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POPointer initialization in constructors
 

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    <p>I am developing a client-database using MFC and lately I was trying to create a class in order to perform DAO operations (instead of implementing these operations directly at the <code>CDocument</code> class). I named this class as <code>CModel</code>, and <code>CDocument</code> contains it. In order to perform SQL operations using the <code>CModel</code> class, I must have access to the <code>m_session</code> variable - which represents a database access session - and it can be found in the RecordSet class - which represent one table in a database of mine. Here is a piece of code to better illustrate the situation:</p> <pre><code>#pragma once #include "MFCApplicationSet.h" class CModel { public: CModel(CMFCApplicationSet ApplicationSet); ~CModel(); CMFCApplicationSet * pModelSet; } // Model.cpp : implementation file // #include "stdafx.h" #include "MFCApplication.h" #include "Model.h" #include "SQLQuery.h" #include "MFCApplicationSet.h" #ifdef _DEBUG #define new DEBUG_NEW #endif CModel::CModel(CMFCApplicationSet ApplicationSet) { pModelSet = &amp;ApplicationSet //not sure if it is right } CModel::~CModel() { } // MFCApplicationDoc.h : interface of the CMFCApplicationDoc class #pragma once #include "MFCApplicationSet.h" #include "Model.h" class CMFCApplicationDoc : public CDocument { protected: // create from serialization only CMFCApplicationDoc(); DECLARE_DYNCREATE(CMFCApplicationDoc) // Attributes public: CMFCApplicationSet m_MFCApplicationSet; CModel Model; } // MFCApplicationDoc.cpp : implementation of the CMFCApplicationDoc class // #include "stdafx.h" #ifndef SHARED_HANDLERS #include "MFCApplication.h" #endif #include "MFCApplicationSet.h" #include "MFCApplicationDoc.h" #include "Model.h" #ifdef _DEBUG #define new DEBUG_NEW #endif IMPLEMENT_DYNCREATE(CMFCApplicationDoc, CDocument) BEGIN_MESSAGE_MAP(CMFCApplicationDoc, CDocument) END_MESSAGE_MAP() // CMFCApplicationDoc construction/destruction CMFCApplicationDoc::CMFCApplicationDoc() { //problem in implementing a instruction to call the Model object constructor } CMFCApplicationDoc::~CMFCApplicationDoc() { } </code></pre> <p>I've used the debugger to analyse my code flow and I noticed that, from the <code>CMFCApplicationDoc</code> constructor (<code>CDocument</code>), the constructor from each variable declared in the <code>CMFCApplicationDoc.h</code> is initialized. Here's my problem: I've tried to create a <code>CModel</code> constructor in order to the <code>pModelSet</code> pointer automatically reference the variable <code>m_MFCApplicationSet</code> (check the constructor arguments) declared in the <code>Doc</code> class, but I am experiencing some trouble in giving this instruction inside the construction of the <code>Doc</code> class. Is there a specific or maybe an alternative way to do this? (sorry if this task is kind of elementary, but I am still very newbie in C++)</p>
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