正常抓是不走代理的，需要给dio对象配置代理：

Dio dio = Dio();
    
(dio.httpClientAdapter as DefaultHttpClientAdapter).onHttpClientCreate = (HttpClient client) {
  client.findProxy = (uri) {
    return "PROXY localhost:8888";
  };
};

localhost mac电脑可以用ifconfig命令看，或者直接在Charles——>Help——>Local IP Address