childview.cpp

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// ChildView.cpp : implementation of the CChildView class
//

#include "stdafx.h"
#include "Shapes.h"
#include "ChildView.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CChildView

CChildView::CChildView()
{
	m_nShape = 1; // Triangle
}

CChildView::~CChildView()
{
}

BEGIN_MESSAGE_MAP(CChildView,CWnd )
	//{{AFX_MSG_MAP(CChildView)
	ON_WM_PAINT()
	ON_COMMAND(ID_SHAPE_CIRCLE, OnShapeCircle)
	ON_COMMAND(ID_SHAPE_TRIANGLE, OnShapeTriangle)
	ON_COMMAND(ID_SHAPE_SQUARE, OnShapeSquare)
	ON_UPDATE_COMMAND_UI(ID_SHAPE_CIRCLE, OnUpdateShapeCircle)
	ON_UPDATE_COMMAND_UI(ID_SHAPE_TRIANGLE, OnUpdateShapeTriangle)
	ON_UPDATE_COMMAND_UI(ID_SHAPE_SQUARE, OnUpdateShapeSquare)
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CChildView message handlers

BOOL CChildView::PreCreateWindow(CREATESTRUCT& cs) 
{
	if (!CWnd::PreCreateWindow(cs))
		return FALSE;

	cs.dwExStyle |= WS_EX_CLIENTEDGE;
	cs.style &= ~WS_BORDER;
	cs.lpszClass = AfxRegisterWndClass(CS_HREDRAW|CS_VREDRAW|CS_DBLCLKS, 
		::LoadCursor(NULL, IDC_ARROW), HBRUSH(COLOR_WINDOW+1), NULL);

	return TRUE;
}

void CChildView::OnPaint() 
{
	CPoint points[3];
	CPaintDC dc(this);
	
	CRect rcClient;
	GetClientRect (&rcClient);

	int cx = rcClient.Width () / 2;
	int cy = rcClient.Height () / 2;
	CRect rcShape (cx - 45, cy - 45, cx + 45, cy + 45);

	CBrush brush (RGB (255, 0, 0));
	CBrush* pOldBrush = dc.SelectObject (&brush);

	switch (m_nShape) {	

	case 0: // Circle
		dc.Ellipse (rcShape);
		break;

	case 1: // Triangle
		points[0].x = cx - 45;
		points[0].y = cy + 45;
		points[1].x = cx;
		points[1].y = cy - 45;
		points[2].x = cx + 45;
		points[2].y = cy + 45;
		dc.Polygon (points, 3);
		break;

	case 2: // Square
		dc.Rectangle (rcShape);
		break;
	}
	dc.SelectObject (pOldBrush);
}

void CChildView::OnShapeCircle() 
{
	m_nShape = 0;
	Invalidate ();	
}

void CChildView::OnShapeTriangle() 
{
	m_nShape = 1;
	Invalidate ();	
}

void CChildView::OnShapeSquare() 
{
	m_nShape = 2;
	Invalidate ();	
}

void CChildView::OnUpdateShapeCircle(CCmdUI* pCmdUI) 
{
	pCmdUI->SetCheck (m_nShape == 0);	
}

void CChildView::OnUpdateShapeTriangle(CCmdUI* pCmdUI) 
{
	pCmdUI->SetCheck (m_nShape == 1);	
}

void CChildView::OnUpdateShapeSquare(CCmdUI* pCmdUI) 
{
	pCmdUI->SetCheck (m_nShape == 2);	
}