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

问题

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 documentation for creating a menu to a very simple application. Unfortunately, it did not show up when the code was run. I am simply trying to add a “File” menu to the menu bar. I am running Mac OSX 10.9.3 and Qt Creator 5.3.1.

The screenshots of my code are below. I tried both the uncommented and commented code in the mainwindow.cpp source.

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    //myMenuBar = menuBar();
    //fileMenu = myMenuBar -> addMenu(tr("&File"));

    fileMenu = menuBar() -> addMenu(tr("&File"));

    ui->setupUi(this);
}

MainWindow::~MainWindow()
{
    delete ui;
}

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QMenuBar>
#include <QMenu>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit MainWindow(QWidget *parent = 0);
    ~MainWindow();

private:
    Ui::MainWindow *ui;
    QMenuBar* myMenuBar;
    QMenu* fileMenu;
};

#endif //MAINWINDOW_H

main.cpp

#include "mainwindow.h"
#include <QApplication>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}

ComeOnMenuBar.pro

#-------------------------------------------------
#
# Project created by QtCreator 2014-08-12T02:28:33
#
#-------------------------------------------------

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = ComeOnMenuBar
TEMPLATE = app


SOURCES += main.cpp\
        mainwindow.cpp

HEADERS  += mainwindow.h

FORMS    += mainwindow.ui

Any help would be really appreciated! Thank you!

Note: I know using setNativeMenuBar(false) works, but I would like the mac os native menu bar to work: the one that is displayed in the top-most left corner.

回答1:

I had same issued in ubuntu with python

I used menubar's setNativeMenubar method. You can find this in c++ pyqt docs.

    menu = self.menuBar()
    menu.setNativeMenuBar(False)

回答2:

It's pretty old Qt bug on OS X. You can work with QMenu and QMenuBar by calling QMenuBar::addAction, QMenuBar::removeAction and QMenuBar::insertAction. The trick is done by calling of QMenu::menuAction method.

Check the code below:

QMenu *menu = new QMenu("First menu");
menu->addAction("item 1");
menu->addAction("item 2");
m_menuBar->addAction(menu->menuAction());

Also you can check my another answer here with code snippet ready to compile and run.

回答3:

I know its late by 4 yrs, but i ran into same issue & spotted this on the Qt forum for ubuntu/Mac OS.

https://forum.qt.io/topic/7276/menu-not-showing-up-in-menubar/15

Add the following to your main.cpp before you declare your Mainwindow w:

QCoreApplication::setAttribute(Qt::AA_DontUseNativeMenuBar);

In my case my main.cpp file now looks like:

int main(int argc, char *argv[])
{
QApplication a(argc, argv);
AddressBook addressBook;
AddressBookController controller (&addressBook);
QCoreApplication::setAttribute(Qt::AA_DontUseNativeMenuBar); //fix for menubar notshowing in ubuntu

MainWindow w(&controller);
w.show();
return a.exec();

}