Change layout of a view 'page display' based on number of grouping field occurences

Question

Sorry about that rather specific title: hopefully my question will clarify itself with the following:

What data is on the table to work with

I have a View (page display) that lists nodes based on the main categories "Fruit" and "Veggies"
So I have two pages: 1 at www.mysite.com/fruit and the other www.mysite.com/veggies

• arg(0) is being used as a contextual filter to get the right nodes on both those pages.
• I'm grouping my nodes (grouping field dropdown in Style options) based on the taxonomy term they belong to (eg for "Fruit" > sweet and sour) to reflect their hierarchical place in the taxonomy structure (see below)

fruit
-- sweet(taxonomy term)
-- -- banana node
-- -- melon node
-- sour(taxonomy term)
-- -- lemon node

veggies
-- red (taxonomy term)
-- -- paprika node
-- -- onion node

What I would like achieve

I would like to be able to add different styling to a page that has only 1 main category (like the veggies - categorypage -> we only have the "red" subcateg there) as opposed to a page that has 2 or more main categories (like the fruit - categorypage -> we have 2 subcategs there: "sweet" and "sour")

What I have uptil now (it's working but I need to clean up my act/code)

As stated ... this already functions , but I would love to know:

• if I followed Drupal protocols.
• if there are better ways (more performant, cleaner code, easier)

I've got this in my template.php

/* Helper function so I can reach my specific display in the preprocess hook below*/
function <themename>_preprocess_views_view(&$vars) {
  if (isset($vars['view']->name)) {
    $function = __FUNCTION__ . '__' . $vars['view']->name . '__' . $vars['view']->current_display;

    if (function_exists($function)) {
     $function($vars);
    }
  }

// This is where I inject a custom CSS file in the case where I've got only 1 Main category (as explained above)
function <themename>_preprocess_views_view__need__page(&$vars) {
  $tidArr = $vars['view']->field['term_node_tid']->view->field['term_node_tid']->items;
  $terms = array();
  foreach ($tidArr as $key=>$tids) {
    $terms[] =  current(reset($tids)); 
  }
  $uniqueTids = count(array_unique($terms));
  if($uniqueTids < 2) {
      drupal_add_css(path_to_theme() .'/css/my_custom_css.css');
  }

}

Disclaimer: Heavy question , I know ... but hopefully clear enough so you can all understand what is going on , and what I'm trying to achieve.
Understand that I'm happy I got it working , but I would be even more happy if I could do it the Drupal "way" and have my code as lean and mean as possible.
thanx for taking the time. }

Answer 1

I think what you are trying to drupalize/ise this into is something along the lines of:

function YOURTHEME_preprocess_views_view(&$vars) {

  $view=$vars['view'];

  if (empty($view)) {
    watchdog('YOURTHEME', 'Rut roh Rastro....');
    return;
  }

  switch ($view->name) {

     case 'need':

        if ($view->current_display=='page') {

          $tid_arr = $view->field['term_node_tid']->view->field['term_node_tid']->items;
          $terms = array_keys($tid_arr);
          $number_tids = count($terms);

          if ($number_tids == 1) {
            drupal_add_css(path_to_theme() . '/css/my_custom_css.css');
          }

        }

        break;

     // any other views here

  }

}

with my basic comment being that you switch on the View's name in the preprocess function and do all your work in there instead of going out into another function.