MenuBar Not Showing for Simple QMainWindow Code, Qt Creator Mac OS

Question

I have been having problems adding a menu item to the built in menu bar in a Qt desktop application. I copied the code provided in the QMainWindow class reference documentat

Answer 1

In order for OS X to gain control over the menu bar, you need to create the menu bar without a parent widget. This means in the mainwindow.cpp file typically, you'd have to create your menu bar in code.

This is my code that also puts in the About and Preferences menu items in the PROGRAM menu drop down as is standard on a mac:

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    this->aboutAction = new QAction(0);
    this->aboutAction->setMenuRole(QAction::AboutRole);
    this->aboutWindow = new About();
    this->preferencesAction = new QAction(0);
    this->preferencesAction->setMenuRole(QAction::PreferencesRole);
    this->preferencesWindow = new Preferences();
    this->mainMenuBar = new QMenuBar(0);  // 0 explicitly states to create it with no parent
    this->mainMenu = new QMenu(0);        // Same here
    this->mainMenuBar->addMenu(this->mainMenu);
    this->mainMenu->addAction(this->aboutAction);
    this->mainMenu->addAction(this->preferencesAction);
    this->setMenuBar(this->mainMenuBar);
    // ...
}

Preferences and About are classes that handle their respective windows and code isn't included.

You will need to remove the menu bar in the mainwindow ui form that gets automatically generated.