How can I hide entries depending on which category they are associated with?

Question

Right now, I have a staff profile page. Each person on the page has a category association (professional, leadership, student). When the students graduate, I want to add an 'alumni' category to their entry, and have them stop showing up on the active page. Right now I have student and alumni associated with the particular entry, and I want to hide all entries with the alumni category. Any idea how to go about this?

{% set leaderGroup = craft.categories.group('staffHierarchy').slug('leadership') %}
{% set leader = craft.entries.section('people').relatedTo(leaderGroup) %}
{% set staffGroup = craft.categories.group('staffHierarchy').slug('student') %}
{% set staff = craft.entries.section('people').relatedTo(staffGroup) %}

Answer 1

The search parameter will help you do this really elegantly.

In the code below I've called the category field categoryField, but you'll have to swap that to suit your site.

{# Get current students (students who aren't also in the alumni category) #}
{% set currentStudents = craft.entries.section('people').search('categoryField:student -categoryField:alumni') %}

{% for student in currentStudents %}
    {# Output your students here #}
{% endfor %}

This is basically asking Craft to respond with the entries that have the categoryField including student but not (indicated by the - before) including alumni.

You could probably also streamline the other bits of your code using this method.

I've tested this as working on Craft 2.5.2757

Hope that helps!

Answer 2

I wouldn't want to rely on up-to-date search indexes for this and would rather make use of the relatedTo parameter instead.

Unfortunatelly it isn't very straightforward to exclude a category (e.g. relatedTo('not 24') doesn't work), but there's a common workaround many Craft devs use in cases like this: collect IDs and query against them (→ see related questions: Get entries NOT related to categories or How can I select users that are not members of any user groups?).

{% set leadCategory = craft.categories.group('staffHierarchy').slug('leadership').first() %}
{% set studCategory = craft.categories.group('staffHierarchy').slug('student').first() %}

{% set alumniCategory = craft.categories.group('staffHierarchy').slug('alumni').first() %}

{% set alumniGroupIds = craft.entries({
    section: 'people',
    relatedTo: alumniCategory,
    limit: null
}).ids() %}

{% set idParam = 'and, not ' ~ alumniGroupIds|join(', not ') %}

{% set leadGroup = craft.entries({
    section: 'people',
    id: idParam,
    relatedTo: leadCategory,
    limit: null
}) %}

{% set studGroup = craft.entries({
    section: 'people',
    id: idParam,
    relatedTo: studCategory,
    limit: null
}) %}