When you call:
QWidgetAction::setEnabled( bool b )
It is expect for all widgets in
QWidgetAction::createdWidgets()
to take the same enabled state, the same for all subclasses of QWidgetAction.

Currently this is not the case.

It just works for subclasses which are aware of the action and react to its
changes itself, like QToolButton does (via the QActionEvent emitted by
QAction::setEnabled() and QToolButton::actionEvent()). This should be
mentioned in the documentation of QWidgetAction.

It may be useful to change QWidgetAction to just do that and
sync all created widgets to its enabled state as where would this be unwanted?