请尝试以下代码，

function remove_menuitems_from_admin_bar() {
    global $wp_admin_bar;
    $wp_admin_bar->remove_menu(\'wp-logo\');
    $wp_admin_bar->remove_menu(\'user-info\');
    $wp_admin_bar->remove_menu(\'site-name\');
    $wp_admin_bar->remove_menu(\'dashboard\');
    $wp_admin_bar->remove_menu(\'edit-profile\', \'user-actions\');
    $wp_admin_bar->remove_menu(\'my-account\');

    $user_id = get_current_user_id();
    $current_user = wp_get_current_user();
    if (!$user_id)
        return;

    $avatar = get_avatar($user_id, 26);       
    $howdy = sprintf(__(\'Howdy, %s\'), \'<span class="display-name">\' . $current_user->display_name . \'</span>\');
    $class = empty($avatar) ? \'\' : \'with-avatar\';

    $wp_admin_bar->add_menu(array(
        \'id\' => \'my-account\',
        \'parent\' => \'top-secondary\',
        \'title\' => $howdy . $avatar,
        \'meta\' => array(
            \'class\' => $class,
        ),
    ));
}
add_action(\'wp_before_admin_bar_render\', \'remove_menuitems_from_admin_bar\');