OnContentPrepare called with JCategoryNode

From Joomla! Documentation

Executing a category blog view the event function onContentPrepare of content plugins: public function onContentPrepare($context, &$article, &$params, $limitstart)

is now called more than once per each article included in the category blog and it receives a quite unexpected JCategoryNode object as $article reference.

Called once for each article included in the category blog view but even for each category link showed in that view thus receiving a JCategoryNode object as $article parameter. This leads to errors when a content plugin deals for example with $article->catid that is not an available property in JCategoryNode

Errors reported[edit]

If your content plugin does not validate properly the $context of the caller it may generate PHP strict notices, for example if it work with the $article->catid property. Indeed the JCategoryNode object has not a catid property like the stdClass object referring to the real object that represents the article. If the plugin validates the context in a generic way such as the following this won't be enough anymore: preg_match('/com_content/i', $context);

Versions affected[edit]

General Information

This pertains only to Joomla! version(s): 3.7.0

What is the cause[edit]

This happens because of the new feature of custom fields introduced in Joomla 3.7

How to fix[edit]

Carefully validate the context of the plugin call, for example:

if($context == 'com_content.categories') { return; }


if(!$article instanceof stdClass) { return; }

Update content plugins accordingly.