This was missing for a while, and there is nothing fundamentally missing for it to work. With the more recent work around slot objects and invokeMethod in general, it is a good time to add support for this. In this patch, when connecting to a functor, it automatically deduces the overload to call based on the arguments passed to invokeMethod. Sharing code with QObject::connect could be done, but they have a key difference that makes it harder: With signal emissions we throw away trailing arguments that are not used: i.e. `signal(int, int)` can be connected to `slot(int)` or `slot()`. With invokeMethod that's not a thing. So we will need a way to toggle that behavior during resolution. [ChangeLog][QtCore][QMetaObject] Added support for passing parameters to the overload of QMetaObject::invokeMethod that takes a functor. These new overloads must have the return-value passed through qReturnArg(). Change-Id: If4fcbb75515b19e72fab80115c109efa37e6626e Reviewed-by: Ievgenii Meshcheriakov <ievgenii.meshcheriakov@qt.io> Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>