Commit 61524b09 authored by Tim Graham's avatar Tim Graham
Browse files

Fixed #18388 - Added InlineModelAdmin.get_max_num hook. 

Thanks d.willy.c.c@ for the suggestion and Melevir and Areski Belaid for work
on the patch.
parent 07a73a27

django/contrib/admin/options.py

+5 −1
Original line number Diff line number Diff line
@@ -1516,6 +1516,10 @@ class InlineModelAdmin(BaseModelAdmin): 
        """Hook for customizing the number of extra inline forms."""

        return self.extra



    def get_max_num(self, request, obj=None, **kwargs):

        """Hook for customizing the max number of extra inline forms."""

        return self.max_num



    def get_formset(self, request, obj=None, **kwargs):

        """Returns a BaseInlineFormSet class for use in admin add/change views."""

        if 'fields' in kwargs:
@@ -1543,7 +1547,7 @@ class InlineModelAdmin(BaseModelAdmin): 
            "exclude": exclude,

            "formfield_callback": partial(self.formfield_for_dbfield, request=request),

            "extra": self.get_extra(request, obj, **kwargs),

            "max_num": self.max_num,

            "max_num": self.get_max_num(request, obj, **kwargs),

            "can_delete": can_delete,

        }

docs/ref/contrib/admin/index.txt

+26 −0
Original line number Diff line number Diff line
@@ -1728,6 +1728,11 @@ The ``InlineModelAdmin`` class adds: 
    doesn't directly correlate to the number of objects, but can if the value

    is small enough. See :ref:`model-formsets-max-num` for more information.



    .. versionadded:: 1.6



    :meth:`InlineModelAdmin.get_max_num` also allows you to customize the

    maximum number of extra forms.



.. attribute:: InlineModelAdmin.raw_id_fields



    By default, Django's admin uses a select-box interface (<select>) for
@@ -1787,6 +1792,27 @@ The ``InlineModelAdmin`` class adds: 
                    return extra - obj.binarytree_set.count()

                return extra



.. method:: InlineModelAdmin.get_max_num(self, request, obj=None, **kwargs)



    .. versionadded:: 1.6



    Returns the maximum number of extra inline forms to use. By default,

    returns the :attr:`InlineModelAdmin.max_num` attribute.



    Override this method to programmatically determine the maximum number of

    inline forms. For example, this may be based on the model instance

    (passed as the keyword argument ``obj``)::



        class BinaryTreeAdmin(admin.TabularInline):

            model = BinaryTree



            def get_max_num(self, request, obj=None, **kwargs):

                max_num = 10

                if obj.parent:

                    return max_num - 5

                return max_num





Working with a model with two or more foreign keys to the same parent model

---------------------------------------------------------------------------

docs/releases/1.6.txt

+3 −2
Original line number Diff line number Diff line
@@ -292,9 +292,10 @@ Minor features 
  :meth:`~django.db.models.query.QuerySet.select_related` can be cleared using

  ``select_related(None)``.



* The :meth:`~django.contrib.admin.InlineModelAdmin.get_extra` method on

* The :meth:`~django.contrib.admin.InlineModelAdmin.get_extra` and

  :meth:`~django.contrib.admin.InlineModelAdmin.get_max_num` methods on

  :class:`~django.contrib.admin.InlineModelAdmin` may be overridden to

  customize the number of extra inline forms.

  customize the extra and maximum number of inline forms.



Backwards incompatible changes in 1.6

=====================================

tests/admin_inlines/admin.py

+7 −2
Original line number Diff line number Diff line
@@ -129,7 +129,7 @@ class ChildModel1Inline(admin.TabularInline): 
class ChildModel2Inline(admin.StackedInline):

    model = ChildModel2



# admin for #19425

# admin for #19425 and #18388

class BinaryTreeAdmin(admin.TabularInline):

    model = BinaryTree
@@ -137,9 +137,14 @@ class BinaryTreeAdmin(admin.TabularInline): 
        extra = 2

        if obj:

            return extra - obj.binarytree_set.count()



        return extra



    def get_max_num(self, request, obj=None, **kwargs):

        max_num = 3

        if obj:

            return max_num - obj.binarytree_set.count()

        return max_num



# admin for #19524

class SightingInline(admin.TabularInline):

    model = Sighting

tests/admin_inlines/tests.py

+6 −0
Original line number Diff line number Diff line
@@ -197,12 +197,18 @@ class TestInline(TestCase): 
        bt_head = BinaryTree.objects.create(name="Tree Head")

        bt_child = BinaryTree.objects.create(name="First Child", parent=bt_head)



        # The maximum number of forms should respect 'get_max_num' on the

        # ModelAdmin

        max_forms_input = '<input id="id_binarytree_set-MAX_NUM_FORMS" name="binarytree_set-MAX_NUM_FORMS" type="hidden" value="%d" />'

        # The total number of forms will remain the same in either case

        total_forms_hidden = '<input id="id_binarytree_set-TOTAL_FORMS" name="binarytree_set-TOTAL_FORMS" type="hidden" value="2" />'



        response = self.client.get('/admin/admin_inlines/binarytree/add/')

        self.assertContains(response, max_forms_input % 3)

        self.assertContains(response, total_forms_hidden)



        response = self.client.get("/admin/admin_inlines/binarytree/%d/" % bt_head.id)

        self.assertContains(response, max_forms_input % 2)

        self.assertContains(response, total_forms_hidden)