lazy loading of the menu on page change list

cms/admin/pageadmin.py

@@ -204,6 +204,7 @@ def get_urls(self):
             pat(r'^([0-9]+)/remove-delete-state/$', self.remove_delete_state),
             pat(r'^([0-9]+)/dialog/copy/$', get_copy_dialog), # copy dialog
             pat(r'^([0-9]+)/preview/$', self.preview_page), # copy dialog
+            pat(r'^([0-9]+)/load-nav/$', self.load_nav), # lazy load navigation
             pat(r'^(?P<object_id>\d+)/change_template/$', self.change_template), # copy dialog
         )
 
@@ -683,6 +684,7 @@ def changelist_view(self, request, extra_context=None):
             'has_recover_permission': 'reversion' in settings.INSTALLED_APPS and self.has_recover_permission(request),
             'DEBUG': settings.DEBUG,
             'site_languages': languages,
+            'CMS_LAZY_LOAD_MENU': settings.CMS_LAZY_LOAD_MENU,
         }
         if 'reversion' in settings.INSTALLED_APPS:
             context['has_change_permission'] = self.has_change_permission(request)
@@ -1065,6 +1067,19 @@ def change_innavigation(self, request, page_id):
             return admin_utils.render_admin_menu_item(request, page)
         return HttpResponseForbidden(_("You do not have permission to change this page's in_navigation status"))
 
+    def load_nav(self, request, page_id):
+        """
+        Lazy load navigation tree for given page
+        """
+        page = get_object_or_404(Page, pk=page_id)
+        return admin_utils.render_admin_menu_item(request, page,
+                template="admin/cms/page/lazy_menu.html")
+        # return render_to_response("admin/cms/page/lazy_menu.html", {
+        #         "page":page,
+        #         "children":page.children.all(),
+        #         "filtered":False, #need to actually set this
+        #     }, context_instance=RequestContext(request))
+
     @create_on_success
     def add_plugin(self, request):
         '''

cms/conf/global_settings.py

@@ -122,4 +122,5 @@
 
 # they are missing in the permission-merge2 branch
 CMS_PLUGIN_PROCESSORS = tuple()
-CMS_PLUGIN_CONTEXT_PROCESSORS = tuple()
+CMS_PLUGIN_CONTEXT_PROCESSORS = tuple()
+CMS_LAZY_LOAD_MENU = False

cms/static/cms/js/change_list.js

@@ -36,7 +36,7 @@
 				theme_name: "default",
 				a_class: "title"
 			},
-			cookies : {},
+			cookies : MENU_COOKIES,
 			callback: {
 				beforemove  : function(what, where, position, tree) {
 					item_id = what.id.split("page_")[1];

cms/static/cms/js/libs/lazyloadmenu.js

@@ -0,0 +1,17 @@
+(function($) {
+    $(function() {
+        admin_base_url = document.URL.split("/cms/page/")[0] + "/";
+        $(".tree-default li").click(function(event) { 
+            var target = event.target;
+            var page_id = $(target).attr("id").split("page_")[1];
+            var load_nav_url = admin_base_url + "cms/page/" + page_id + "/load-nav/";
+            if($(target).hasClass("closed")) {
+                if($(target).children('ul').children('li').length == 0) {
+                    $.get(load_nav_url, {}, function(r, status) {
+                        $(target).children('ul').append(r);    
+                    });
+                }
+            } 
+        });
+    });
+})(jQuery.noConflict());

cms/templates/admin/cms/page/change_list.html

@@ -12,6 +12,13 @@
 
 {% block coltype %}flex{% endblock %}
 {% block extrahead %}
+<script type="text/javascript">
+	{% if CMS_LAZY_LOAD_MENU %}
+	MENU_COOKIES = false;
+	{% else %}
+	MENU_COOKIES = true;
+	{% endif %}
+</script>
 <link rel="stylesheet" type="text/css" href="{{ STATIC_URL }}cms/css/pages.css"/>
 <link rel="stylesheet" type="text/css" href="{{ STATIC_URL }}cms/jstree/tree_component.css" />
 <link rel="stylesheet" type="text/css" href="{{ STATIC_URL }}cms/css/jquery.dialog.css" />
@@ -34,6 +41,7 @@
 <script type="text/javascript" src="{{ STATIC_URL }}cms/js/libs/classy.min.js"></script>
 <script type="text/javascript" src="{{ STATIC_URL }}cms/js/plugins/cms.base.js"></script>
 <script type="text/javascript" src="{{ STATIC_URL }}cms/js/change_list.js"></script>
+<script type="text/javascript" src="{{ STATIC_URL }}cms/js/libs/lazyloadmenu.js"></script>
 
 
 {% if cl.is_filtered %}

cms/templates/admin/cms/page/lazy_child_menu.html

@@ -0,0 +1,12 @@
+{% load cms_admin i18n adminmedia %}<li id="page_{{page.pk}}" class="{% if cl.is_filtered %}leaf{% endif %}{% if has_move_page_permission %} moveable{% endif %}{%if page.children.all %} closed{% endif %}"{% if metadata %} mdata="{{ metadata }}{% endif %}" rel="{% ifequal page.level 0 %}topnode{% else %}node{% endifequal %}">
+
+    {% include 'admin/cms/page/menu_item.html' %}
+
+    {% with page.children as children %}
+        {% if children %}<ul{% if page.last %} class="last"{% endif %}>{% for child in children.all %}
+            {# show_lazy_admin_menu child #}{% endfor %}
+        </ul>{% endif %}
+    {% endwith %}
+</li>
+
+

cms/templates/admin/cms/page/lazy_menu.html

@@ -0,0 +1,8 @@
+{% load cms_admin i18n adminmedia %}
+    {% with page.children.all as children %}
+        {% if children %}
+            {% for child in children %}
+                {% show_lazy_admin_menu child %}
+            {% endfor %}
+        {% endif %}
+    {% endwith %}

cms/templates/admin/cms/page/menu.html

@@ -4,7 +4,10 @@
 
 	{% with page.childrens as children %}
 		{% if children %}<ul{% if page.last %} class="last"{% endif %}>{% for child in children %}
-			{% show_admin_menu child %}{% endfor %}
+            {% if not CMS_LAZY_LOAD_MENU %}
+			{% show_admin_menu child %}
+            {% endif %} 
+            {% endfor %}
 		</ul>{% endif %}
 	{% endwith %}
 </li>

cms/templatetags/cms_admin.py

@@ -46,6 +46,39 @@ def get_context(self, context, page):
         return context
 register.tag(ShowAdminMenu)
 
+class ShowLazyAdminMenu(InclusionTag):
+    name = 'show_lazy_admin_menu'
+    template = 'admin/cms/page/lazy_child_menu.html'
+
+    options = Options(
+        Argument('page')
+    )
+
+    def get_context(self, context, page):
+        request = context['request']
+
+
+        if context.has_key("cl"):
+            filtered = context['cl'].is_filtered()
+        elif context.has_key('filtered'):
+            filtered = context['filtered']
+
+
+
+        # following function is newly used for getting the context per item (line)
+        # if something more will be required, then get_admin_menu_item_context
+        # function have to be updated. 
+        # This is done because item can be reloaded after some action over ajax.
+        context.update(get_admin_menu_item_context(request, page, filtered))
+
+        # this here is just context specific for menu rendering - items itself does
+        # not use any of following variables
+        #context.update({
+        #    'no_children': no_children,
+        #})
+        return context
+register.tag(ShowLazyAdminMenu)
+
 
 class CleanAdminListFilter(InclusionTag):
     """

cms/utils/admin.py

@@ -71,11 +71,14 @@ def get_admin_menu_item_context(request, page, filtered=False):
     return context
 
 
-def render_admin_menu_item(request, page):
+def render_admin_menu_item(request, page, template=None):
     """
     Renders requested page item for the tree. This is used in case when item
     must be reloaded over ajax.
     """
+    if not template:
+        template = "admin/cms/page/menu_item.html"
+
     if not page.pk:
         return HttpResponse(NOT_FOUND_RESPONSE) # Not found - tree will remove item
 
@@ -93,4 +96,4 @@ def render_admin_menu_item(request, page):
 
     filtered = 'filtered' in request.REQUEST
     context.update(get_admin_menu_item_context(request, page, filtered))
-    return render_to_response('admin/cms/page/menu_item.html', context)
+    return render_to_response(template, context)

docs/getting_started/configuration.rst

@@ -179,6 +179,14 @@ Default: ``True``
 If set to ``False``, frontend editing is not available for models using
 :class:`cms.models.fields.PlaceholderField`.
 
+CMS_LAZY_LOAD_MENU
+==================
+
+Default: ``False``
+
+If set to ``True``, it will enabled lazy loading of the menu in the page
+change list in the admin.  This is useful for sites with a lot of menu items as loading a large menu tree affects site performance
+
 ********************
 Editor configuration
 ********************