class IBLikeable {

    function __construct() {
        // ... initialize class properties
        add_action( 'admin_print_scripts', array( $this, 'enqueue_admin' ) );
    }

    function register_admin_menus() {

        $hook = add_options_page('ibLikeable Settings', 'ibLikeable', 'manage_options', $this->prefix, array( $this, 'render_settings_page' ) );
        $this->settings_hook = $hook;

        add_action( 'admin_print_scripts-' . $hook, array( $this, 'enqueue_admin') );

    }
    // ... more code ...

    function enqueue_admin() {
        $screen = get_current_screen();

        if( $screen->id == $this->settings_hook ) {
            wp_register_style($this->prefix . '-settings', $this->url . 'css/settings_page.css' );
            wp_enqueue_style( $this->prefix . '-settings');
            wp_register_script( $this->prefix . '-settings-js', $this->url . 'js/settings_page.js', array('jQuery') );
            wp_enqueue_script($this->prefix . '-settings-js');
        }
    }
}