Add external signal on QAction
is there some possibility to add new signal to the QAction? With QPushButton you can do it easily but QAction does not know any signals except the pre defined signals.
Tell us more about what are you trying to achieve.
Anyway generic answers are: you can derive from QAction class and add the functionality you need, but first look at the "signals that are already there":http://doc.qt.digia.com/qt/qaction.html#signals - maybe what you need is already there.
Also you can connect signal to signal - so triggered signal can trigger one of your signals.
By clicking on open icon on the toolbar I want to call another class, which is done in the slot.
QAction* openAct = new QAction(QIcon(":/images/open.png"), tr("&Open..."), this);
openAct->setStatusTip(tr(" an existing file"));
connect(openAct, SIGNAL(setName(QString)), this, SLOT(callTheClass(QString)));
The problem is the signal: setName(QString) is not accepted by QAction
This doesn't make a lot of sense. The QAction indeed doesn't have a setName(QString) signal, but also it has no way to know what the name should be.
However, I guess what you could do, is create a QAction-derived class that shows a file open dialog that allows you to select a file, and then emit a signal with the selected file name. However, I think this is the wrong place to put this functionality.