As you can extend your Wordpress theme by adding actions to the theme’s functions.php, it is safe to say that it is very easy to bloat this file with hundreds of lines of code.

The nasty thing is that the usual advice is to write a function and then add that function as an action by passing the function’s name as a string. That would look something like this:

<?php

// file: functions.php

function my\_theme\_apply\_favicon() {
  // Do stuff like applying a favicon
}

add\_action('wp\_head', 'my\_theme\_apply\_favicon');

?>

Using this method, it is not possible to move logic to other files and all code accumulates into your theme’s functions.php.

Today, however, I have found out there is another way. Apparently, you can also pass a class method method to the add_action hook instead of passing the function’s name as a string:

<?php

add\_action( 'wp-head', array($this, 'my\_theme\_apply\_favicon' ));

?>

This class, then, can be moved to a different file to decrease the size of your functions.php. You then call add_action in the constructor of the class. functions.php only has to instantiate the class.

The end result looks like this:

<?php namespace actions;

// file: actions/apply-favicon.php

class ApplyFavicon {

  public function \_\_construct() {
    add\_action( 'wp-head', array($this, 'my\_theme\_apply\_favicon' ));
  }

  public my\_theme\_apply\_favicon() {
    // Do stuff like applying a favicon
  }

}

?>

<?php

// file: functions.php

// include the ApplyFavicon class file
include 'actions/apply-favicon.php';

// instantiate the class object
new \\actions\\ApplyFavicon();

• child-theme
• php
• wordpress