c++ - Cannot connect signal from base class -

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when try connect base class signal, qt tells me signal not exists on derived class.

why that? how can tell connect use base class?

namespace mynamespace  {  void register(derived* derived) {     // error msg     // qobject::connect: no such signal mynamespace::derived::basesignal()      qobject::connect( derived, signal(basesignal()),                        foo,     slot(fooslot()));  }  class base : public qobject {     q_object  signals:     void basesignal(); };  class derived : public qobject,                 public base {     q_object  signals:     void derivedsignal(); };  } // namespace mynamespace

it better in form:

namespace mynamespace  {  class base : public qobject {     q_object  signals:     void basesignal(); };  class derived : public base {     q_object  signals:     void derivedsignal(); };  void registerx( derived* derived ) {     qobject::connect( derived, signal(basesignal()), foo, slot(fooslot())); }  } // namespace mynamespace

as this post says shall not inherit qobject multiple times.


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