Boost Signals2跟蹤

Question

我在我們的項目之一中使用了Boost Signals2。在這個我想要自動連接管理，爲此我正在測試Boost Signals2跟蹤，但我沒有獲得槽位調用。 運行以下代碼後，不會調用插槽。 環境： VS 2010，Windows 7中，提高1.54

#include <stdio.h> 
    #include <iostream> 
    #include <string> 
    #include <boost/bind.hpp> 
    #include <boost/enable_shared_from_this.hpp> 
    #include <boost/signals2/signal.hpp> 
    #include <boost/shared_ptr.hpp> 


    typedef boost::signals2::signal<void()> signal_test; 
    using namespace boost; 

    class SubjectTest 
    { 

    public: 
     void Connect(const signal_test::slot_type &subscriber) 
     { 
      m_Signal.connect(subscriber); 
      std::cout << "No of connections : " << m_Signal.num_slots() << std::endl; 
     } 
     void Notify() 
     { 
      m_Signal(); 
     } 
    private: 
     signal_test m_Signal; 
    }; 

    class Listner 
    { 
    public: 
     Listner(){} 
     ~Listner(){} 
     Listner(std::string name) 
     :m_name(name) 
     { 
     } 
     void GotSignal() 
     { 
      std::cout << m_name << std::endl; 
     } 
     void ConnectWithTracking(SubjectTest *s) 
     { 
      shared_ptr<Listner> l = new Listner(); 
      s->Connect(signal_test::slot_type(&Listner::GotSignal,l.get()).track(l)); 

     } 
     void ConnectNormal(SubjectTest *s) 
     { 
      s->Connect(bind(&Listner::GotSignal,this)); 

     } 

    private: 
     std::string m_name; 
     shared_ptr<Listner> l; 
    }; 

    void main() 
    { 
     Listner l2("First"); 
     SubjectTest sub; 

     try 
     { 
     l2.ConnectWithTracking(&sub); 
     //l2.ConnectNormal(&sub); 
     sub.Notify(); 

     { 
      Listner l3("Second"); 

      l3.ConnectWithTracking(&sub); 
      //l3.ConnectNormal(&sub); 
      sub.Notify(); 
     } 

     sub.Notify(); 
     } 
     catch(std::exception ex) 
     { 
      std::cout << ex.what() << std::endl; 
     } 

     std::cout << "Finish" <<std::endl; 
    } 

更新時間： * 工作現在 *

#include <stdio.h> 
    #include <iostream> 
    #include <string> 
    #include <boost/bind.hpp> 
    #include <boost/enable_shared_from_this.hpp> 
    #include <boost/signals2/signal.hpp> 
    #include <boost/shared_ptr.hpp> 


    typedef boost::signals2::signal<void()> signal_test; 
    using namespace boost; 

    class SubjectTest 
    { 

    public: 
     void Connect(const signal_test::slot_type &subscriber) 
     { 
      m_Signal.connect(subscriber); 
      std::cout << "No of connections : " << m_Signal.num_slots() << std::endl; 
     } 
     void Notify() 
     { 
      m_Signal(); 
     } 
    private: 
     signal_test m_Signal; 
    }; 

    class Listner : public boost::enable_shared_from_this<Listner> 
    { 
    public: 
     Listner(){} 
     ~Listner(){} 
     Listner(std::string name) 
     :m_name(name) 
     { 
     } 
     void GotSignal() 
     { 
      std::cout << m_name << std::endl; 
     } 
     void ConnectWithTracking(SubjectTest *s) 
     { 
      s->Connect(signal_test::slot_type(&Listner::GotSignal,shared_from_this().get()).track(shared_from_this())); 
     } 
     void ConnectNormal(SubjectTest *s) 
     { 
      s->Connect(bind(&Listner::GotSignal,this)); 
     } 

    private: 
     std::string m_name; 

    }; 

    void main() 
    { 
     shared_ptr<Listner> l2(new Listner("First")); 

     SubjectTest sub; 

     try 
     { 
     l2->ConnectWithTracking(&sub); 

     sub.Notify(); 

     { 
      shared_ptr<Listner> l3(new Listner("Second")); 

      l3->ConnectWithTracking(&sub); 
      //l3.ConnectNormal(&sub); 
      sub.Notify(); 
     } 

     sub.Notify(); 
     } 
     catch(std::exception ex) 
     { 
      std::cout << ex.what() << std::endl; 
     } 

     std::cout << "Finish" <<std::endl; 
    } 

現在，這是SIGNAL2自動連接管理的完整的例子

Answer 1

{ 
    shared_ptr<Listner> l(new Listner()); 
    s->Connect(signal_test::slot_type(&Listner::GotSignal,l.get()).track(l)); 
} 

In t他在線l pointee在關閉}被摧毀 - 意味着您剛剛連接的插槽已過期。

跟蹤的要點是傳遞給track() a shared_ptr（或weak_ptr），它與插槽本身綁定（或緊密相關）。通過一個shared_ptr沒有意義，它的壽命與插槽本身的壽命無關。