How can I move my normal c++ main() function code to qt main function?

Question

I have created small normal c++ code to test in raspberry pi which is working perfectly fine on the terminal.Now I want to write it down in qt, the problem here I am facing is I can able to move my functions inside the main function into another function. This is the code: rotary_encoder.cpp

#include <iostream>

#include <pigpio.h>

#include "rotary_encoder.hpp"

void re_decoder::_pulse(int gpio, int level, uint32_t tick)
{
  if (gpio == mygpioA) levA = level; else levB = level;

   if (gpio != lastGpio) /* debounce */
   {
     lastGpio = gpio;

     if ((gpio == mygpioA) && (level == 1))
     {
      if (levB) (mycallback)(1);
  }
  else if ((gpio == mygpioB) && (level == 1))
  {
     if (levA) (mycallback)(-1);
  }
 }
}

 void re_decoder::_pulseEx(int gpio, int level, uint32_t tick, void *user)
 {
  re_decoder *mySelf = (re_decoder *) user;
  mySelf->_pulse(gpio, level, tick); 
 }

re_decoder::re_decoder(int gpioA, int gpioB, re_decoderCB_t callback)
{
  mygpioA = gpioA;
  mygpioB = gpioB;

  mycallback = callback;

  levA=0;
  levB=0;

  lastGpio = -1;

  gpioSetMode(gpioA, PI_INPUT);
  gpioSetMode(gpioB, PI_INPUT);

  gpioSetPullUpDown(gpioA, PI_PUD_UP);
  gpioSetPullUpDown(gpioB, PI_PUD_UP);

  gpioSetAlertFuncEx(gpioA, _pulseEx, this);
  gpioSetAlertFuncEx(gpioB, _pulseEx, this);
 }

void re_decoder::re_cancel(void)
{
 gpioSetAlertFuncEx(mygpioA, 0, this);
 gpioSetAlertFuncEx(mygpioB, 0, this);
 }

rotary_encoder.hpp

#ifndef ROTARY_ENCODER_HPP
#define ROTARY_ENCODER_HPP

#include <stdint.h>

typedef void (*re_decoderCB_t)(int);

class re_decoder
{
   int mygpioA, mygpioB, levA, levB, lastGpio;
   re_decoderCB_t mycallback;
   void _pulse(int gpio, int level, uint32_t tick);
   static void _pulseEx(int gpio, int level, uint32_t tick, void *user);

   public:
   void re_cancel(void);
};

#endif

test_encoder.cpp

#include <pigpio.h>
#include "rotary_encoder.hpp"

void callback(int way)
{
   static int pos = 0;
   pos += way;
   std::cout << "pos=" << pos << std::endl;
}

int main(int argc, char *argv[])
{
   if (gpioInitialise() < 0) return 1;
   re_decoder dec(7, 8, callback);
   sleep(3000);
   dec.re_cancel();
   gpioTerminate();
}

I have created qt widget project and added rotary_encoder.cpp hpp file but I have a problem with a test_encoder.cpp file. Can anyone suggest something?

Answer 1

you can add test_encoder.cpp in mainwindow.cpp and should create a pointer of class in mainwindow.h like this:

#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <rotary_encoder.h>
#include <QMainWindow>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private:
    Ui::MainWindow *ui;
    rotary_decoder *rc;
  void callback(int way);

};

and use main.cpp as default:

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}

mainwindow.cpp:

#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
     rc=new rotary_decoder();
     //your code
     //for call a function like:
     rc.re_cancel();
}

MainWindow::~MainWindow()
{
    delete ui;
}

void MainWindow::callback(int way)
{
    static int pos = 0;
       pos += way;
       qDebug() << "pos=" << pos ;
}