Menus

Navutils represents menus using Menu and Node instances, each menu being a collection of node instances representing a menu link. Nodes may have children, which are also Node instances.

Let’s see a minimal example.

yourapp/menu.py:

from navutils import menu

main_menu = menu.Menu('main')
menu.register(main_menu)

# will be shown to everybody
blog = menu.Node(id='blog', label='Blog', pattern_name='blog:index')
main_menu.register(blog)

# nodes created with a pattern_name argument will use django reverse
assert blog.get_url() == '/blog'

# if you want to disable reversion, use the url argument
django = menu.Node(id='django',
                   label='Django project',
                   url='http://djangoproject.com',
                   link_attrs={'target': '_blank'})

# Each node instance can accept an arbitrary number of children
blog.children.add(
    menu.Node(id='last_entries',
              label='Last entries',
              pattern_name='blog:last_entries')
)
blog.children.add(
    menu.Node(id='archives', label='Archives', pattern_name='blog:archives')
)

# will be shown to anonymous users only
login = menu.AnonymousNode(id='login',
                           label='Login',
                           pattern_name='accounts_login',
                           link_attrs={'class': 'big-button'})
main_menu.register(login)

# will be shown to authenticated users only
logout = menu.AuthenticatedNode(id='logout',
                                label='Logout',
                                pattern_name='accounts_logout')
main_menu.register(logout)

yourapp/templates/index.html:

{% load navutils_tags %}
{% render_menu menu=menus.main user=request.user %}

For an anonymous user, this would output something like:

<nav class="main-menu">
    <ul>
        <li class="has-children menu-item">
            <a href="/blog">Blog<a>
            <ul class="sub-menu">
                <li class="menu-item">
                    <a href="/blog/latest">Latest entries</a>
                </li>
                <li class="menu-item">
                    <a href="/blog/archives">Archives</a>
                </li>
            </ul>
        </li>
        <li class="menu-item">
            <a href="http://djangoproject.com" target="_blank">Django project</a>
        </li>
        <li class="menu-item">
            <a href="/login" class="big-button">Login</a>
        </li>
    </ul>
</nav>

You can also directly set children nodes on parent instanciation with the children argument:

user = menu.Node(
    id='user',
    label='Greetings',
    pattern_name='user:dashboard',
    children=[
        menu.Node(id='logout', label='Logout', pattern_name='user:logout'),

        # you can nest children indefinitely
        menu.Node(
            id='settings',
            label='Settings',
            pattern_name='user:settings',
            children = [
                menu.Node(id='newsletter',
                          label='Newsletter',
                          pattern_name='user:settings:newsletter')
            ],
        ),
    ]
)

Nodes can be customized in many ways:

heavily_customized_node = menu.Node(
    'customized',
    'My custom menu',
    url='#',

    # a custom CSS class that will be applied to the node on rendering
    css_class='custom-class',

    # the <a> title attribute
    title='click me!',

    # a path to a custom template for rendering the node
    template='myapp/menu/mynode.html',

    # extra context you can use in your node template
    context={'foo': 'bar'},

    # a dict of attributes that will be applied as HTML attributes on the <li>
    attrs = {'style': 'background-color: white;'}

    # a dict of attributes that will be applied as HTML attributes on the <a>
    link_attrs = {'target': '_blank', 'data-something': 'fancy-stuff'}
)

from navutils import menu

main_menu = menu.Menu(id='main')
menu.register(main_menu)

login = menu.Node(id='login', label='Login', pattern_name='account_login')
main_menu.register(login)

from navutils import MenuMixin

class Login(MenuMixin, TemplateView):
    current_menu_item = 'login'

vip_node = menu.PermissionNode('vip',
                               label='VIP Area',
                               pattern_name='vip:index',
                               permission='access_vip_area')

permissions = ['myapp.access_vip_area', 'myapp.drink_champagne']
champagne_node = menu.AllPermissionsNode('champagne',
                                         label='Champagne!',
                                         pattern_name='vip:champagne',
                                         permissions=permissions)

permissions = ['myapp.can_party', 'myapp.can_have_fun']
have_a_good_time = menu.AnyPermissionsNode('good-time',
                                           label='Have a good time',
                                           pattern_name='good_time',
                                           permissions=permissions)

def can_drink_alcohol(user, context):
    return user.age >= 21 or user.looks_mature_for_his_age

drink_alcohol = menu.PassTestNode('drink',
                                  label='Have a beer',
                                  pattern_name='beer',
                                  test=can_drink_alcohol)

Breadcrumbs

Breadcrumbs are set up into views, and therefore can only be used with class-based views.

First of all, you’ll probably want to define a base mixin for all your views:

from navutils import BreadcrumbsMixin, Breadcrumb

class BaseMixin(BreadcrumbsMixin):
    def get_breadcrumbs(self):
        breadcrumbs = super(BaseMixin, self).get_breadcrumbs()
        breadcrumbs.append(Breadcrumb('Home', url='/'))
        return breadcrumbs

Then, you can inherit from this view everywhere:

# breadcrumbs = Home > Blog
class BlogView(BaseMixin):
    title = 'Blog'


# breadcrumbs = Home > Logout
class LogoutView(BaseMixin):
    title = 'Logout'

By default, the last element of the breadcrumb is deduced from the title attribute of the view. However, for a complex hierarchy, you are free to override the get_breadcrumbs method:

# you can trigger url reversing via pattern_name, as for menu nodes
class BlogMixin(BaseMixin)
    def get_breadcrumbs(self):
        breadcrumbs = super(BlogMixin, self).get_breadcrumbs()
        breadcrumbs.append(Breadcrumb('Blog', pattern_name='blog:index'))
        return breadcrumbs


# breadcrumbs = Home > Blog > Last entries
class BlogIndex(BlogMixin):
    title = 'Last entries'


# for dynamic titles, just override the get_title method
# breadcrumbs = Home > Blog > My category name
class CategoryDetail(BlogMixin, DetailView):

    model = Category

    def get_title(self):
        # assuming your Category model has a title field
        return self.object.title

The last step is to render the breadcrumbs in your template. The provided mixin takes care with passing data in the context, so all you need is:

{% load navutils_tags %}

{% render_breadcrumbs breadcrumbs %}

The breadcrumbs part of navutils is bundled with two templates, feel free to override them:

• navutils/breadcrumbs.html: the breadcrumbs wrapper

• navutils/crumb.html: used to render each crumb

That’s it !