Listing view supports singleton object, for example, news item, atdoc…

…ument.

src/collective/listingviews/browser/views/base.py

@@ -110,12 +110,25 @@ def retrieve_context_item(self):
         return []
 
     def retrieve_listing_items(self):
-        raise Exception("Not implemented")
+        return []
 
     @property
     def number_of_items(self):
         return 0
 
+    @property
+    def listing_style_class(self):
+        style_class = ""
+        if self.view_setting:
+            style_class = getattr(self.view_setting, 'css_class', '')
+        if style_class is None:
+            style_class = ""
+        return style_class
+
+    @property
+    def listing_view_batch_size(self):
+        return 0
+
     @property
     def is_container(self):
         """

src/collective/listingviews/browser/views/basic.py

@@ -33,15 +33,6 @@ def listing_fields(self):
             fields = []
         return fields
 
-    @property
-    def listing_style_class(self):
-        style_class = ""
-        if self.view_setting:
-            style_class = getattr(self.view_setting, 'css_class', '')
-        if style_class is None:
-            style_class = ""
-        return style_class
-
     @property
     def listing_view_batch_size(self):
         batch_size = 0

src/collective/listingviews/browser/views/configure.zcml

@@ -63,6 +63,10 @@
       class=".collection.BasicCollectionListingInformationRetriever"
       permission="zope2.View"
        zcml:condition="installed plone.app.collection"/>
-
+  <browser:page
+      for="*"
+      name="listing_view_adapter"
+      class=".base.BaseListingInformationRetriever"
+      permission="zope2.View" />
 
 </configure>

src/collective/listingviews/interfaces.py

@@ -150,6 +150,16 @@ def number_of_items(self):
         Total items of the current list
         """
 
+    def listing_style_class(self):
+        """
+        Listing view css class
+        """
+
+    def listing_view_batch_size(self):
+        """
+        Batch size
+        """
+
     def set_listing_view(self, view_name):
         """
         Set id of the view to one of the available views stored in the registry.