AdminThumbnailView is now AdminThumbnail

I never liked that the "AdminThumbnailView" was supposed to be defined
on the model, but never looked into it.

This commit puts the definition back where it belongs: in the admin.
Instead of requiring you to add a field (with view logic) to your
model, you now just add a property to your admin class and specify
that property in the `list_display` list.

README.rst

@@ -83,35 +83,25 @@ implement a ``process()`` method::
 Admin
 -----
 
-ImageKit also contains a class named ``imagekit.models.AdminThumbnailView``
+ImageKit also contains a class named ``imagekit.admin.AdminThumbnail``
 for displaying specs (or even regular ImageFields) in the
-`Django admin change list`__. Like ``imagekit.models.ImageSpec``,
-AdminThumbnailView is used as a property on Django model classes::
-
-    from django.db import models
-    from imagekit.models import ImageSpec, AdminThumbnailView
-    from imagekit.processors import resize 
-
-    class Photo(models.Model):
-        original_image = models.ImageField(upload_to'photos')
-        thumbnail = ImageSpec([resize.Crop(50, 50)], image_field='original_image')
-        admin_thumbnail_view = AdminThumbnailView(image_field='thumbnail')
-
-You can then add this property to the `list_display`__ field of your admin
-class::
+`Django admin change list`__. AdminThumbnail is used as a property on
+Django admin classes::
 
     from django.contrib import admin
+    from imagekit.admin import AdminThumbnail
     from .models import Photo
 
 
     class PhotoAdmin(admin.ModelAdmin):
-        list_display = ('__str__', 'admin_thumbnail_view')
+        list_display = ('__str__', 'admin_thumbnail')
+        admin_thumbnail = AdminThumbnail(image_field='thumbnail')
 
 
     admin.site.register(Photo, PhotoAdmin)
 
-AdminThumbnailView can even use a custom template. For more information, see
-``imagekit.models.AdminThumbnailView``.
+AdminThumbnail can even use a custom template. For more information, see
+``imagekit.admin.AdminThumbnail``.
 
 
 __ https://docs.djangoproject.com/en/dev/intro/tutorial02/#customize-the-admin-change-list

docs/apireference.rst

@@ -8,6 +8,7 @@ API Reference
 .. automodule:: imagekit.models
    :members:
 
+
 :mod:`processors` Module
 ------------------------
 
@@ -16,3 +17,10 @@ API Reference
 
 .. automodule:: imagekit.processors.resize
   :members:
+
+
+:mod:`admin` Module
+--------------------
+
+.. automodule:: imagekit.admin
+   :members:

imagekit/admin.py

@@ -0,0 +1,37 @@
+from django.utils.translation import ugettext_lazy as _
+from django.template.loader import render_to_string
+
+
+class AdminThumbnail(object):
+    """A convenience utility for adding thumbnails to the Django admin change
+    list.
+
+    """
+    short_description = _('Thumbnail')
+    allow_tags = True
+
+    def __init__(self, image_field, template=None):
+        """
+        :param image_field: The name of the ImageField or ImageSpec on the model
+                to use for the thumbnail.
+        :param template: The template with which to render the thumbnail
+
+        """
+        self.image_field = image_field
+        self.template = template
+
+    def __call__(self, obj):
+        thumbnail = getattr(obj, self.image_field, None)
+        
+        if not thumbnail:
+            raise Exception('The property {0} is not defined on {1}.'.format(
+                    obj, self.image_field))
+
+        original_image = getattr(thumbnail, 'source_file', None) or thumbnail
+        template = self.template or 'imagekit/admin/thumbnail.html'
+
+        return render_to_string(template, {
+            'model': obj,
+            'thumbnail': thumbnail,
+            'original_image': original_image,
+        })

imagekit/models.py

@@ -9,8 +9,6 @@ from django.core.files.base import ContentFile
 from django.utils.encoding import force_unicode, smart_str
 from django.db import models
 from django.db.models.signals import post_save, post_delete
-from django.utils.translation import ugettext_lazy as _
-from django.template.loader import render_to_string
 from django.db.models.fields.files import ImageFieldFile
 
 
@@ -299,58 +297,6 @@ def _post_delete_handler(sender, instance=None, **kwargs):
         spec_file._delete()
 
 
-class AdminThumbnailView(object):
-    """A convenience utility for adding thumbnails to the Django admin change
-    list.
-
-    """
-    short_description = _('Thumbnail')
-    allow_tags = True
-
-    def __init__(self, image_field, template=None):
-        """
-        :param image_field: The name of the ImageField or ImageSpec on the model
-                to use for the thumbnail.
-        :param template: The template with which to render the thumbnail
-
-        """
-        self.image_field = image_field
-        self.template = template
-
-    def __get__(self, instance, owner):
-        if instance is None:
-            return self
-        else:
-            return BoundAdminThumbnailView(instance, self)
-
-
-class BoundAdminThumbnailView(AdminThumbnailView):
-    def __init__(self, model_instance, unbound_field):
-        super(BoundAdminThumbnailView, self).__init__(unbound_field.image_field,
-                unbound_field.template)
-        self.model_instance = model_instance
-
-    def __unicode__(self):
-        thumbnail = getattr(self.model_instance, self.image_field, None)
-        
-        if not thumbnail:
-            raise Exception('The property {0} is not defined on {1}.'.format(
-                    self.model_instance, self.image_field))
-
-        original_image = getattr(thumbnail, 'source_file', None) or thumbnail
-        template = self.template or 'imagekit/admin/thumbnail.html'
-
-        return render_to_string(template, {
-            'model': self.model_instance,
-            'thumbnail': thumbnail,
-            'original_image': original_image,
-        })
-    
-    def __get__(self, instance, owner):
-        """Override AdminThumbnailView's implementation."""
-        return self
-
-
 class ProcessedImageFieldFile(ImageFieldFile, _ImageSpecFileMixin):
     def save(self, name, content, save=True):
         new_filename = self.field.generate_filename(self.instance, name)

imagekit/tests.py

@@ -4,7 +4,7 @@ import Image
 from django.core.files.base import ContentFile
 from django.db import models
 from django.test import TestCase
-from imagekit.models import ImageSpec, AdminThumbnailView
+from imagekit.models import ImageSpec
 from imagekit.processors.resize import Crop
 from imagekit.processors import Adjust
 
@@ -14,8 +14,7 @@ class Photo(models.Model):
     original_image = models.ImageField(upload_to='photos')
     thumbnail = ImageSpec([Adjust(contrast=1.2, sharpness=1.1), Crop(50, 50)],
             image_field='original_image', format='JPEG', quality=90)
-    admin_thumbnail_view = AdminThumbnailView(image_field='thumbnail')
-    
+
 
 class IKTest(TestCase):
     """ Base TestCase class """