I hope you don't mind, but I've a bit more information on this:
Reading the documentation closer, I see that Boost acknowledges that any serialized pointer is deserialized with a new keyword: "Serialization of pointers is implemented in the library with code similar to the following:"
// load data required for construction and invoke constructor in place
template<class Archive, class T>
inline void load_construct_data(
Archive & ar, T * t, const unsigned int file_version
){
// default just uses the default constructor to initialize
// previously allocated memory.
::new(t)T();
}
The documentation recommends overloading this function if necessary:
template<class Archive>
inline void load_construct_data(
Archive & ar, my_class * t, const unsigned int file_version
){
// retrieve data from archive required to construct new instance
int attribute;
ar >> attribute;
// invoke inplace constructor to initialize instance of my_class
::new(t)my_class(attribute);
}
But this would again result in needed to implement a CMyDoc copy constructor.
Any help very much appreciated - thank you.
Hi All,
I'm porting an existing MFC C++ application to use Boost::Serialization for XML files. My CDocument object contains all the data for the app. I've implemented the serialize function as:
template<class Archive>
void CMyDoc::serialize(Archive& ar, const unsigned int version)
{
ar & BOOST_SERIALIZATION_NVP(m_Param1)
& BOOST_SERIALIZATION_NVP(m_Param2);
}
To capture the save and load events, in the CMyDoc.cpp file I have:
BOOL CMyDoc::OnOpenDocument(LPCTSTR lpszPathName)
{
clear(); // clear current params
//if (!CDocument::OnOpenDocument(lpszPathName)) // Old MFC serialize code
// return FALSE;
CEvolveTrafficDoc* pDoc = this; // pointers the same here
std::ifstream ifs(lpszPathName);
boost::archive::xml_iarchive ia(ifs);
ia >> boost::serialization::make_nvp("MyDoc",pDoc); // pointer changes here
return TRUE;
}
BOOL CMyDoc::OnSaveDocument(LPCTSTR lpszPathName)
{
//if (!CDocument::OnSaveDocument(lpszPathName)) // Old MFC serialize code
// return FALSE;
std::ofstream ofs(lpszPathName);
boost::archive::xml_oarchive oa(ofs);
oa << boost::serialization::make_nvp("MyDoc",this);
return TRUE;
}
Saving a document works fine. The problem is that loading a document doesn't work. The boost library seems to copy the CMyDoc object because the pointer comes back a different address. This means that the loaded file isn't loaded into the current document. Can a CDoc overwrite itself with boost? It can with MFC CArchive.
If I overload the CMyView to capture the file open and save events, the MRU list management offered by the Doc/View architecture won't happen.
I'm sure this has been done a million times, but I can't find any information online. Weird! Any help much appreciated.
Thanks,
Colin