How to add item to $vars[breadcrumb] in Drupal The current breadcrumb only shows 'home'. I would like to update it so it shows 'home>shoes>Tennis Shoe' where 'shoes' is referenced content type(product display) and 'Tennis shoes' the instance(node) title of that content type

Here is how i tried to accomplish this. 

I would push additional items(shoes, tennis shoe) into vars[breadcrumb] at page level(theme_preprocess_page) as following:

function THEME_preprocess_page(&amp;$vars, $hook) {
...
$vars['breadcrumb'][] = '&lt;a href="/shoes"&gt;shoes&lt;a&gt;';
$vars['breadcrumb'][] = '&lt;a href="/shoes/tennis-shoe"&gt;Tennis Shoe&lt;a&gt;';
...
}


And then let my theme_breadcrumb() handle it as it walks through the array:

function THEME_breadcrumb($variables) {
    $breadcrumb = $variables['breadcrumb'];
    if (!empty($breadcrumb)) {
        $breadcrumbs = '&lt;ul class="breadcrumb"&gt;';
        $count = count($breadcrumb) - 1;
        foreach ($breadcrumb as $key =&gt; $value) {
            if ($count != $key) {
                $breadcrumbs .= '&lt;li&gt;' . $value . '&lt;span class="divider"&gt;/&lt;/span&gt;&lt;/li&gt;';
            }
            else{
                $breadcrumbs .= '&lt;li&gt;' . $value . '&lt;/li&gt;';
            }
        }
        $breadcrumbs .= '&lt;/ul&gt;';
        return $breadcrumbs;
    }
}


This doesn't work. Whenever I add the items to the vars['breadcrumb'] in the preprocessor function as showed above, it never goes to 'THEME_breadcrumb', instead displays 'array' text. (apparently, it expects non array at vars['breadcrumb']) How do you manipulate breadcrumbs? Whats wrong with my reasoning? Thank You

Drupal 7, base of boostrap theme
I hope that you have set $breadcrumb in page.tpl.php.
Secondly, you do not need to do it by using theme_preprocess_page. 

Just implement using THEME_breadcrumb like this:

function theme_breadcrumb($variables) {
  $breadcrumb = $variables['breadcrumb'];
  $output = '';
  if ((arg(0) == 'node') &amp;&amp; is_numeric(arg(1)) &amp;&amp; ($node = node_load(arg(1)))) {
    if ($node-&gt;type == 'TYPE NAME') {
      $breadcrumb[] = $node-&gt;title;
    }
  }
  if (!empty($breadcrumb)) {
    $output.= '&lt;div class="breadcrumb"&gt;' . implode(' › ', $breadcrumb) . '&lt;/div&gt;';
  }
  return $output;
}