c++ - How call method from Qt GUI in background worker thread using QThread -

i'm trying add gui in qt code recieving data vrpn server. , need continuously send data server application , call action(method) in interface when receive information.

but have problem endless cycle while (running). found solution use qthread recieving data server, can't figure out how use method qt class in worker when recieve data server.

i tried make worker way, i'm not sure, how call method class when recieve data server (or if it's @ possible/or exist better way):

#include "worker.h"  #include <iostream> #include "vrpn_analog.h"   void vrpn_callback vrpn_analog_callback(void* user_data, vrpn_analogcb analog) {     (int = 0; < analog.num_channel; i++)     {         if (analog.channel[i] > 0)         {                                there want call method nextimage(), have in qt class mainwindow         }      } }  // --- constructor --- worker::worker() {  }  // --- deconstructor --- worker::~worker() {  }  // --- process --- // start processing data. void worker::process() {      /* flag used stop program execution */     bool running = true;      /* vrpn analog object */     vrpn_analog_remote* vrpnanalog;      /* binding of vrpn analog callback */     vrpnanalog = new vrpn_analog_remote("openvibe_vrpn_analog@localhost");     vrpnanalog->register_change_handler(null, vrpn_analog_callback);      /* main loop of program, each vrpn object must called in order process data */     while (running)     {         vrpnanalog->mainloop();     } } 

i'm newbie in using qt i'll grateful help.

add signal callback worker , pass pointer register function (which passed user_data).

void vrpn_callback vrpn_analog_callback(void* user_data, vrpn_analogcb analog) {     (int = 0; < analog.num_channel; i++)     {         if (analog.channel[i] > 0)         {                                worker* worker = std::reinterpret_cast<worker>(user_data);             worker ->callback(i, analog.channel[i]);         }      } }  void worker::process() {      /* flag used stop program execution */     bool running = true;      /* vrpn analog object */     vrpn_analog_remote* vrpnanalog;      /* binding of vrpn analog callback */     vrpnanalog = new vrpn_analog_remote("openvibe_vrpn_analog@localhost");     vrpnanalog->register_change_handler(this, vrpn_analog_callback);//add pointer here      /* main loop of program, each vrpn object must called in order process data */     while (running)     {         vrpnanalog->mainloop();     } } 

then can connect callback signal of worker whatever want independent main window.

connect(worker, &worker::callback, this, &mainwindow::nextimage); 

having said suggest using qtimer set timeout 0 call vrpnanalog->mainloop(); event loop of worker can run once in while.