixin |
ordering = None
|
MultipleObjectMixin |
page_kwarg = 'page'
|
MultipleObjectMixin |
paginate_by = None
|
MultipleObjectMixin |
paginate_orphans = 0
|
MultipleObjectMixin |
paginator_class = <class 'django.core.paginator.Paginator'>
|
MultipleObjectMixin |
queryset = None
|
MultipleObjectMixin |
Методы
Return ``True`` if the view should display empty lists and ``False`` if a 404 should be raised instead.
def get_allow_empty(self):
"""
Return ``True`` if the view should display empty lists and ``False``
if a 404 should be raised instead.
"""
return self.allow_empty
MultipleObjectMixin
Get the context for this view.
def get_context_data(self, *, object_list=None, **kwargs):
"""Get the context for this view."""
queryset = object_list if object_list is not None else self.object_list
page_size = self.get_paginate_by(queryset)
context_object_name = self.get_context_object_name(queryset)
if page_size:
paginator, page, queryset, is_paginated = self.paginate_queryset(queryset, page_size)
context = {
'paginator': paginator,
'page_obj': page,
'is_paginated': is_paginated,
'object_list': queryset
}
else:
context = {
'paginator': None,
'page_obj': None,
'is_paginated': False,
'object_list': queryset
}
if context_object_name is not None:
context[context_object_name] = queryset
context.update(kwargs)
return super().get_context_data(**context)
ContextMixin
def get_context_data(self, **kwargs):
kwargs.setdefault('view', self)
if self.extra_context is not None:
kwargs.update(self.extra_context)
return kwargs
Get the name of the item to be used in the context.
def get_context_object_name(self, object_list):
"""Get the name of the item to be used in the context."""
if self.context_object_name:
return self.context_object_name
elif hasattr(object_list, 'model'):
return '%s_list' % object_list.model._meta.model_name
else:
return None
Return the field or fields to use for ordering the queryset.
def get_ordering(self):
"""Return the field or fields to use for ordering the queryset."""
return self.ordering
Get the number of items to paginate by, or ``None`` for no pagination.
def get_paginate_by(self, queryset):
"""
Get the number of items to paginate by, or ``None`` for no pagination.
"""
return self.paginate_by
Return the maximum number of orphans extend the last page by when paginating.
def get_paginate_orphans(self):
"""
Return the maximum number of orphans extend the last page by when
paginating.
"""
return self.paginate_orphans
Return an instance of the paginator for this view.
def get_paginator(self, queryset, per_page, orphans=0,
allow_empty_first_page=True, **kwargs):
"""Return an instance of the paginator for this view."""
return self.paginator_class(
queryset, per_page, orphans=orphans,
allow_empty_first_page=allow_empty_first_page, **kwargs)
Return the list of items for this view. The return value must be an iterable and may be an instance of `QuerySet` in which case `QuerySet` specific behavior will be enabled.
def get_queryset(self):
"""
Return the list of items for this view.
The return value must be an iterable and may be an instance of
`QuerySet` in which case `QuerySet` specific behavior will be enabled.
"""
if self.queryset is not None:
queryset = self.queryset
if isinstance(queryset, QuerySet):
queryset = queryset.all()
elif self.model is not None:
queryset = self.model._default_manager.all()
else:
raise ImproperlyConfigured(
"%(cls)s is missing a QuerySet. Define "
"%(cls)s.model, %(cls)s.queryset, or override "
"%(cls)s.get_queryset()." % {
'cls': self.__class__.__name__
}
)
ordering = self.get_ordering()
if ordering:
if isinstance(ordering, str):
ordering = (ordering,)
queryset = queryset.order_by(*ordering)
return queryset
Разбивает запрос на страницы, если необходимо.
def paginate_queryset(self, queryset, page_size):
"""Paginate the queryset, if needed."""
paginator = self.get_paginator(
queryset, page_size, orphans=self.get_paginate_orphans(),
allow_empty_first_page=self.get_allow_empty())
page_kwarg = self.page_kwarg
page = self.kwargs.get(page_kwarg) or self.request.GET.get(page_kwarg) or 1
try:
page_number = int(page)
except ValueError:
if page == 'last':
page_number = paginator.num_pages
else:
raise Http404(_("Page is not 'last', nor can it be converted to an int."))
try:
page = paginator.page(page_number)
return (paginator, page, page.object_list, page.has_other_pages())
except InvalidPage as e:
raise Http404(_('Invalid page (%(page_number)s): %(message)s') % {
'page_number': page_number,
'message': str(e)
})