7. Extending the navigation menu¶

7.1. Create the navigation menu¶

We create the menu using a CMSAttachMenu sub-class, and use the get_nodes() method to add the nodes.

For this we need a file called cms_menus.py in our application. Add cms_menus.py in polls_cms_integration/:

from django.urls import reverse
from django.utils.translation import gettext_lazy as _

from cms.menu_bases import CMSAttachMenu
from menus.base import NavigationNode
from menus.menu_pool import menu_pool

from polls.models import Poll


class PollsMenu(CMSAttachMenu):
    name = _("Polls Menu")  # give the menu a name this is required.

    def get_nodes(self, request):
        """
        This method is used to build the menu tree.
        """
        nodes = []
        for poll in Poll.objects.all():
            node = NavigationNode(
                title=poll.question,
                url=reverse('polls:detail', args=(poll.pk,)),
                id=poll.pk,  # unique id for this node within the menu
            )
            nodes.append(node)
        return nodes

menu_pool.register_menu(PollsMenu)

What’s happening here:

• we define a PollsMenu class, and register it

• we give the class a name attribute (will be displayed in admin)

• in its get_nodes() method, we build and return a list of nodes, where:

• first we get all the Poll objects

• … and then create a NavigationNode object from each one

• … and return a list of these NavigationNodes

This menu class won’t actually do anything until attached to a page. In the Advanced settings of the page to which you attached the apphook earlier, select “Polls Menu” from the list of Attached menu options, and save once more. (You could add the menu to any page, but it makes most sense to add it to this page.)

You can force the menu to be added automatically to the page by the apphook if you consider this appropriate. See Adding menus to apphooks for information on how to do that.