Trying to connect SecondWindow to MainWindow

[Eshya]

hi, right now i am trying to connect secondwindow exec from mainwindow

SecondWindow::SecondWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::SecondWindow)
{
    ui->setupUi(this);
    MainWindow _main;
    connect(this,&SecondWindow::closeTimer,_main,&MainWindow::closeTimer);


}

what is the correct way to to this concept

[JonB]

@Eshya said in Trying to connect SecondWindow to MainWindow:

exec

What does this mean? Are you by any chance thinking of QDialog::exec()??

MainWindow _main;

This cannot be right, it creates a brand new MainWindow. Not to mention that goes out of scope and gets destroyed at the closing }, so it won't be around for its slot to be called.

If you have some two separate instances of some MainWindow and some SecondWindow, you can connect signals/slots across them once they have been created somewhere which knows about them, like:

mainWindow = new MainWindow;
secondWindow = new SecondWindow;
connect(secondWindow, &SecondWindow::closeTimer, mainWindow, &MainWindow::closeTimer);

or appropriate this if you call this somewhere within either MainWindow or SecondWindow classes. In the usual case SecondWindow should not know about MainWindow, so probably not inside SecondWindow class. And connect()s should not be done at the signalling side, only at the slot object side, or somewhere which can see both the signalling & slot objects.

what is the correct way to to this concept

Don't know till I understand what "concept" you are trying to implement.

[Eshya]

@JonB no, i am doing this to call SecondWindow

main.h

SecondWindow *_secondwindow;

main.cpp

_secondwindow = new SecondWindow();
_secondwindow->show()
```

what I am trying to do is connect SecondWindow to emit function in MainWindow

[JonB]

@Eshya
So I gave you the code for exactly that in my answer.....

[jsulm]

@Eshya Isn't this same question as in https://forum.qt.io/topic/135973/how-to-connect-emitter-from-mainwindow-to-anotherwindow ?

[JonB]

@jsulm Very good observation...!