通过插件在管理页面上加载自定义js文件

Question

I'm new to the world of Wordpress and I just started developing my first plugin. When it's activated it should load one javascript file to wp-admin/post-new.php (Add new post) page.

Here is how I tried to do this:

Plugin

class WP_Blog_Customizer{
    function __construct() {
        add_action( 'wp_enqueue_scripts', array($this, 'load_dependencies') ); 
        register_activation_hook( __FILE__, array( $this, 'wpa_install' ) );
        register_deactivation_hook( __FILE__, array( $this, 'wpa_uninstall' ) );
    }
    public function load_dependencies(){
        wp_enqueue_script('blog-customizer', plugins_url('js/blog-customizer.js', __FILE__),array('jquery'),'1.0.0', true);
    }
}
new WP_Blog_Customizer();

wp-admin/post-new.php

if(is_plugin_active( 'blog-customizer/blog-customizer.php' )){
        $plugin = new WP_Blog_Customizer();
}

Shouldn't this add_action( 'wp_enqueue_scripts', array($this, 'load_dependencies') ); from the __construct of my plugin class include this js file?

Note

This js file is located under the js folder in my plugin's folder, so the path is correct.

Can anyone tell me why this is not working, and how to make it work?

Answer 1

For loading scripts in admin side we have to use admin_enqueue_scripts hook. So something like this should do the job:

class WP_Blog_Customizer{
    function __construct() {
        add_action( 'admin_enqueue_scripts', array($this, 'load_dependencies') ); 
        //...other constructor things
    }
    public function load_dependencies( $hook ){
        if ( $hook == 'post-new.php' ) { // for loading script also on post edit screen use ( $hook == 'post-new.php' || $hook == 'post.php' )
            wp_enqueue_script('blog-customizer', plugins_url('js/blog-customizer.js', __FILE__),array('jquery'),'1.0.0', true);
        }
    }
}
new WP_Blog_Customizer();