c++ - boost signal-slot generalisation -


i searching way implement this, using boost

class genboost{   boost::signal<void(void)> m_signal;   std::function<void (bool)> m_function    public:     void setsignal(boost::signal<void(void)> sigarg)     {        m_signal = sigarg;     }      void setfunction(std::function<void (bool)> &functionarg)     {        m_function = functionarg;        m_signal.connect(boost::bind(&gebboost::onsignal,this,_1));      }      void onsignal(){         //do     }  };

how can achieved. signal copying not possible!?

i not 100% sure of intent, assuming onsignal() not need interact m_signal (and need 1 connection m_signal), appears can decouple m_signal class entirely. example, if not want body of 'onsignal()' called until 'm_function' has been set, like:

class genboost{     std::function<void (bool)> m_function;     boost::signals::scoped_conection m_connection;    public:     void setsignal(boost::signal<void(void)>& sigarg)     {         m_connection = sigarg.connect(boost::bind(&gebboost::onsignal,this));     }      void setfunction(std::function<void (bool)> &functionarg)     {         m_function = functionarg;     }      void onsignal()     {         if ( m_function )             do_work();     }      void do_work()     {         //do     } };

note stripped last _1 m_signal.connect(boost::bind(&gebboost::onsignal,this,_1)); because signal declared type void(void) should connected void callback. added scoped_connection if object of type genboost destroyed before signal connected to, automatically disconnect rather allow signal retain invalid pointer.

alternatively, if needed retain reference original signal, add original signal member, pointer boost::signal<void(void)>* m_signal;. setsignal becomes:

void setsignal(boost::signal<void(void)>& sigarg) {     m_signal = &sigarg;     m_connection = m_signal->connect(boost::bind(&gebboost::onsignal,this)); }

i still recommend using scoped connection , connecting in setsignal ensure have 1 connection 1 signal (if setsignal called twice, connection first signal automatically disconnected). if go pointer route, must externally ensure passed-in signal has lifetime longer genboost object.


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