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How read a file and print values in Qt5 ?



  • Hi all,

    I did a C++ program wich read a text file, transform it in "int" and print values.
    My question is how to do the same with Qt using Signal and Slots ?
    I don't have any idea of how to do it.

    This is my C++ code:

    @
    #include <string>
    #include <fstream>
    #include <iostream>
    #include <stdlib.h>
    #include <unistd.h>

    #define TEMP_PHYSIC "/sys/class/hwmon/hwmon1/device/temp1_input"
    #define TEMP_CORE_1 "/sys/class/hwmon/hwmon1/device/temp2_input"
    #define TEMP_CORE_2 "/sys/class/hwmon/hwmon1/device/temp3_input"
    #define TEMP_CORE_3 "/sys/class/hwmon/hwmon1/device/temp4_input"
    #define TEMP_CORE_4 "/sys/class/hwmon/hwmon1/device/temp5_input"

    using namespace std;

    class Temp
    {
    public:

        string tempPhys();
        string tempCore1();
        string tempCore2();
        string tempCore3();
        string tempCore4();
    

    };

    string Temp::tempPhys()
    {
    ifstream fichierPhys(TEMP_PHYSIC);
    if(fichierPhys)
    {
    string lignePhys;
    while(getline(fichierPhys, lignePhys))
    {
    return lignePhys;
    }
    }
    }

    string Temp::tempCore1()
    {
    ifstream fichierCore1(TEMP_CORE_1);
    if(fichierCore1)
    {
    string ligneCore1;
    while(getline(fichierCore1, ligneCore1))
    {
    return ligneCore1;
    }
    }
    }

    string Temp::tempCore2()
    {
    ifstream fichierCore2(TEMP_CORE_2);
    if(fichierCore2)
    {
    string ligneCore2;
    while(getline(fichierCore2, ligneCore2))
    {
    return ligneCore2;
    }
    }
    }

    string Temp::tempCore3()
    {
    ifstream fichierCore3(TEMP_CORE_3);
    if(fichierCore3)
    {
    string ligneCore3;
    while(getline(fichierCore3, ligneCore3))
    {
    return ligneCore3;
    }
    }
    }

    string Temp::tempCore4()
    {
    ifstream fichierCore4(TEMP_CORE_4);
    if(fichierCore4)
    {
    string ligneCore4;
    while(getline(fichierCore4, ligneCore4))
    {
    return ligneCore4;
    }
    }
    }

    int main()
    {
    while(true)
    {
    Temp temp;
    int c0, c1, c2, c3, c4;

        c0 = atoi(temp.tempPhys().c_str());
        c1 = atoi(temp.tempCore1().c_str());
        c2 = atoi(temp.tempCore2().c_str());
        c3 = atoi(temp.tempCore3().c_str());
        c4 = atoi(temp.tempCore4().c_str());
    
        cout << "Temp. Physic : " << c0/1000 << " °c" << endl;
        cout << "====================" << endl;
        cout << "Temp. Core 1 : " << c1/1000 << " °c" << endl;
        cout << "Temp. Core 2 : " << c2/1000 << " °c" << endl;
        cout << "Temp. Core 3 : " << c3/1000 << " °c" << endl;
        cout << "Temp. Core 4 : " << c4/1000 << " °c" << endl;
        cout << "====================" << endl;
    
        usleep(100000);
        system&#40;"clear"&#41;;
    }
    return 0;
    

    }
    @

    Thanks a lot for your help.

    Regards,

    Chris.


  • Lifetime Qt Champion

    Hi,

    QObject for the base class
    QFile for the file reading part
    QTimer to trigger it at regular interval

    If you are using C++11 you can even use directly a lambda

    On the other hand you could also try QSocketNotifier so you should get notifications when there's new data to read

    Hope it helps


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