boost-signals

问题 Boost.Signals allows various strategies of using the return values of slots to form the return value of the signal. E.g. adding them, forming a vector out of them, or returning the last one. The common wisdom (expressed in the Qt documentation [EDIT: as well as some answers to this question ] ) is that no such thing is possible with Qt signals. However, when I run the moc on the following class definition: class Object : public QObject { Q_OBJECT public: explicit Object( QObject * parent=0 )

问题 I am getting such a crash: #0 0x90b05955 in __gnu_debug::_Safe_iterator_base::_M_detach #1 0x90b059ce in __gnu_debug::_Safe_iterator_base::_M_attach #2 0x90b05afa in __gnu_debug::_Safe_sequence_base::_M_detach_all #3 0x000bc54f in __gnu_debug::_Safe_sequence_base::~_Safe_sequence_base at safe_base.h:170 #4 0x000aac05 in __gnu_debug::_Safe_sequence<__gnu_debug_def::vector<boost::signals::trackable const*, std::allocator<boost::signals::trackable const*> > >::~_Safe_sequence at safe_sequence.h

问题 Consider this: #include <boost/signals2.hpp> #include <iostream> struct object_with_slot { void operator()() { std::cout << "Slot called!" << std::endl; member = 50500; } int member; }; int main() { boost::signals2::signal<void ()> sig; object_with_slot * ptr = new object_with_slot; sig.connect(*ptr); delete ptr; sig(); } Output is "Slot called!" and no crash or anything. That's why I have a few questions: 1) Why there is no crash? 2) Why there is no crash even if the slot function assigns

问题 I have a TcpDevice class which encapsulates a TCP connection, which has an onRemoteDisconnect method which gets called whenever the remote end hangs up. Then, there's a SessionManager object which creates TcpSession objects which take a TcpDevice as a communication channel and inserts them in an internal pointer container for the application to use. In case any of the managed TcpSessions should end, I would like the SessionManager instance to be notified about it and then remove the

问题 I've recently switched from visual studio 2010 express to using NetBeans, and i'm already very impressed with the layout and simplicity, even though it did take a bit of nudging to compile right. However, i've got another problem. When i tested to see if boost would work as well, i included the file boost/signals.hpp in a main.cpp and then went to the additional library directories in the project options and added the lib directory of my boost install, same as i would do in visual studio.

问题 When using Boost.Signals, boost allows you to derive from boost::signals::trackable in order to ease object/connection lifetime management (See the boost documentation). I am in an early stage of my project and I am thinking, whether to derive from boost::signals::trackable in every new class I write that might use Boost.Signals in the future or only in classes I am sure that they will need the functionality of the trackable bas e-class The main reason for th first approach would be to

问题 I'm building with g++, and yesterday a helpful person on SO told me to compile with the -D_GLIBCXX_DEBUG and -D_GLIBCXX_DEBUG_PEDANTIC flags. I did so, and I spent most of yesterday tweaking my code to conform to these flags. Now it's complaining about my use of boost::signal , and I'm not sure where the problem is. I have a class Yarl that has a function refresh() that I want to bind to a signal sigRefresh in another class EventHandler : class Yarl { private: void refresh(); (...) }; class

问题 I was wondering if there is a nicer way to connect a Boost signal of one class directly to a signal of another class? For example imagine a facade class with a bunch of members which provide their own signals. Now assume that the facade wants to expose these signals. I usually end up writing boilerplate methods which I then connect as signal handlers. using namespace boost::signal; class A { public: A(){}; virtual ~A(){}; signal<void()> signalA; }; class B { public: B(){}; virtual ~B(){};

问题 My system is having trouble building the boost libraries. I understand that most boost libraries are (fortunately) just headers that do not need to be build (with some exceptions). Does the boost :: signals2 library need to be built? Also is the boost.signals2 library dependant on the boost.signals library? 回答1: Signals is not header-only, signals2 is. But however, signals2 is explicitly developed for thread-safety and if you use boost.thread, this has to be compiled. As far as I know

问题 Recently I had a class that looked like class IGraphElement{ typedef void FuncCharPtr(char*, int) ; public: void Add(FuncCharPtr* f) { FuncVec.push_back(f); } void CastData(char * data, int length){ for(size_t i = 0 ; i < FuncVec.size(); i++){ char* dataCopy = new char[length]; memcpy(dataCopy, data, length); FuncVec[i](dataCopy, length); } } private: vector<FuncCharPtr*> FuncVec ; }; There I was giving to all subscribers a pointer to there copy of data. Now I want to make my class to use