QObject::connect: No such slot

[d_stranz]

For future users I can give one advice - don't connect no arguments signals with no argument slots. It was my main problem in this example.

This is not good advice at all. It is always appropriate to connect a signal with no arguments to a slot with no arguments. In fact, it is the only way such a signal can be connected. QPushButton::clicked() and QAction::triggered() are two very, very common cases of such signals*, and connecting them to no-argument slots is the only way to handle those signals.

I think you still have a basic misunderstanding of signals and slots, otherwise you would not make such a statement.

*Edit: QAbstractButton::clicked() and QAction::triggered() are actually overloaded methods - they come in two forms, one with a bool "checked" argument and another with the bool argument defaulted to false. The signals are usually connected to no-argument slots, which means the bool argument is ignored.