问题
#include <QtCore/QCoreApplication>
#include <boost/bind.hpp>
#include <boost/function.hpp>
class button
{
public:
boost::function<void()> onClick;
boost::function<void(int ,double )> onClick2;
};
class player
{
public:
void play(int i,double o){}
void stop(){}
};
button playButton, stopButton;
player thePlayer;
void connect()
{
//error C2298: 'return' : illegal operation on pointer to member function expression
playButton.onClick2 = boost::bind(&player::play, &thePlayer);
stopButton.onClick = boost::bind(&player::stop, &thePlayer);
}
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
connect();
return a.exec();
}
回答1:
boost::bind(&player::play, &thePlayer)
You need to use placeholders for the two arguments:
boost::bind(&player::play, &thePlayer, _1, _2)
The placeholders allow you to say "I'm only binding certain arguments; other arguments will be provided later."
回答2:
And if you want create portable code - specify namespace of placeholders directly:
boost::bind( &player::play, &thePlayer, ::_1, ::_2 ); // Placeholders of boost::bind are placed in global namespace.
来源:https://stackoverflow.com/questions/4929537/how-can-i-use-boostbind-to-bind-a-class-member-function