Yii 1.1: Simplified meta tags

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If we want to set meta tags on a per page (controller-action) basis, we may use the clientScript application component.

Controller

<?php
 
class ExampleController extends CController
{
 
  public function actionIndex()
  {
 
    Yii::app()->clientScript->registerMetaTag('This is an example', 'description');
 
    $this->render('example');
 
  }
 
}
 
?>

This will insert the description meta tag automatically into the layout when the render() function gets called.

Another solution would be to use a parent controller with the property $pageDescription. That way we don't have to make a function-call to set the description. Instead, we can easily modify the description inside of the controller. In the layout-file we'll simply echo the meta tag (if defined).

Parent-Controller

<?php
 
class ParentController extends CController
{
 
  public $pageDescription;
 
}
 
?>

Controller

<?php
 
class ExampleController extends ParentController
{
 
  public function actionIndex()
  {
 
    $this->pageDescription = 'This is an example';
 
    $this->render('example');
 
  }
 
}
 
?>

Layout

<html>
<head>
<?php
 
if (!empty($this->pageDescription))
{
  echo '<meta name="description" content="' . $this->pageDescription . '" />';
}
 
?>
<title>Example</title>
</head>
 
<body>
 
</body>
</html>

As you can see, the second solution is probably better to work with because we can directly access $pageDescription and won't have to call an ugly long function every time. On the other hand, we have now additional php-code in the layout. Well that's not bad at all, but it could lead to problems.

What if we have 10 different layouts? What if we use several themes? In each of these files we would've to insert that snippet. Now let's think instead of a single string (the description), we would implement the same functionality for several rss-feed meta tags (an array). That would mean we have to do a foreach inside of the layout(s).

For a more flexible solution, we extend CController with a custom function.

<?php
 
class ExtendedCController extends CController
{
 
    public function render($view, $data = null, $return = false)
    {
        if ($this->beforeRender())
        {
            parent::render($view, $data, $return);
        }
    }
 
    public function beforeRender()
    {
        return true;
    }
 
}
 
?>

The parent-controller will make use of our extended CController and the special function.

<?php
 
class ParentController extends ExtendedCController
{
 
    public $pageDescription;
 
    public function beforeRender()
    {
 
        if (!empty($this->pageDescription))
        {
            Yii::app()->clientScript->registerMetaTag($this->pageDescription, 'description');
        }
 
        return true;
 
    }
 
}
 
?>

The actual controller remains the same (like in the second solution).

<?php
 
class ExampleController extends ParentController
{
 
  public function actionIndex()
  {
 
    $this->pageDescription = 'This is an example';
 
    $this->render('example');
 
  }
 
}
 
?>

When the render() function gets called, ExtendedCController will first execute the custom beforeRender() function in our parent-controller to insert the meta tag and after that it will call the original CController::render() function.

That means with this solution we can access the $pageDescription property inside of the controller and we don't have to add any special code to the layout. Of course this solution comes in handy especially for things like the already noted rss-feeds.

Think about this:

$this->pageFeeds[] = 'http://example.com/feeds/recent.xml';
$this->pageFeeds[] = 'http://example.com/feeds/popular.xml';

I hope you enjoyed the read. Feel free to share your thoughts - thank you.

Tip: Since the two classes ParentController and ExtendedCController are no real controllers (they only function as parent-classes), you have to put them into the components folder (eg protected/components).

Total 4 comments

#15681 report it
omeraslam at 2013/12/06 07:50am
omer aslam

can yo please tell what values are used for the options parameter in registerLinkTag().

#14599 report it
Cozumel at 2013/08/27 04:19am
Possible Bug?

In Yii 1.1.14 (maybe earlier too) this duplicates the tags, the way around this is to specify an id:

Yii::app()->clientScript->registerMetaTag('my description', 'description', null, array(), 'uniqueid');
#14246 report it
Csar at 2013/07/30 02:05am
I got duplicated Meta Tag

#3002 report it
stutteringp0et at 2011/03/07 10:10am
So, description, keywords, feeds and more

It looks like your solution could be adapted to cover the whole array of meta information commonly included in the head.

Additionally, a per-controller or even per-view favicon could be set.

Yii::app()->clientScript->registerLinkTag(
    'shortcut icon',
    'image/vnd.microsoft.icon',
    'path/to/favicon.ico'
);

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  • Written by: Y!!
  • Category: Tutorials
  • Yii Version: 1.1
  • Votes: +13
  • Viewed: 29,808 times
  • Created on: Nov 6, 2009
  • Last updated: Jun 4, 2010