django-lineage 0.1

Simplify navigation styling using the isanscestor template tag

Django Lineage
==============

Handling which navigation element is active in a particular template can get a
bit ugly. Often, creating template blocks to drop an "active" class on a
particular tab or list element.

Lineage makes things neater by defining your conditions once, and it
looks like this:

{% load lineage %}

<ul>
<li {% ifanscestor 'home' %}class="active"{% endifanscestor %}">
<a href="{% url 'home' %}">Home</a>
</li>
<li {% ifanscestor 'blog' %}class="active"{% endifanscestor %}">
<a href="{% url 'blog' %}">Blog</a>
</li>
<li {% ifanscestor 'about' %}class="active"{% endifanscestor %}">
<a href="{% url 'about' %}">About</a>
</li>
</ul>

Whereas before we might have had the following:

`base.html` template:

<ul>
<li class="{% block home_class %}{% endblock %}">
<a href="{% url 'home' %}">Home</a>
</li>
<li class="{% block blog_class %}{% endblock %}">
<a href="{% url 'blog' %}">Blog</a>
</li>
<li class="{% block about_class %}{% endblock %}">
<a href="{% url 'about' %}">About</a>
</li>
</ul>

`home.html` template:

{% extends 'base.html' %}
{% block home_class %}active{% endblock %}

`blog.html` template:

{% extends 'base.html' %}
{% block blog_class %}active{% endblock %}

`about.html` template:

{% extends 'base.html' %}
{% block about_class %}active{% endblock %}

Installation
------------

Install using pip:

pip install django-lineage

Add to INSTALLED_APPS in your Django settings file:

INSTALLED_APPS = (
'lineage',
)

Usage
-----

First, load Lineage's template library:

{% extends 'base.html'}
{% load lineage %}

Lineage provides a single template tag `ifanscestor` which acts much like the
`if`/`endif` template tag:

{% ifanscestor '/arbitrary/path/' %}
This content is only displayed if the provided
path matches the start of the current URL
{% endifanscestor %}

`ifanscestor` can also handle a variable:

{% ifanscestor some_variable %}{% endifanscestor %}

Or even the same arguments used by the `url` template tag to return an absolute
path given a view function or named pattern.

{% ifanscestor 'core:model_detail' model.pk %}{% endifanscestor %}