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COM from scratch - PART TWO

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17 Apr 200414 min read 226.5K   6K   134  
An article about COM Library.
// ComDemoView.cpp : implementation of the CComDemoView class
//

#include "stdafx.h"
#include "ComDemo.h"
//#include"C:\\Documents and Settings\\Aria\\Desktop\\DemoDll\\ComDemo\\Comp1\\Registry.h"
//#include"..\\ComDemo\\Comp1\\interface.h"
//#include"..\\ComDemo\\Comp2\\interface.h"
#include"..\\ComDemo\\Comp3\\interface.h"

#include "ComDemoDoc.h"
#include "ComDemoView.h"
#include <objbase.h>
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

//interface pointers for accesseing Component1
IUnknown*    g_pIUnknown1=NULL;
IComponent1* g_pIComponent1=NULL;

//interface pointers for accesseing Compoenen2
IUnknown*    g_pIUnknown2=NULL;
IComponent2* g_pIComponent2=NULL;


//interface pointers for accesseing Compoenen3
IUnknown*    g_pIUnknown3=NULL;
IComponent3* g_pIComponent3=NULL;




/////////////////////////////////////////////////////////////////////////////
// CComDemoView

IMPLEMENT_DYNCREATE(CComDemoView, CView)

BEGIN_MESSAGE_MAP(CComDemoView, CView)
	//{{AFX_MSG_MAP(CComDemoView)
	ON_COMMAND(ID_COMP2, OnComp2)
	ON_WM_LBUTTONDOWN()
	ON_WM_TIMER()
	ON_COMMAND(ID_COMP1, OnComp1)
	ON_COMMAND(ID_COMP3, OnComp3)
	ON_COMMAND(ID_SHOW, OnShow)
	//}}AFX_MSG_MAP
	// Standard printing commands
	ON_COMMAND(ID_FILE_PRINT, CView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_DIRECT, CView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_PREVIEW, CView::OnFilePrintPreview)
    //ON_MESSAGE(WM_RELEASE,OnRelease)

	END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CComDemoView construction/destruction

CComDemoView::CComDemoView()
{
	// TODO: add construction code here
	
}

CComDemoView::~CComDemoView()
{
}

BOOL CComDemoView::PreCreateWindow(CREATESTRUCT& cs)
{
	// TODO: Modify the Window class or styles here by modifying
	//  the CREATESTRUCT cs

	return CView::PreCreateWindow(cs);
}

/////////////////////////////////////////////////////////////////////////////
// CComDemoView drawing

void CComDemoView::OnDraw(CDC* pDC)
{
	CComDemoDoc* pDoc = GetDocument();
	ASSERT_VALID(pDoc);
	// TODO: add draw code for native data here
CBrush brush;
brush.CreateSolidBrush(RGB(0,0,0));
CRect rect;
GetClientRect(&rect);
pDC->FillRect(&rect,&brush);
}

/////////////////////////////////////////////////////////////////////////////
// CComDemoView printing

BOOL CComDemoView::OnPreparePrinting(CPrintInfo* pInfo)
{
	// default preparation
	return DoPreparePrinting(pInfo);
}

void CComDemoView::OnBeginPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
	// TODO: add extra initialization before printing
}

void CComDemoView::OnEndPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
	// TODO: add cleanup after printing
}

/////////////////////////////////////////////////////////////////////////////
// CComDemoView diagnostics

#ifdef _DEBUG
void CComDemoView::AssertValid() const
{
	CView::AssertValid();
}

void CComDemoView::Dump(CDumpContext& dc) const
{
	CView::Dump(dc);
}

CComDemoDoc* CComDemoView::GetDocument() // non-debug version is inline
{
	ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CComDemoDoc)));
	return (CComDemoDoc*)m_pDocument;
}
#endif //_DEBUG

/////////////////////////////////////////////////////////////////////////////
// CComDemoView message handlers


////////////////////////////
void CComDemoView::OnComp1()
{
    
    CString str;
    int i;
    CStdioFile fr;
    //Not allow creation of the component more than one
    fr.Open("C:\\Comp1IUnknown.txt",CFile::modeRead);
    fr.ReadString(str);
    fr.Close();
    i=atoi(str);
    
    if(i==0)// 0 means component1 is not created
    {
        
        
        //CoInitialize(NULL); is called in the InitInstance() function at the start of the program
        HRESULT hr = ::CoCreateInstance(CLSID_Component1,NULL,CLSCTX_INPROC_SERVER,IID_IUnknown,(void**)&g_pIUnknown1) ;
        
        if (SUCCEEDED(hr))
        {
            TRACE(_T("Succeeded getting IComponent1.\n")) ;
            CStdioFile fw;
            COLORREF color=RGB(0,255,255);
            hr=g_pIUnknown1->QueryInterface(IID_IComponent1,(void**)&g_pIComponent1);
            if(SUCCEEDED(hr))
            {
                g_pIComponent1->DefineWindow_Com1(false);
                g_pIComponent1->ShowWndBackground_Com1(color);
                
                fw.Open ("C:\\Comp1IUnknown.txt",CFile::modeWrite);
                fw.WriteString ("1");// not possible to make more componet1 until the one which is already created is released
                fw.Close();
            }
            SetTimer(1,100,NULL);// checking the clients acions every 100 ms
        }
        else
        {
            TRACE(_T("Component1 creation failed"));
            AfxMessageBox("Build the dlls and move them in the folder 'C:\\Codeproject' and activate the registeration file(registerdlls.reg)");
        }
    }
}


////////////////////////////
void CComDemoView::OnComp2() 
{
	CString str;
int i;
CStdioFile fr;
fr.Open("C:\\Comp2IUnknown.txt",CFile::modeRead);
fr.ReadString(str);
fr.Close();
i=atoi(str);
if(i==0)
{
    
    //CoInitialize(NULL); is called in the ExitINstance() function at the end of the program
    HRESULT hr = ::CoCreateInstance(CLSID_Component2,NULL,CLSCTX_INPROC_SERVER,IID_IUnknown,(void**)&g_pIUnknown2) ;
    
    if (SUCCEEDED(hr))
    {
        TRACE(_T("Succeeded getting IComponent2.\n")) ;
        CStdioFile fw;
        COLORREF color=RGB(255,255,255);
        hr=g_pIUnknown2->QueryInterface(IID_IComponent2,(void**)&g_pIComponent2);
        
        if(SUCCEEDED(hr))
        {
            g_pIComponent2->DefineWindow_Com2(false);
            g_pIComponent2->ShowWndBackground_Com2(color);
            //g_pIComponent2->StopFlying();
            fw.Open ("C:\\Comp2IUnknown.txt",CFile::modeWrite);
            fw.WriteString ("1");
            fw.Close();
        }
        
        SetTimer(1,100,NULL);
    }
    else
    {
        TRACE(_T("Component2 creation failed"));
        AfxMessageBox("Build the dlls and move them in the folder 'C:\\Codeproject' and activate the registeration file(registerdlls.reg)");
    }
}
}


	




////////////////////////////////////////////////////////////
void CComDemoView::OnLButtonDown(UINT nFlags, CPoint point) 
{
    CString str;
	CStdioFile fr;
	fr.Open("C:\\Comp1IUnknown.txt",CFile::modeRead);
	fr.ReadString(str);
	fr.Close();
	if(str!="0")
	{
		if(NULL!=g_pIComponent1)
		g_pIComponent1->MenuitemNotselected1();
	}
	fr.Open("C:\\Comp2IUnknown.txt",CFile::modeRead);
	fr.ReadString(str);
	fr.Close();
	if(str!="0")
	{
		if(NULL!=g_pIComponent2)
		g_pIComponent2->MenuitemNotselected2();
	}
	
	
	CView::OnLButtonDown(nFlags, point);
}



//--------------------------------------------------------------------//
// This function checks out  menu item selections from the components
// windows and  the corresponding methods belonging to the components 
// will be called.
//--------------------------------------------------------------------//
void CComDemoView::OnTimer(UINT nIDEvent)
{
    CString str;
    int i;
    CStdioFile fr;
    
    
    //Checking out the menu item selection for componenet1 and response to that
    fr.Open("C:\\Comp1Notifyclient.txt",CFile::modeRead);
    fr.ReadString(str);
    fr.Close();
    i=atoi(str);
    
    if(i!=0)// 1 means that the user has selected "Night();" menu item from component 1's menu,
    //and here this action takes place by calling the component Night() method.
    {
        
        if(NULL!=g_pIComponent1)
            g_pIComponent1->Night();//Calling the Night() method of Component1
        //Init the notification file  back
        str="0";
        fr.Open("C:\\Comp1Notifyclient.txt",CFile::modeWrite|CFile::typeText);
        fr.WriteString(str);
        fr.Close();
        
    }
    
    
    //Checking out the menu item selection for componenet 2 and response to that
    fr.Open("C:\\Comp2Notifyclient.txt",CFile::modeRead);
    fr.ReadString(str);
    fr.Close();
    i=atoi(str);
    
    if(i!=0)
    {
        
        if(NULL!=g_pIComponent2)
            g_pIComponent2->StartFlying();//Calling the StopFlying() method of Component2
        //intit the notification file back
        str="0";
        fr.Open("C:\\Comp2Notifyclient.txt",CFile::modeWrite|CFile::typeText);
        fr.WriteString(str);
        fr.Close();
        
    }
    
    
    //Checking out the menu item selection for componenet 3 and response to that
    fr.Open("C:\\Comp3Notifyclient.txt",CFile::modeRead);
    fr.ReadString(str);
    fr.Close();
    i=atoi(str);
    COLORREF whitecolor=RGB(0,0,0);
    
    switch(i)
    {
        // 1 is coded to call the Night() method of the inner component1
        case 1:
            if(NULL!=g_pIComponent3)
                g_pIComponent3->Night();
            break;
            
            // 2 is coded to call the StartFlying method of the inner component2
        case 2:
            if(NULL!=g_pIComponent3)
                //calling the ShowWndBackground_Com2 once more in order to whipe the
                // window before flying
                g_pIComponent3->ShowWndBackground_Com2(whitecolor);
            g_pIComponent3->StartFlying();
            break;
            
            // 3 is coded to call the StopFlying method of the inner component2
        case 3:
            if(NULL!=g_pIComponent3)
                g_pIComponent3->StopFlying();
            break;
    }
    
    //initialize the notification file
    str="0";
    fr.Open("C:\\Comp3Notifyclient.txt",CFile::modeWrite|CFile::typeText);
    fr.WriteString(str);
    fr.Close();
    
    CView::OnTimer(nIDEvent);
}




////////////////////////////
void CComDemoView::OnComp3()
{
    
    CString str;
    int i;
    CStdioFile fr;
    fr.Open("C:\\Comp3IUnknown.txt",CFile::modeRead);
    fr.ReadString(str);
    fr.Close();
    i=atoi(str);
    if(i==0)
    {
        HRESULT hr = ::CoCreateInstance(CLSID_Component3,
        NULL,
        CLSCTX_INPROC_SERVER,
        IID_IComponent3,
        (void**)&g_pIUnknown3) ;
        
        if (SUCCEEDED(hr))
        {
            TRACE(_T("Succeeded getting IComponent3.\n")) ;
            COLORREF color=RGB(0,255,255);
            hr=g_pIUnknown3->QueryInterface(IID_IComponent3,(void**)&g_pIComponent3);
            if(SUCCEEDED(hr))
            {
                //Outer Component, Component3
                g_pIComponent3->DefineWindow_Com3();
                g_pIComponent3->ShowWndBackground_Com3(color);
                
                //Inner Component1
                g_pIComponent3->DefineWindow_Com1(true);
                g_pIComponent3->ShowWndBackground_Com1(color);
                
                //Inner Component2
                g_pIComponent3->DefineWindow_Com2(true);
                g_pIComponent3->ShowWndBackground_Com2(color);
                
                fr.Open ("C:\\Comp3IUnknown.txt",CFile::modeWrite);
                fr.WriteString ("1");
                fr.Close();
                SetTimer(1,100,NULL);
            }
            
        }
        
        else
        {
            AfxMessageBox("Build the dlls and move them in the folder 'C:\\Codeproject' and activate the registeration file(registerdlls.reg)");
            TRACE(_T("Component3 creation failed"));
            
        }
        
    }
}




///////////////////////////
void CComDemoView::OnShow() 
{
	// TODO: Add your command handler code here
	CRect rect;
	GetClientRect(&rect);
	CBitmap bmp, *poldbmp;
	CDC memdc;           
	CClientDC dc(this);
	bmp.LoadBitmap("IDB_COM" );
	// Create a compatible memory DC
	memdc.CreateCompatibleDC( &dc );
	// Select the bitmap into the DC
	poldbmp = memdc.SelectObject( &bmp );
	// Copy (BitBlt) bitmap from memory DC to screen DC
	dc.BitBlt(rect.left ,rect.top , rect.Width() , rect.Height() , &memdc, 0, 0, SRCCOPY );
	memdc.SelectObject( poldbmp ); 
}

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Written By
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Denmark Denmark
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