Qt 5 C++ undefined reference to Class::function(QString, Qstring, ...) - c++

Question

i know this question has been answered in this forum before, but I need more specific help.
Here's the code:
sessionwindow.cpp
#include "sessionwindow.h"
#include "ui_sessionwindow.h"
#include "session.h"
#include "utils.h"
#include <QStringList>
SessionWindow::SessionWindow(QWidget *parent) : QDialog(parent), ui(new Ui::SessionWindow)
{
ui->setupUi(this);
this->setFixedSize(this->size());
}
SessionWindow::~SessionWindow()
{
delete ui;
}
void SessionWindow::on_cancelBtn_clicked()
{
close();
}
void SessionWindow::on_createBtn_clicked()
{
QString min = (ui->isMin) ? "min" : "nomin";
QString sp = (ui->spHidd) ? "nosp" : "sp";
QString name = ui->sessionName->text();
QString user = ui->skUser->text();
QString pass = ui->skPass->text();
Utils u;
u.createSession(name, user, pass, min, sp);
}
utils.h (Where the function prototype is declared)
#ifndef UTILS_H
#define UTILS_H
#include <QString>
#include <QStringList>
class Utils
{
public:
Utils();
~Utils();
void startSkype(QString, QString, QStringList);
void createSession(QString , QString, QString, QString, QString);
};
#endif // UTILS_H
utils.cpp (Where the function is)
#include "utils.h"
#include "session.h"
#include <QString>
#include <QStringList>
#include <QVector>
#include <QDebug>
QVector<Session> sessions;
Utils::Utils()
{
}
Utils::~Utils()
{
}
void Utils::startSkype(QString user, QString pass, QStringList options)
{
}
void createSession(QString name, QString user, QString pass, QString isMin, QString spHid)
{
sessions.append(Session(name, user, pass, isMin, spHid));
}
The problem is tha I can't compile it, it just throws an error: undefined reference to `Utils::createSession(QString, QString, QString, QString, QString)'
Sorry if I explained bad and thanks for the help!! :D

Answer 1

You forgot to put Utils:: in front of your method definition:
void createSession(QString name, QString user, QString pass, QString isMin, QString spHid)
{
sessions.append(Session(name, user, pass, isMin, spHid));
}
should be
void Utils::createSession(QString name, QString user, QString pass, QString isMin, QString spHid)
{
sessions.append(Session(name, user, pass, isMin, spHid));
}