How to reach any class members from Mainwindow class?

[ELIF]

I have a QT Widget application. I
I want to reach ismet class members from mainwindow.cpp file
In mainwindow.cpp

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

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{

     is=new ismet();
     is->My_Func(2);

}

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

In mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H


#include <QMainWindow>
#include "ismet.h"


namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

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


private:
    Ui::MainWindow *ui;
};

#endif // MAINWINDOW_H

In ismet.cpp

ismet::ismet()
{
    My_Func(2);
}


void ismet::My_Func(int x){
    qDebug()<<x;

}

In ismet.h

#ifndef ISMET_H
#define ISMET_H

#include<QDebug>
#include<QObject>
#include<QString>
#include<QMainWindow>

class ismet : public QObject
{
public:
    ismet();

    void My_Func(int x);//declaration
    QString myname;
};

#endif // ISMET_H

My error is : error: undefined reference to ismet::ismet()' undefined reference to ismet::My_Func(int)'

How to solve this issue?

[kkoehne]

Please post your build system configuration (CMakeLists.txt file , or .pro file). Are you actually compiling and linking ismet.cpp into the executable?

[ELIF]

#-------------------------------------------------
#
# Project created by QtCreator 2022-06-27T14:19:26
#
#-------------------------------------------------

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = calisma
TEMPLATE = app

# The following define makes your compiler emit warnings if you use
# any feature of Qt which has been marked as deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0


SOURCES += \
        main.cpp \
        mainwindow.cpp \
    ismet.cpp

HEADERS += \
        mainwindow.h \
    ismet.h

FORMS += \
        mainwindow.ui

[kkoehne]

This looks correct to me. Can you also post the full compiler output (not just the error message, but everything in Qt Creator under 'Compile Output')?

[jsulm]

@ELIF You can also try complete rebuild:

1. Delete build folder
2. Run qmake
3. Build

Maybe qmake was not executed after addin ismet.cpp to pro file.