When Jeff wrote about plugin deactivation breaking your blog, Aaron and I wrote in the comments of a few solutions to prevent plugin issues with themes. Within this post I will present several techniques plugin and theme authors can take in order to prevent deactivation issues. Method 1: function_exists In this example, let’s assume we have a function named related_posts. When in a theme, we could use this code to call the function if only it exists. <?php if (function_exists("related_posts")) { related_posts(); } ?> The PHP function_exists checks for the existence of the function, and if it does exist, it calls the function. Method 2: function_exists and Actions Using the same function name, the theme author could add some code into their functions.php file and use an action and function_exists combination. if (function_exists('related_posts')) { add_action('my_related_posts', 'related_posts'); } In the above example, we create a new action called my_related_posts. The end […]