How to add custom javascript to WordPress Admin?

Question

I want to add some custom jquery code to the Edit Post page, something really simple like showing a div when someone presses Publish.

The only restriction is that I want to achieve this through the use of a plugin, not hacking the admin template files.

I've tried echoing some script tags using some actions but it doesn't seem to be the way.

Answer 1

Use the admin_enqueue_scripts action and thewp_enqueue_script method to add custom scripts to the admin interface.

This assumes that you have myscript.js in your plugin folder. Change accordingly. The my_custom_script handle should be unique for your module and script.

function my_enqueue($hook) {
    // Only add to the edit.php admin page.
    // See WP docs.
    if ('edit.php' !== $hook) {
        return;
    }
    wp_enqueue_script('my_custom_script', plugin_dir_url(__FILE__) . '/myscript.js');
}

add_action('admin_enqueue_scripts', 'my_enqueue');

Answer 2

There is a snippet for Your functions.php file :

function custom_admin_js() {
    $url = get_bloginfo('template_directory') . '/js/wp-admin.js';
    echo '"<script type="text/javascript" src="'. $url . '"></script>"';
}
add_action('admin_footer', 'custom_admin_js');

Works fine on Wordpress 3.2.1.

Answer 3

<?php
function add_jquery_data() {
    global $parent_file;

    if ( isset( $_GET['action'] ) && $_GET['action'] == 'edit' && isset( $_GET['post'] ) && $parent_file == 'edit.php') {
    // Do some stuff.
    }
}

add_filter('admin_head', 'add_jquery_data');

?>

Answer 4

admin_enqueue_scripts and wp_enqueue_script are the preferred way to add javascript files to the dashboard.

// I'm using an anonymous function for brevity.
add_action( 'admin_enqueue_scripts', function() {
    wp_enqueue_script( 'handle', plugin_dir_url( __FILE__ ) . '/script.js' );
} );

If you want to output the javascript using your PHP function however, wp_add_inline_script doesn't seem to work. Instead, you can use admin_print_scripts to directly echo out the script, including the script tags themselves. Just ensure to set the priority high so that it loads after any required libraries, such as jQuery .

add_action( 'admin_print_scripts', function() {
    // I'm using NOWDOC notation to allow line breaks and unescaped quotation marks.
    echo <<<'EOT'
<script type="text/javascript">
jQuery(function($){
    // Do stuff here.
});
</script>
EOT;
}, PHP_INT_MAX );

Answer 5

If you want to get fancy and filter where you want to load the file or not, best to use get_current_screen .

function myproject_admin_enqueue() {

    $screen = get_current_screen();

    // load on the NEW and EDIT screens of all post types
    if ( 'post' === $screen->base ) {
        wp_enqueue_script('my_custom_script', plugin_dir_url( __FILE__ ) . 'all-admin.js');
    }

    // load on the NEW and EDIT screens of one post type
    if ( 'post' === $screen->base && 'myposttype' === $screen->post_type ) {
        wp_enqueue_script('my_custom_script', plugin_dir_url( __FILE__ ) . 'mypostype-admin.js');
    }

    // load only when adding a NEW post, not when editing an existing one.
    if ( 'post' === $screen->base && 'add' === $screen->action ) {
        wp_enqueue_script('my_custom_script', plugin_dir_url( __FILE__ ) . 'new-admin.js');
    }

}
add_action('admin_enqueue_scripts', 'myproject_admin_enqueue');

Answer 6

Directly adding wp_enqueue_script to your code doesn't include the script in new versions of Wordpress (5.0 above). The better way is to register the script with wp_register_script first to create a handle and then enqueue that handle.

function custom_script_in_admin($hook) {
    if ('edit.php' !== $hook) {
        return;
    }
    wp_register_script( 'custom_handle_name',plugin_dir_url( __FILE__ ) . '/script.js', '',true );
    wp_enqueue_script('custom_handle_name');
}

add_action('admin_enqueue_scripts', 'custom_script_in_admin');

Answer 7

Somehow the accepted answer didn't work for me. Here is another solution I didn't found in the answers and this is what did it for me, WP 5.x, adding some css and js for my backend...

function suedsicht_theme_add_editor_assets() {
  wp_enqueue_style( 'custom-gutenberg-stylesheet', get_template_directory_uri() . '/css/custom-editor-style.css', array(), wp_get_theme()->get( 'Version' ), 'all' );
  wp_enqueue_script('suedsicht-admin-js', get_template_directory_uri() . '/js/admin.js');
}
add_action( 'enqueue_block_editor_assets', 'suedsicht_theme_add_editor_assets' );

Answer 8

By using the admin enqueue script hook you can easily add the script file for the admin panel.

function custom_admin_js() {

wp_enqueue_script( 'custom_wp_admin_js', get_template_directory_uri() . '/new-assets/js/admin_section.js', false, '1.0.0' );
wp_enqueue_script( 'custom_wp_admin_js' );
}

add_action('admin_enqueue_scripts', 'custom_admin_js');