cannot change main window title

a very basic and simple question which is puzzling me

i want to change the title of the main window in my qt application (the GUI has been designed by Qt Design so I have the ui. and setupui() stuff)

Code:

---

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent)
{
    QString windowTitle("some good stuf here");
    QMessageBox::information(this, progName, windowTitle );
 
//....
    this->setWindowTitle(windowTitle); // ???
 
    ledGreen.load(":/bitmap/LED-Green-20.bmp");
    ledRed.load(":/bitmap/LED-Red-20.bmp");
    ledDark.load(":/bitmap/LED-Dark-20.bmp");
    ui.setupUi(this);
 
//....
}

---

can't understand what is wrong here ...

thanks much

Code:

---

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent)
{
    QString windowTitle("some good stuf here");
    QMessageBox::information(this, progName, windowTitle );
 
//....
    //this->setWindowTitle(windowTitle); // ??? //<<<<<<<<<<<<<<<<<<<<<< Move it, after setupUi();
 
    ledGreen.load(":/bitmap/LED-Green-20.bmp");
    ledRed.load(":/bitmap/LED-Red-20.bmp");
    ledDark.load(":/bitmap/LED-Dark-20.bmp");
    ui.setupUi(this);
 
    this->setWindowTitle(windowTitle); //<<<<<<<<<<<<<<<<<<<<<<Here
 
//....
}

---