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VC++ - Line Drawing using Document / view Architecture

/*
The view class should access this data and draw a line in the view window.
Here is the program which achieves this..
*/

// cline.h
struct cline
{
CPoint startpt ;
CPoint endpt ;
} ;

// myapp.h
class myapp : public CWinApp
{
private :

CRuntimeClass *d, *f, *v ;

public :

BOOL InitInstance( ) ;
} ;

// myapp.cpp
#include <afxwin.h>
#include "cline.h"
#include "mydoc.h"
#include "myframe.h"
#include "myview.h"
#include "myapp.h"

#include "resource.h"

myapp a ;

BOOL myapp::InitInstance( )
{
d = RUNTIME_CLASS ( mydoc ) ;
f = RUNTIME_CLASS ( myframe ) ;
v = RUNTIME_CLASS ( myview ) ;

CSingleDocTemplate *t ;
t = new CSingleDocTemplate ( IDR_MAINFRAME, d, f, v ) ;

AddDocTemplate ( t ) ;
OnFileNew( ) ;

return TRUE ;
}

// mydoc.h

class mydoc : public CDocument
{
DECLARE_DYNCREATE ( mydoc )

private :

cline line ;

public :

mydoc( ) ;
cline getline( ) ;
} ;

// mydoc.cpp
#include <afxwin.h>
#include "cline.h"
#include "mydoc.h"

IMPLEMENT_DYNCREATE ( mydoc, CDocument )

mydoc::mydoc( )
{
line.startpt.x = 10 ;
line.startpt.y = 10 ;

line.endpt.x = 100 ;
line.endpt.y = 100 ;
}

cline mydoc::getline( )
{
return line ;
}

// myframe.h
class myframe : public CFrameWnd
{
DECLARE_DYNCREATE ( myframe )
} ;

// myframe.cpp
#include <afxwin.h>
#include "myframe.h"

IMPLEMENT_DYNCREATE ( myframe, CFrameWnd )

// myview.h
class myview : public CView
{
DECLARE_DYNCREATE ( myview )

public :

void OnDraw ( CDC *p ) ;
} ;

// myview.cpp
#include <afxwin.h>
#include "cline.h"
#include "mydoc.h"
#include "myview.h"

IMPLEMENT_DYNCREATE ( myview, CView )

void myview::OnDraw ( CDC *p )
{
mydoc *doc = ( mydoc * ) GetDocument( ) ;

cline printline ;
printline = doc -> getline( ) ;

p -> MoveTo ( printline.startpt ) ;
p -> LineTo ( printline.endpt ) ;
}

Output: