STL for_each and iterator implemmentation?

Hi!

This is my first time that I am using STL and I have some question about it.
The thing that I am trying to do is to use for_each algorithm on a array of  structurs. So i have created a class that is handling this array and a iterator class to use for the for_each algorithm.

First my MessageHandler this is the class handling the structur
typedef struct{
        unsigned __int32 Param_code;
        unsigned __int32 Time;
        unsigned __int32 Measure_Value;
}S_record;
typedef struct{
        //--------HEADERS-------
        unsigned __int16 STX;
      unsigned __int16 CRC;
        unsigned __int16 MachID;
        unsigned __int16 ClinicalSWID;
        unsigned __int32 MsgCounter;
        unsigned __int32 CmdCode;
        unsigned __int32 MsgInfo;
        unsigned __int32 Flags;
        unsigned __int32 PatId;
        //----------------------
        S_record records[8];
}Message;

class MessageIterator;

class MessageHandler {
        friend class MessageIterator;
        public:
                MessageHandler(Message* mes);
                .....
                ..........
                MessageIterator begin();
                MessageIterator end();
        private:
                .....
                Message* message;
};
MessageIterator MessageHandler::begin() {
        return  MessageIterator(*this, 0);
}
MessageIterator MessageHandler::end() {
        int size = sizeof(message->records) / sizeof(S_record);
        return  MessageIterator(*this, size);
}

and then i have the iterator class
class MessageIterator {
        public:
                MessageIterator(MessageHandler& m, int p) : mh(m), pos(p) {};
                bool operator!=(const MessageIterator& messitr) const;
                MessageIterator& operator++();
                S_record operator*();
        private:
                MessageHandler mh;
                int pos;
};
bool MessageIterator::operator!=(const MessageIterator& messitr) const {
        return (pos != messitr.pos);
}
MessageIterator& MessageIterator::operator++() {
        ++pos;
        return *this;
}
S_record MessageIterator::operator*() {
        return mh.message->records[pos];
}

and then in a button even I would like to use for_each like this

std::for_each(mh.begin(), mh.end(), function to plot values);

the problem is that i dont know for sure how to use the for each. the function should plot two values from each record in the arry on a graph, something like graph1->plot_XY(each_record.x,each_record.y);

The closest i have com is following

template<class T> struct print : public std::unary_function<T, void>
{
  print(TGraph& g) : graph(g) {}
  void operator() (T x) { graph.plot_XY(x.Measure_Value, x.Time); }
  TGraph& graph;
};

void __fastcall TForm1::ConnectButtonClick(TObject *Sender)
{
    std::for_each(mh.begin(), mh.end(), print<S_record>(*graph1));
}

I appreciate all comments on this question even the small ones if i have used pointer or reference in the wrong way.

Thanks