Templating

By default, a proxy object to current_breadcrumbs is added to your Jinja2 context as breadcrumbs to help you with creating navigation bar. For example:

<div>
{%- for breadcrumb in breadcrumbs -%}
    <a href="{{ breadcrumb.url }}">{{ breadcrumb.text }}</a>
    {{ '/' if not loop.last }}
{%- endfor -%}
</div>

Blueprint Support

The most import part of an modular Flask application is Blueprint. You can create one for your application somewhere in your code and decorate your view function, like this:

from flask import Blueprint
from flask.ext import breadcrumbs

bp_account = Blueprint('account', __name__, url_prefix='/account')

@bp_account.route('/')
@breadcrumbs.register_breadcrumb(bp_account, '.', 'Your account')
def index():
    pass

Default breadcrumb root

Sometimes you want to combine multiple blueprints and organize the navigation to certain hierarchy using function default_breadcrumb_root().

from flask import Blueprint
from flask.ext import breadcrumbs

bp_social = Blueprint('social', __name__, url_prefix='/social')
breadcrumbs.default_breadcrumb_root(bp_social, '.account')

@bp_account.route('/list')
@breadcrumbs.register_breadcrumb(bp_social, '.list', 'Social networks')
def list():
    pass

As a result of this, your current_breadcrumbs object with contain list with 3 items during processing request for /social/list.

>>> from example import app
>>> from flask.ext import breadcrumbs
>>> import account
>>> import social
>>> app.register_blueprint(account.bp_account)
>>> app.register_blueprint(social.bp_social)
>>> with app.test_client() as c:
...     c.get('/social/list')
...     assert map(lambda x: x.url,
...         list(breadcrumbs.current_breadcrumbs)) == \
...         ['/', '/account/', '/social/list']