How to perform action on clicking a QMenu object only?

Question

Here's a snapshot of the GUI. I want to perform simple actions solely by clicking on QMenu object Help. This QMenu object does NOT have any submenus.

Can you please advise me how to perform actions when only the QMenu is clicked Here's what I have tried, but I got an empty output.

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>
#include <QDebug>
#include <QSignalMapper>

namespace Ui {
class MainWindow;
}

class MainWindow : public QMainWindow
{
    Q_OBJECT

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

private:
    Ui::MainWindow *ui;
    void createActions();
    QSignalMapper *pSignalMapper;

private slots:
    void help();

};

#endif // MAINWINDOW_H

mainwindow.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
MainWindow::MainWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::MainWindow)
{
    ui->setupUi(this);
    createActions();
}

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

void MainWindow::createActions()
{
    pSignalMapper = new QSignalMapper(this);
    connect(ui->menuHelp, SIGNAL(triggered(QAction*)), this, SLOT(help()));

}

void MainWindow::help()
{
    qDebug()<<"inside help qdialog";
}

main.cpp

#include "mainwindow.h"
#include <QApplication>
#include <ui_mainwindow.h>
int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    MainWindow w;
    w.show();

    return a.exec();
}

Output when I click on Help QMenu, absolutely nothing:

Starting E:\Qt2\modules\guiPrototype2\build-guiPrototype2-Desktop_Qt_5_2_0_MSVC2010_32bit-Debug\debug\guiPrototype2.exe...

Answer 1

I would try to do the following:

void MainWindow::createActions()
{
    [..]
    connect(ui->menuHelp, SIGNAL(aboutToShow()), this, SLOT(help()));
}

void MainWindow::help()
{
    qDebug()<<"inside help qdialog";
}