| 5 common.inc | drupal_set_html_head($data = NULL) |
| 6 common.inc | drupal_set_html_head($data = NULL) |
Add output to the head tag of the HTML page.
This function can be called as long the headers aren't sent.
File
- includes/
common.inc, line 116 - Common functions that many Drupal modules will need to reference.
Code
<?php
function drupal_set_html_head($data = NULL) {
static $stored_head = '';
if (!is_null($data)) {
$stored_head .= $data . "\n";
}
return $stored_head;
}
?>
Comments
Beware when using this to set
Beware when using this to set an external js file call in D6, eg:
drupal_set_html_head('<script type="text/javascript" src="http://maps.google.co.uk/maps/api/js?sensor=false" />');If you don't include a full script closing tag (ie
</script>), it will break in Firefox (and possibly other browsers, webkit-based ones seem fine). The tag will fail to close, and will wipe out any other headers up to the next available</script>tag. This usually results in all your css files failing to load, plus the next fully-tagged js file. So use this form instead:drupal_set_html_head('<script type="text/javascript" src="http://maps.google.co.uk/maps/api/js?sensor=false"></script>');This applies up to and including Drupal 6.16. You can overcome it in D7 with the new external option in drupal_add_js.
Changed in Drupal 7
I would like to note that this has become drupal_add_html_head() in Drupal 7.
drupal_add_html_head
Link to Drupal 7 drupal_add_html_head
Note if used in template_preprocess_page()
If you are calling drupal_set_html_head() in template_preprocess_page() you need to do this after:
$vars['head'] = drupal_get_html_head();to make the changes have any effect in your page.tpl.php file.
Clarification & example
This means, you first make your call to drupal_set_html_head() in the THEMENAME_prepreprocess_page() function in your theme's template.php file, then add the aforementioned snippet. This is necessary so the value of the $head variable in page.tpl.php is updated from what it was originally set to in template_preprocess_page().
For example,
<?phpfunction mytheme_preprocess_page(&$vars, $hook) {
// Add Google Webmaster Tools verification to homepage.
if(drupal_is_front_page()) {
drupal_set_html_head('<meta name="google-site-verification" content="[string from https://www.google.com/webmasters/verification/verification]" />');
$vars['head'] = drupal_get_html_head();
}
}
?>
one more little tiny change
I use the meta tags module so this code actually killed all my meta tags. To get around this I made changed the above suggestion to this:
<?php
function mytheme_preprocess_page(&$vars, $hook) {
// Add Google Webmaster Tools verification to homepage.
if(drupal_is_front_page()) {
drupal_set_html_head('<meta name="google-site-verification" content="[string from https://www.google.com/webmasters/verification/verification]" />');
//previous version, replacing $vars['head']
//$vars['head'] = drupal_get_html_head();
//suggested replacement, keeping old head tags
$vars['head'] .= drupal_get_html_head();
}
}
?>
For now this seems to work fine. I don't really understand what I'm doing though so a word of confidence from a guru would be nice.
Simply add it to template_preprocess_page
You don't need to use this function in template_preprocess_page, you can simply add it like so.
<?phpfunction mytheme_preprocess_page(&$vars, $hook) {
// Add Google Webmaster Tools verification to homepage.
if(drupal_is_front_page()) {
$vars['head'] .= '<meta name="google-site-verification" content="[string from https://www.google.com/webmasters/verification/verification]" />');
}
}
?>
Placement in relation to other scripts warning
When using this from a module with hook_init(), your inserted script or whatever else you want to put into the head will be prepended to the exisitng drupal head, not appended.
Therefore, anything subsequently added to the page by other modules and such could potentially override your setting.
(E.g. if you try to set the title, or if you try to override jquery or something..)