What is WordPress Hook: attachment_icon
The attachment_icon hook in WordPress is used to modify or add icons to file attachments in the media library. It allows developers to customize the icons displayed for different file types.
Understanding the Hook: attachment_icon
The attachment_icon hook is located within the wp-includes/post.php file in WordPress. It is called within the get_attachment_icon function, which is responsible for retrieving the icon for a specific attachment based on its file type.
Hook Parameters (if applicable): attachment_icon
The attachment_icon hook accepts two parameters: $icon and $mime. The $icon parameter is the URL of the default icon for the attachment, while the $mime parameter is the MIME type of the attachment file.
Hook Doesn’t Work: attachment_icon
If the attachment_icon hook doesn’t work as expected, it may be due to incorrect usage of the hook or conflicts with other functions or plugins. To troubleshoot, developers should check for any errors in their code and ensure that the hook is being called in the correct location within their theme or plugin files.
Best Practices & Usage Notes (if applicable): attachment_icon
When using the attachment_icon hook, developers should be aware that it may not work for all file types, especially custom file types that are not natively supported by WordPress. It is also important to consider the performance implications of adding custom icons for attachments, as it may impact the loading time of the media library.
Usage Example: attachment_icon
“`php
function custom_attachment_icon($icon, $mime) {
if ($mime == ‘application/pdf’) {
$icon = ‘https://example.com/pdf-icon.png’;
}
return $icon;
}
add_filter(‘attachment_icon’, ‘custom_attachment_icon’, 10, 2);
“`