How to get child terms based on parent terms between two different taxonomies

Question

I have created two vocabulary

1. Program
2. Topics

I want to load the topics based on the program selection.

It looks like category and subcategory.

I created some program like java, .net, PHP and I created some topics like session (php), inheritance(java), cookie(php).

So now I want to list all the topics which are coming under a particular program.

Can you tell me which drupal function used to get all the terms under parent terms.?

Note: taxonomy_get_children not working because I am using two vocabularies

Answer 1

You'll need to load your content's term references and then load those term entities so you can follow your chain of taxonomy terms. There's many ways to do that; taxonomy_term_load_multiple() is one such function.

$tids = array();

// @TODO: Use the $nid that corresponds with your node 
// @TODO: Replace field_program & field_topic with your taxonomy ref field name
$node = node_load($nid);
foreach ($node->field_programs[LANGUAGE_NONE] as $term) {
  $tids[] = $term['tid'];
}
$programs = taxonomy_term_load_multiple($tids);

// @TODO: Iterate over $programs and retrieve 
// topic tid references from $program->field_topic[LANGUAGE_NONE]

Answer 2

You can add code in template.php as theme_preprocess_page()
if(arg(0) == 'taxonomy' && arg(1) == 'term') { $tid = (int)arg(2); $term = taxonomy_term_load($tid); $arrTermId = taxonomy_get_children($tid); $arrData = taxonomy_select_nodes(array_keys($arrTermId), $pager = TRUE, $limit = FALSE, $order = array('t.sticky' => 'DESC', 't.created' => 'DESC')); $arrContent = node_load_multiple($arrData, $conditions = array(), $reset = FALSE); print_r($arrContent); }

In $arrContent you will get values of all the nodes.