QtDesignPatterns/observerpattern/subject.h

#include <vector>
#include "interface.h"

class Subject
{
public:
    Subject(size_t state) : state(state) {}
    size_t getState()
    {
        return this->state;
    }
    void setState(size_t state)
    {
        this->state = state;
        notifyAllObservers();
    }
    void attach(Observer *observer)
    {
        vector.push_back(observer);
    }
    void notifyAllObservers()
    {
        for(auto itor : vector)
        {
            itor->update();
        }
    }

private:
    std::vector<Observer*> vector;
    size_t state;
};