newforms-admin: Fixed #7541 -- RelatedFieldWidgetWrapper now wraps the widget and not the just the render function which caused some stale values. Thanks lukas and Doug Napoleone.

brosner · brosner · commit c349ba4cfc2d · 2008-06-26T16:53:53.000Z
git-svn-id: http://code.djangoproject.com/svn/django/branches/newforms-admin@7771 bcc190cf-cafb-0310-a4f2-bffc1f526a37
diff --git a/django/contrib/admin/options.py b/django/contrib/admin/options.py
@@ -198,7 +198,7 @@ def formfield_for_dbfield(self, db_field, **kwargs):
             formfield = db_field.formfield(**kwargs)
             # Don't wrap raw_id fields. Their add function is in the popup window.
             if not db_field.name in self.raw_id_fields:
-                formfield.widget.render = widgets.RelatedFieldWidgetWrapper(formfield.widget.render, db_field.rel, self.admin_site)
+                formfield.widget = widgets.RelatedFieldWidgetWrapper(formfield.widget, db_field.rel, self.admin_site)
             return formfield
         
         if db_field.choices and db_field.name in self.radio_fields:
diff --git a/django/contrib/admin/widgets.py b/django/contrib/admin/widgets.py
@@ -2,6 +2,8 @@
 Form Widget classes specific to the Django admin site.
 """
 
+import copy
+
 from django import newforms as forms
 from django.newforms.widgets import RadioFieldRenderer
 from django.newforms.util import flatatt
@@ -162,21 +164,34 @@ def _has_changed(self, initial, data):
                 return True
         return False
 
-class RelatedFieldWidgetWrapper(object):
+class RelatedFieldWidgetWrapper(forms.Widget):
     """
-    This class is a wrapper whose __call__() method mimics the interface of a
-    Widget's render() method.
+    This class is a wrapper to a given widget to add the add icon for the
+    admin interface.
     """
-    def __init__(self, render_func, rel, admin_site):
-        self.render_func, self.rel = render_func, rel
+    def __init__(self, widget, rel, admin_site):
+        self.is_hidden = widget.is_hidden
+        self.needs_multipart_form = widget.needs_multipart_form
+        self.attrs = widget.attrs
+        self.choices = widget.choices
+        self.widget = widget
+        self.rel = rel
         # so we can check if the related object is registered with this AdminSite
         self.admin_site = admin_site
 
-    def __call__(self, name, value, *args, **kwargs):
+    def __deepcopy__(self, memo):
+        obj = copy.copy(self)
+        obj.widget = copy.deepcopy(self.widget, memo)
+        obj.attrs = self.widget.attrs
+        memo[id(self)] = obj
+        return obj
+
+    def render(self, name, value, *args, **kwargs):
         from django.conf import settings
         rel_to = self.rel.to
         related_url = '../../../%s/%s/' % (rel_to._meta.app_label, rel_to._meta.object_name.lower())
-        output = [self.render_func(name, value, *args, **kwargs)]
+        self.widget.choices = self.choices
+        output = [self.widget.render(name, value, *args, **kwargs)]
         if rel_to in self.admin_site._registry: # If the related object has an admin interface:
             # TODO: "id_" is hard-coded here. This should instead use the correct
             # API to determine the ID dynamically.
@@ -185,7 +200,16 @@ def __call__(self, name, value, *args, **kwargs):
             output.append(u'<img src="%simg/admin/icon_addlink.gif" width="10" height="10" alt="Add Another"/></a>' % settings.ADMIN_MEDIA_PREFIX)
         return mark_safe(u''.join(output))
 
-    def __deepcopy__(self, memo):
-        # There's no reason to deepcopy admin_site, etc, so just return self.
-        memo[id(self)] = self
-        return self
+    def build_attrs(self, extra_attrs=None, **kwargs):
+        "Helper function for building an attribute dictionary."
+        self.attrs = self.widget.build_attrs(extra_attrs=None, **kwargs)
+        return self.attrs
+
+    def value_from_datadict(self, data, files, name):
+        return self.widget.value_from_datadict(data, files, name)
+
+    def _has_changed(self, initial, data):
+        return self.widget._has_changed(initial, data)
+
+    def id_for_label(self, id_):
+        return self.widget.id_for_label(id_)
diff --git a/tests/regressiontests/modeladmin/models.py b/tests/regressiontests/modeladmin/models.py
@@ -122,21 +122,50 @@ class and an AdminSite instance, so let's just go ahead and do that manually
 >>> type(ma.get_form(request).base_fields['sign_date'].widget)
 <class 'django.contrib.admin.widgets.AdminDateWidget'>
 
+If we need to override the queryset of a ModelChoiceField in our custom form
+make sure that RelatedFieldWidgetWrapper doesn't mess that up.
+
+>>> band2 = Band(name='The Beetles', bio='', sign_date=date(1962, 1, 1))
+>>> band2.save()
+
+>>> class AdminConcertForm(forms.ModelForm):
+...     class Meta:
+...         model = Concert
+...
+...     def __init__(self, *args, **kwargs):
+...         super(AdminConcertForm, self).__init__(*args, **kwargs)
+...         self.fields["main_band"].queryset = Band.objects.filter(name='The Doors')
+
+>>> class ConcertAdmin(ModelAdmin):
+...     form = AdminConcertForm
+
+>>> ma = ConcertAdmin(Concert, site)
+>>> form = ma.get_form(request)()
+>>> print form["main_band"]
+<select name="main_band" id="id_main_band">
+<option value="" selected="selected">---------</option>
+<option value="1">The Doors</option>
+</select>
+
+>>> band2.delete()
+
 # radio_fields behavior ################################################
 
 First, without any radio_fields specified, the widgets for ForeignKey
 and fields with choices specified ought to be a basic Select widget.
-For Select fields, all of the choices lists have a first entry of dashes.
+ForeignKey widgets in the admin are wrapped with RelatedFieldWidgetWrapper so
+they need to be handled properly when type checking. For Select fields, all of
+the choices lists have a first entry of dashes.
 
 >>> cma = ModelAdmin(Concert, site)
 >>> cmafa = cma.get_form(request)
 
->>> type(cmafa.base_fields['main_band'].widget)
+>>> type(cmafa.base_fields['main_band'].widget.widget)
 <class 'django.newforms.widgets.Select'>
 >>> list(cmafa.base_fields['main_band'].widget.choices)
 [(u'', u'---------'), (1, u'The Doors')]
 
->>> type(cmafa.base_fields['opening_band'].widget)
+>>> type(cmafa.base_fields['opening_band'].widget.widget)
 <class 'django.newforms.widgets.Select'>
 >>> list(cmafa.base_fields['opening_band'].widget.choices)
 [(u'', u'---------'), (1, u'The Doors')]
@@ -152,7 +181,7 @@ class and an AdminSite instance, so let's just go ahead and do that manually
 [('', '---------'), (1, 'Plane'), (2, 'Train'), (3, 'Bus')]
 
 Now specify all the fields as radio_fields.  Widgets should now be
-RadioSelect, and the choices list should have a first entry of 'None' iff
+RadioSelect, and the choices list should have a first entry of 'None' if
 blank=True for the model field.  Finally, the widget should have the
 'radiolist' attr, and 'inline' as well if the field is specified HORIZONTAL.
 
@@ -167,14 +196,14 @@ class and an AdminSite instance, so let's just go ahead and do that manually
 >>> cma = ConcertAdmin(Concert, site)
 >>> cmafa = cma.get_form(request)
 
->>> type(cmafa.base_fields['main_band'].widget)
+>>> type(cmafa.base_fields['main_band'].widget.widget)
 <class 'django.contrib.admin.widgets.AdminRadioSelect'>
 >>> cmafa.base_fields['main_band'].widget.attrs
 {'class': 'radiolist inline'}
 >>> list(cmafa.base_fields['main_band'].widget.choices)
 [(1, u'The Doors')]
 
->>> type(cmafa.base_fields['opening_band'].widget)
+>>> type(cmafa.base_fields['opening_band'].widget.widget)
 <class 'django.contrib.admin.widgets.AdminRadioSelect'>
 >>> cmafa.base_fields['opening_band'].widget.attrs
 {'class': 'radiolist'}
