Crash on menuBar() after setMenuWidget()

[Paddle]

I'm adding an option for frameless window to an application.
For this I wanted to use setMenuWidget. So in my mainWindow Ctor I'm doing :

auto* titleBar = new CustomTitleBar(this);
    setMenuWidget(titleBar);

Now the thing is that this is an option. So somewhere down the line I have :

void MenuManager::setup(MenuItem* menuItems) const
{
    QMenuBar* menuBar = getMainWindow()->menuBar();
    QMenu* mainMenu = nullptr;
    if (!menuBar) {
        auto* ctb = dynamic_cast<CustomTitleBar*>(getMainWindow()->menuWidget());
        if (ctb) {
            mainMenu = ctb->mainMenu();
        }
    // Then populate either the menubar or the mainMenu...
    }

And the issue is that doing menuBar() crashes the application. I would have expected menuBar() to return nullptr after setMenuWidget has been used. What am I doing wrong?

[Pl45m4]

@Paddle said in Crash on menuBar() after setMenuWidget():

I would have expected menuBar() to return nullptr after setMenuWidget has been used.

What made you think that?

• https://doc.qt.io/qt-6/qmainwindow.html#menuBar
• https://doc.qt.io/qt-6/qmainwindow.html#menuWidget

[Paddle]

Thanks for the reply.
Ok so menuBar creates a menubar when there is none.

Please note that it still crashes. Which is bad.

Why would I think that? Because this function looks like a getter. For instance menuWidget() does exactly what I expected menuBar would do. IMO it's bad that menuBar creates a menu.

[Christian Ehrlicher]

@Paddle said in Crash on menuBar() after setMenuWidget():

QMenuBar* menuBar = getMainWindow()->menuBar();

Use a debugger and see where it crashes. Since getMainWindow() is your own function I would guess it returns a nullptr.