Fixed #16257 -- Added new `ModelAdmin.get_list_display_links()` method to allow for the dynamic display of links on the admin changelist. Thanks to graveyboat for the suggestion and initial patch.

git-svn-id: http://code.djangoproject.com/svn/django/trunk@17037 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/admin/options.py

@@ -650,6 +650,18 @@ class ModelAdmin(BaseModelAdmin):
         """
         return self.list_display
 
+    def get_list_display_links(self, request, list_display):
+        """
+        Return a sequence containing the fields to be displayed as links
+        on the changelist. The list_display parameter is the list of fields
+        returned by get_list_display().
+        """
+        if self.list_display_links or not list_display:
+            return self.list_display_links
+        else:
+            # Use only the first item in list_display as link
+            return list(list_display)[:1]
+
     def construct_change_message(self, request, form, formsets):
         """
         Construct a change message from a changed object.
@@ -1087,22 +1099,20 @@ class ModelAdmin(BaseModelAdmin):
 
     @csrf_protect_m
     def changelist_view(self, request, extra_context=None):
-        "The 'change list' admin view for this model."
+        """
+        The 'change list' admin view for this model.
+        """
         from django.contrib.admin.views.main import ERROR_FLAG
         opts = self.model._meta
         app_label = opts.app_label
         if not self.has_change_permission(request, None):
             raise PermissionDenied
 
+        list_display = self.get_list_display(request)
+        list_display_links = self.get_list_display_links(request, list_display)
+
         # Check actions to see if any are available on this changelist
         actions = self.get_actions(request)
-
-        list_display = self.get_list_display(request)
-
-        list_display_links = self.list_display_links
-        if not self.list_display_links and list_display:
-            list_display_links = list(list_display)[:1]
-
         if actions:
             # Add the action checkboxes if there are any actions available.
             list_display = ['action_checkbox'] +  list(list_display)

docs/ref/contrib/admin/index.txt

@@ -1044,6 +1044,16 @@ templates used by the :class:`ModelAdmin` views:
     displayed on the changelist view as described above in the
     :attr:`ModelAdmin.list_display` section.
 
+.. method:: ModelAdmin.get_list_display_links(self, request, list_display)
+
+    .. versionadded:: 1.4
+
+    The ``get_list_display_links`` method is given the ``HttpRequest`` and
+    the ``list`` or ``tuple`` returned by :meth:`ModelAdmin.get_list_display`.
+    It is expected to return a ``list`` or ``tuple`` of field names on the
+    changelist that will be linked to the change view, as described in the
+    :attr:`ModelAdmin.list_display_links` section.
+
 .. method:: ModelAdmin.get_urls(self)
 
     The ``get_urls`` method on a ``ModelAdmin`` returns the URLs to be used for

docs/releases/1.4.txt

@@ -124,13 +124,20 @@ to work similarly to how desktop GUIs do it. The new hook
 :meth:`~django.contrib.admin.ModelAdmin.get_ordering` for specifying the
 ordering dynamically (e.g. depending on the request) has also been added.
 
-``ModelAdmin.save_related()``
+New ``ModelAdmin`` methods
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-A new :meth:`~django.contrib.admin.ModelAdmin.save_related` hook was added to
+A new :meth:`~django.contrib.admin.ModelAdmin.save_related` method was added to
 :mod:`~django.contrib.admin.ModelAdmin` to ease the customization of how
 related objects are saved in the admin.
 
+Two other new methods,
+:meth:`~django.contrib.admin.ModelAdmin.get_list_display` and
+:meth:`~django.contrib.admin.ModelAdmin.get_list_display_links`
+were added to :class:`~django.contrib.admin.ModelAdmin` to enable the dynamic
+customization of fields and links to display on the admin
+change list.
+
 Admin inlines respect user permissions
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

tests/regressiontests/admin_changelist/admin.py

@@ -58,13 +58,20 @@ class ChordsBandAdmin(admin.ModelAdmin):
 
 
 class DynamicListDisplayChildAdmin(admin.ModelAdmin):
-    list_display = ('name', 'parent')
+    list_display = ('parent', 'name', 'age')
 
     def get_list_display(self, request):
-        my_list_display = list(self.list_display)
+        my_list_display = super(DynamicListDisplayChildAdmin, self).get_list_display(request)
         if request.user.username == 'noparents':
+            my_list_display = list(my_list_display)
             my_list_display.remove('parent')
-
         return my_list_display
 
+class DynamicListDisplayLinksChildAdmin(admin.ModelAdmin):
+    list_display = ('parent', 'name', 'age')
+    list_display_links = ['parent', 'name']
+
+    def get_list_display_links(self, request, list_display):
+        return ['age']
+
 site.register(Child, DynamicListDisplayChildAdmin)

tests/regressiontests/admin_changelist/models.py

@@ -7,6 +7,7 @@ class Parent(models.Model):
 class Child(models.Model):
     parent = models.ForeignKey(Parent, editable=False, null=True)
     name = models.CharField(max_length=30, blank=True)
+    age = models.IntegerField(null=True, blank=True)
 
 class Genre(models.Model):
     name = models.CharField(max_length=20)

tests/regressiontests/admin_changelist/tests.py

@@ -9,7 +9,8 @@ from django.test import TestCase
 from django.test.client import RequestFactory
 
 from .admin import (ChildAdmin, QuartetAdmin, BandAdmin, ChordsBandAdmin,
-    GroupAdmin, ParentAdmin, DynamicListDisplayChildAdmin, CustomPaginationAdmin,
+    GroupAdmin, ParentAdmin, DynamicListDisplayChildAdmin,
+    DynamicListDisplayLinksChildAdmin, CustomPaginationAdmin,
     FilteredChildAdmin, CustomPaginator, site as custom_site)
 from .models import (Child, Parent, Genre, Band, Musician, Group, Quartet,
     Membership, ChordsMusician, ChordsBand, Invitation)
@@ -41,7 +42,9 @@ class ChangeListTests(TestCase):
         new_child = Child.objects.create(name='name', parent=None)
         request = self.factory.get('/child/')
         m = ChildAdmin(Child, admin.site)
-        cl = ChangeList(request, Child, m.list_display, m.list_display_links,
+        list_display = m.get_list_display(request)
+        list_display_links = m.get_list_display_links(request, list_display)
+        cl = ChangeList(request, Child, list_display, list_display_links,
                 m.list_filter, m.date_hierarchy, m.search_fields,
                 m.list_select_related, m.list_per_page, m.list_max_show_all, m.list_editable, m)
         cl.formset = None
@@ -61,7 +64,9 @@ class ChangeListTests(TestCase):
         new_child = Child.objects.create(name='name', parent=new_parent)
         request = self.factory.get('/child/')
         m = ChildAdmin(Child, admin.site)
-        cl = ChangeList(request, Child, m.list_display, m.list_display_links,
+        list_display = m.get_list_display(request)
+        list_display_links = m.get_list_display_links(request, list_display)
+        cl = ChangeList(request, Child, list_display, list_display_links,
                 m.list_filter, m.date_hierarchy, m.search_fields,
                 m.list_select_related, m.list_per_page, m.list_max_show_all, m.list_editable, m)
         cl.formset = None
@@ -334,28 +339,31 @@ class ChangeListTests(TestCase):
         m = custom_site._registry[Child]
         request = _mocked_authenticated_request(user_noparents)
         response = m.changelist_view(request)
-        # XXX - Calling render here to avoid ContentNotRenderedError to be
-        # raised. Ticket #15826 should fix this but it's not yet integrated.
-        response.render()
         self.assertNotContains(response, 'Parent object')
 
+        list_display = m.get_list_display(request)
+        list_display_links = m.get_list_display_links(request, list_display)
+        self.assertEqual(list_display, ['name', 'age'])
+        self.assertEqual(list_display_links, ['name'])
+
         # Test with user 'parents'
         m = DynamicListDisplayChildAdmin(Child, admin.site)
         request = _mocked_authenticated_request(user_parents)
         response = m.changelist_view(request)
-        # XXX - #15826
-        response.render()
         self.assertContains(response, 'Parent object')
 
         custom_site.unregister(Child)
 
+        list_display = m.get_list_display(request)
+        list_display_links = m.get_list_display_links(request, list_display)
+        self.assertEqual(list_display, ('parent', 'name', 'age'))
+        self.assertEqual(list_display_links, ['parent'])
+
         # Test default implementation
         custom_site.register(Child, ChildAdmin)
         m = custom_site._registry[Child]
         request = _mocked_authenticated_request(user_noparents)
         response = m.changelist_view(request)
-        # XXX - #15826
-        response.render()
         self.assertContains(response, 'Parent object')
 
     def test_show_all(self):
@@ -386,3 +394,30 @@ class ChangeListTests(TestCase):
         cl.get_results(request)
         self.assertEqual(len(cl.result_list), 10)
 
+    def test_dynamic_list_display_links(self):
+        """
+        Regression tests for #16257: dynamic list_display_links support.
+        """
+        parent = Parent.objects.create(name='parent')
+        for i in range(1, 10):
+            Child.objects.create(id=i, name='child %s' % i, parent=parent, age=i)
+
+        superuser = User.objects.create(
+            username='superuser',
+            is_superuser=True)
+
+        def _mocked_authenticated_request(user):
+            request = self.factory.get('/child/')
+            request.user = user
+            return request
+
+        m = DynamicListDisplayLinksChildAdmin(Child, admin.site)
+        request = _mocked_authenticated_request(superuser)
+        response = m.changelist_view(request)
+        for i in range(1, 10):
+            self.assertContains(response, '<a href="%s/">%s</a>' % (i, i))
+
+        list_display = m.get_list_display(request)
+        list_display_links = m.get_list_display_links(request, list_display)
+        self.assertEqual(list_display, ('parent', 'name', 'age'))
+        self.assertEqual(list_display_links, ['age'])