以下内容摘自Jetpack，并在管理栏中启用相同的菜单项。

请注意：

标题中的图标是从Jetpack的样式表中提取出来的，脚本是直接打印的，而不是使用wp_enqueue_style 和wp_enqueue_script.add_menu 而不是add_node（根据法典的首选方法）

add_action( \'init\', \'wpse_72564_action_init\' );

function wpse_72564_action_init() 
{
    if ( !has_filter( \'show_admin_bar\', \'__return_true\' ) && !is_user_logged_in() )
        return;
    add_action( \'admin_bar_menu\', \'wpse_72564_admin_bar_menu\', 120 );
    add_action( \'wp_head\', \'wpse_72564_styles_and_scripts\' );
    add_action( \'admin_head\', \'wpse_72564_styles_and_scripts\' );
}

function wpse_72564_admin_bar_menu() 
{
    global $wp_admin_bar, $current_blog;

    if ( !is_object( $wp_admin_bar ) )
        return;

    $classes = \'wpse-loading wpse-read\';
    $wp_admin_bar->add_menu( array(
        \'id\'     => \'wpse_menu\',
        \'title\'  => \'<span id="wpse-admin-bar-menu" class="\' . esc_attr( $classes ) . \'">
                <span class="noticon noticon-notification" /></span>
                </span>\',
        \'meta\'   => array(
            \'html\'  => \'<div id="wpse-notes-panel" style="display:none"><div class="wpse-notes-panel-header"><span class="wpse-notes-header">\' . __(\'Notifications\', \'jetpack\') . \'</span><span class="wpse-notes-panel-link"></span></div></div>\',
            \'class\' => \'menupop\',
        ),
        \'parent\' => \'top-secondary\',
    ) );

}
function wpse_72564_styles_and_scripts()
{
    ?>
    <script language="javascript" type="text/javascript">
        jQuery(document).ready(function($) {
            $(\'#wpse-admin-bar-menu\').click(function() 
            {
               $(\'#wpse-notes-panel\').toggle();
            });
        });
    </script>   
    <?php
}