C++ 0x11 - std::bind 和组合

Question

我想在使用组合时将成员类事件绑定(bind)到消费者类函数。如果问题描述有误请指正，我是C#出身。

代码如下:

#include "stdafx.h"
#include <functional>
#include <iostream>

using namespace std::placeholders;

class Observable
{
public:
    void Register(std::function<void()> Callback)
    {

    }
    std::function<void()> OnStateChanged;

    void ChangeState()
    {
        std::cout << "DevicioClient::ChangeState" << std::endl;
        OnStateChanged();
    }
};

class Observer
{
    Observable client;

    void OnStateChanged()
    {
        std::cout << "DevicioConsumer::OnStateChanged" << std::endl;
    }
public:
    void Run()
    {
    // does work
        client.OnStateChanged = []{
            std::cout << "client.OnStateChanged" << std::endl;
        };
    // doesn't work
    //  OnStateChanged = std::bind(&Observable::OnStateChanged, this);

        client.ChangeState();
    }
};
int _tmain(int argc, _TCHAR* argv[])
{
    Observer consumer;
    consumer.Run();

    getchar();
    return 0;
}

我想在 Observable 调用 OnStateChanged 函数时运行 Observer::OnStateChanged。

Answer 1

它说 &Observable::OnStateChanged 是你试图绑定(bind)的函数……你是说 &Observer::OnStateChanged 吗？因为这工作正常:

client.OnStateChanged = std::bind(&Observer::OnStateChanged, this);