For all admin pages and front end pages except individual post edit screens (wp-admin/post.php), ‘wp’ is the most reliable hook for getting the global values. http://phpxref.ftwr.co.uk/wordpress/nav.html?wp-includes/class-wp.php.source.html#l486 You can see there that it fires immediately after WP::main() fires WP::register_globals(). The problem with using things like post_results and get_posts is that it will run every time you … Read more
You are using it wrong. add_action: attachs a function to an action hook. In your code, you are attaching alter_item funtion to admin_menu action hook. So, when admin_menu action happens, alter_item function is executed. According to codex, no parameters are passed to functions attached to admin_menu. So, the parameters your are trying to use in … Read more
As long as hooks don’t have anything hooked to them they are no-ops, that is do nearly nothing and have no considerable effect on runtime. It gets quite different when things are hooked and there are a lot of calls. Since you talk about customizing strings the good example would be gettext hook in core. … Read more
It is possible for action hooks to be provided without being used, which is what’s happening here. woocommerce_before_checkout_process and woocommerce_checkout_process are hooks provided by WooCommerce, but WooCommerce does not itself attach callback functions to either of these hooks. They are provided to allow plugins and themes to run code at the time that the respective … Read more
Ajax in WordPress works by sending an HTTP post to /wp-admin/admin-ajax.php (by default) that then fires the corresponding hook. So, you attach some jquery to an event triggered by your delete button, which then posts to admin-ajax.php, which has an action, say, delete_my_options(), which actually runs the php to delete. Then, you have a function, … Read more
Like @milo pointed out in the comment, checking if the post meta exists is the easiest way to achieve what you want – like this: add_action(‘publish_post’, ‘wpse120996_add_custom_field_automatically’); function wpse120996_add_custom_field_automatically($post_id) { global $wpdb; $votes_count = get_post_meta($post_id, ‘votes_count’, true); if( empty( $votes_count ) && ! wp_is_post_revision( $post_id ) ) { update_post_meta($post_id, ‘votes_count’, ‘0’); } } → On … Read more
This will do the trick! add_action(‘trash_post’,’my_trash_post_function’,1,1); function my_trash_post_function($post_id){ if(!did_action(‘trash_post’)){ // do stuff } } Here we add the function, and to prevent the hook from executing more than once using did_action: http://codex.wordpress.org/Function_Reference/did_action As always, these kinds of hooks take the form {post_status}_{post_type}, so trash_post, trash_page, trash_customposttype, publish_page etc
You need a second form with admin_url(‘admin-post.php’) as form action. Then you can hook into admin_post_custom_action to execute your action. Sample code: add_action( ‘admin_post_wpse_79898’, ‘wpse_79898_test’ ); function wpse_79898_test() { if ( isset ( $_GET[‘test’] ) ) echo esc_html( $_GET[‘test’] ); die( __FUNCTION__ ); } In your settings page: <form action=”<?php echo admin_url( ‘admin-post.php’ ); ?>”> … Read more
At the beginning of wp_insert_post, the function that saves/updates a post, there is a filter called wp_insert_post_empty_content. By default this filter checks whether the title, editor, and excerpt fields are all empty, in which case the save process will be halted. However, since all the fields to be saved are passed to this filter, you … Read more
The user roles and capabilities are saved in the database so once you have you have used add_role() its saved and then next load WordPress will know that role just like the built in roles. Now if you look at the function add_role() more specifically at line 141 you will see that it only saves … Read more