title: Wordpress add_submenu_page function not working
body: <p>I need to create a new menu and a sub menu item for the wordpress administrators. The menu is working fine but the sub menu items ( a duplicate sub menu for the main menu item is being created automatically.. I don't want that ). Both the sub menu items has their href attribute blank. I don't understand what the menu slug is. Please help..</p>
  
  <pre><code>    // create custom plugin settings menu  
         add_action('admin_menu', 'retail_create_menu');
  
         function retail_create_menu() { //create new top-level menu
            add_menu_page('Retailers', 'Retailers', 'administrator', __FILE__, 'generate_retailer_list', 'http://localhost/apsm/wp-content/themes/wp-mediamag/functions/retail.ico'); 
            add_submenu_page( __FILE__, 'Add Retailers', 'Add Retailers', 'administrator', 'add_ratilers.php', 'retailer_submenu_callback');
         }
  </code></pre>
  
  <p>The file are inside a folder in my theme...</p>
  
  <hr>
  
  <p><img src="https://i.stack.imgur.com/ep4b5.png" alt="This is what the menu looks like"></p>