我想尽办法弄明白了。以下是参考代码：

function theme_column_userfield( $defaults ) {  
      $defaults[\'theme-usercolumn-userfield\'] = __(\'fieldname\', \'user-column\');  
      return $defaults;  
}

function theme_custom_column_userfield($value, $column_name, $id) {  
      if( $column_name == \'theme-usercolumn-userfield\' ) {  
            return get_cimyFieldValue($id, \'fieldname\');  
      }  
}

add_action(\'manage_users_custom_column\', \'theme_custom_column_userfield\', 15, 3);
add_filter(\'manage_users_columns\', \'theme_column_userfield\', 15, 1);