QT Signals and Slots, dynamic menubar

Question

I am new to qt and I want to know how to make a dynamic menu. I did get it to make new submenus but I don't know how I can implement the "triggered() function" of these dynamic made submenus, so that I have access to what happens if I want to click on such a new submenu.

Here what I have so far (with: vector<QString> = vec; and some .ui Window named "New_Window") in mainwindow.cpp in some function:

QMenu *menu = this->menuBar()->addMenu("Chat Members");
    for (int i = 0; i < vec.size(); ++i){
            QString name = vec.at(i);
             QAction *act = menu->addAction(name);
             New_Window* new_window = new New_Window;
             QObject::connect(act,SIGNAL(triggered()),
                             new_window,SLOT(actionReaction()));
        }

Can you clarify exactly what you mean by 'dynamic menu'? You can be notified just before a menu is shown by connecting to the [`QMenu::aboutToShow`](https://doc.qt.io/qt-5/qmenu.html#aboutToShow) signal. — G.M., Oct 29 '21 at 18:18
By dynamic menu I mean a menu that is created during execution of the app. — cretos, Oct 29 '21 at 19:49
By dynamic menu I mean submenus that arent there at the beginning but are created during execution of the app. I can see the menubars that are being created, that isnt the problem, but I don't know how I can add a function to the button for example how to open a new window with this newly created menubuttons. — cretos, Oct 29 '21 at 19:55

score 1 · Accepted Answer · answered Oct 29 '21 at 22:47

here is an example of how a signal slot with a dynamic interface works , class A is created after starting the program, then the user clicks on a button from class A, for example, a class A is created many times and we need to determine from what object we get a signal to press the button, so

    class A : public QMainWindow
    {
        Q_OBJECT
    public:  
        A(QWidget *parent = nullptr);
        ~A(); 
        void setID(const int id);  
        void getId() const; 
    signals:
        void onButtonPress(int ID); 
    private:
        int mID;
    };

here we create a new class A and store it in the vector in such a way,

QVector<A*> mCreatingClassA;

void createNewClassA 
{
    QVector<A*> mCreatingClassA;
    ....
    A* a = new A();
    int id = // create your unique ID
    a->setId(id);
    connect(a,SIGNAL(onButtonPress(int)),this,SLOT(onyourSlot(int)));
    mCreatingClassA.push_back(a);
    ....
    
}

detect the object from which the signal was received)

void onyourSlot(int ID)
{
    for (int i = 0; i < mCreatingClassA.size(); ++i) {
        if(mCreatingClassA[i]->getId()==ID)
        {
            mCreatingClassA[i] // received a signal from this object
        }
    }
}

QT Signals and Slots, dynamic menubar

1 Answers1