add support for django admin filters

adminsortable/admin.py

@@ -109,14 +109,21 @@ class SortableAdmin(SortableAdminBase, ModelAdmin):
         """
         # get sort group index from querystring if present
         sort_filter_index = request.GET.get('sort_filter')
+        filter_expression = request.GET.get('filter_expression')
 
         filters = {}
+
         if sort_filter_index:
             try:
                 filters = self.model.sorting_filters[int(sort_filter_index)][1]
             except (IndexError, ValueError):
                 pass
 
+        if filter_expression:
+            filters.update(
+                dict([filter_expression.split('=')])
+            )
+
         # Apply any sort filters to create a subset of sortable objects
         return self.get_queryset(request).filter(**filters)
 

adminsortable/templates/adminsortable/change_list.html

@@ -29,6 +29,23 @@
 <script src="{% static 'adminsortable/js/jquery.ui.touch-punch.min.js' %}"></script>
 {% include 'adminsortable/csrf/jquery.django-csrf.html' with csrf_cookie_name=csrf_cookie_name %}
 <script src="{% static 'adminsortable/js/admin.sortable.js' %}"></script>
+
+<script type="text/javascript">
+(function($) {
+    $(document).ready(function($) {
+        var url = window.location.href;
+        var urlParts = url.split('?');
+        var cnangeListUrl = $('a#return-to-changelist').attr('href')
+
+        if (urlParts.length === 2) {
+            $('a#return-to-changelist').attr(
+                'href',
+                cnangeListUrl + '?' + urlParts[1].replace('filter_expression=', '')
+            );
+        }
+    });
+})(django.jQuery);
+</script>
 {% endblock %}
 
 {% block bodyclass %}{{ block.super }} app-{{ opts.app_label }} model-{{ opts.model_name }} change-list{% endblock %}
@@ -77,7 +94,7 @@
 		{% block object-tools %}
       <ul class="object-tools">
         <li>
-          <a href="{% url opts|admin_urlname:'changelist' %}">
+          <a id="return-to-changelist" href="{% url opts|admin_urlname:'changelist' %}">
           {% blocktrans with opts.verbose_name_plural|capfirst as model %}Return to {{ model }}{% endblocktrans %}
           </a>
         </li>

adminsortable/templates/adminsortable/change_list_with_sort_link.html

@@ -1,6 +1,23 @@
 {% extends change_list_template_extends %}
 {% load i18n %}
 
+{% block extrahead %}
+    {{ block.super }}
+    <script type="text/javascript">
+    (function($) {
+        $(document).ready(function($) {
+            var url = window.location.href;
+            var urlParts = url.split('?');
+
+            if (urlParts.length === 2) {
+                $('a#change-order').attr('href', './sort/?filter_expression=' + urlParts[1]);
+            }
+        });
+    })(django.jQuery);
+    </script>
+{% endblock %}
+
+
 {% block object-tools-items %}
     {% for sorting_filter in sorting_filters %}
     <li>
@@ -8,7 +25,7 @@
     </li>
     {% empty %}
     <li>
-        <a href="./sort/">{% trans 'Change Order' %}</a>
+        <a id="change-order" href="./sort/">{% trans 'Change Order' %}</a>
     </li>
     {% endfor %}
     {{ block.super }}