
        'my-plugin-main',
    'my_plugin_main_page'
);

add_submenu_page(
    'my_plugin_main_page',
    'My Plugin Subpage',
    'Subpage',
    'manage_options',
    'my-plugin-subpage',
    'my_plugin_subpage'
);
        ]]>


        __FILE__,
    'my_plugin_main_page'
);

add_submenu_page(
    __FILE__ . 'my_plugin_main_page',
    'My Plugin Subpage',
    'Subpage',
    'manage_options',
    'my-plugin-subpage',
    'my_plugin_subpage'
);
        ]]>