SIGNALSLOT or Q_INVOKABLE to access C++

Perhaps you mean QGraphicsItem::mouseDoubleClickEvent() Having that function emit a signal is trivial if your item also inherits from QObject

A signal in Qt is declared much like a member function, except that it has no local implementation

cash crazy slot A slot is called when a signal connected to it is emitted Slots are normal C++ functions and can be called normally; their only special feature is that signals

coin slot body modification Perhaps you mean QGraphicsItem::mouseDoubleClickEvent() Having that function emit a signal is trivial if your item also inherits from QObject