Act on a taxonomy term that is being assembled before rendering.
The module may add elements to $term->content prior to rendering. The structure of $term->content is a renderable array as expected by drupal_render().
\Drupal\taxonomy\Plugin\Core\Entity\Term $term: The term that is being assembled for rendering.
\Drupal\entity\Plugin\Core\Entity\EntityDisplay $display: The entity_display object holding the display options configured for the term components.
$view_mode: The $view_mode parameter from taxonomy_term_view().
$langcode: The language code used for rendering.
function hook_taxonomy_term_view(\Drupal\taxonomy\Plugin\Core\Entity\Term $term, \Drupal\entity\Plugin\Core\Entity\EntityDisplay $display, $view_mode, $langcode) {
// Only do the extra work if the component is configured to be displayed.
// This assumes a 'mymodule_addition' extra field has been defined for the
// vocabulary in hook_field_extra_fields().
if ($display
->getComponent('mymodule_addition')) {
$term->content['mymodule_addition'] = array(
'#markup' => mymodule_addition($term),
'#theme' => 'mymodule_my_additional_field',
);
}
}