c++ - How can I connect to FTP server in QT -

i trying connect ftp server got following issue :

qobject::connect: no such slot object::replyfinished in ...\ here program name ......

where mistake? suppose in following code :

///////////////connection.h file////////  class connection : public qobject  {  public:      explicit connection(qobject *parent=0);       connection(qstring uri, qstring usernmae, qstring password);       void ftp_connection();         public slots:          void replyfinished(qnetworkreply *);      private:         qstring uri;         qstring username;         qstring password;         qnetworkaccessmanager *manager;     };      ///////////////connection.cpp file////////    connection::connection(qstring uri, qstring usernmae, qstring password)     {        this->uri=uri;        this->username=usernmae;        this->password=password;     }     void connection::ftp_connection()     {        qurl url(this->uri);        url.setusername(this->username);        url.setpassword(this->password);        url.setport(21);         qnetworkrequest request(url);         manager=new qnetworkaccessmanager(this);        connect(manager,               signal(finished(qnetworkreply*)),               this,               slot(replyfinished(qnetworkreply *)));               manager->get(request);      }       ///////////////main.cpp file////////        int main(int argc, char *argv[])      {         qcoreapplication a(argc, argv);          connection *con=new connection("ftp://192.168.3.62//",                                        "win7",                                        "053253");          con->ftp_connection();          return a.exec();         }