Add separate files for functions in qt creator - c++

Question

Hii I am new to programming i have stated learning about c++ and qt . i want to create a simple program in which user gives input from gui, these input are then send to a function (which is a separate header and cpp file) the value is evaluated in this function and again displayed in the gui.
i have three file namely main.cpp, (mainwindow.cpp & mainwindow.h), and (addition.cpp and addition.h)
i want that the values are read from mainwindow.ui (from lineedit) they are then send to the function addition.cpp and evaluated and is send back to mainwindow.cpp or mainwindow.ui (to lineedit) so that i can access this result.
here is the code i was trying
please help me in understanding the process
//main.cpp
#include "mainwindow.h"
#include <QApplication>
int main(int argc, char *argv[])
{
QApplication a(argc, argv);
MainWindow w;
w.show();
return a.exec();
}
//mainwindow.h.
#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include "addition.h"
#include <QMainWindow>
namespace Ui {
class MainWindow;
}
class MainWindow : public QMainWindow
{
Q_OBJECT
public:
explicit MainWindow(QWidget *parent = 0);
~MainWindow();
QObject *sumnum;
private:
Ui::MainWindow *ui;
float number1,number2;
public slots:
void results(float);
private slots:
void on_addnum_clicked();
};
#endif // MAINWINDOW_H
//mainwindow.cpp.
#include "mainwindow.h"
#include "ui_mainwindow.h"
MainWindow::MainWindow(QWidget *parent) :
QMainWindow(parent),
ui(new Ui::MainWindow)
{
ui->setupUi(this);
sumnum = new QObject(this);
connect(sumnum,SIGNAL(add(float)),this,SLOT(results(float)));
}
MainWindow::~MainWindow()
{
delete ui;
}
void MainWindow::results(float answer)
{
ui->sum->setText(QString::number(answer));
}
void MainWindow::on_addnum_clicked()
{
addresult(ui->num1->text().toDouble(),ui->num2->text().toDouble());
}
//addition.h
#ifndef ADDITION_H
#define ADDITION_H
#include <QObject>
class addition : public QObject
{
Q_OBJECT
public:
explicit addition(QObject *parent = 0);
void run(float, float);
private:
float answer;
signals:
void add(float);
public slots:
};
#endif // ADDITION_H
//addition.cpp
#ifndef ADDITION_H
#define ADDITION_H
#include <QObject>
class addition : public QObject
{
Q_OBJECT
public:
explicit addition(QObject *parent = 0);
void run(float, float);
private:
float answer;
signals:
void add(float);
public slots:
};
#endif // ADDITION_H

Answer 1

In your MainWindow class, the type of sumnum variable has to be addition because you'll need the complete type in order to connect to its signals/slots
sumnum class should have a public function like void add(flaot n1, float n2) so you can call it in your on_addnum_clicked function