问题
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...
回答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";
}
回答2:
The reason it doesn't work, is because you are not triggering any action.
This signal is emitted when an action in a menu belonging to this menubar is triggered as a result of a mouse click; action is the action that caused the signal to be emitted.
What you should do is add an action to your QMenuBar
instead of a QMenu
.
QAction *helpAction = ui->menuBar->addAction("Help");
connect(helpAction, SIGNAL(triggered()), this, SLOT(help()));
来源:https://stackoverflow.com/questions/22197496/how-to-perform-action-on-clicking-a-qmenu-object-only