childview.cpp

MFC Windows 程序设计源代码,有实用价值

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

#include "stdafx.h"
#include "Colors.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
	m_nColor = 0; // Red
}

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)
	ON_WM_CONTEXTMENU()
	//}}AFX_MSG_MAP
	ON_COMMAND_RANGE (ID_COLOR_RED, ID_COLOR_BLUE, OnColor)
	ON_UPDATE_COMMAND_UI_RANGE (ID_COLOR_RED, ID_COLOR_BLUE, OnUpdateColor)
END_MESSAGE_MAP()

const COLORREF CChildView::m_clrColors[5] = {
	RGB ( 255,   0,   0), // Red
	RGB ( 255, 255,   0), // Yellow
	RGB (   0, 255,   0), // Green
	RGB (   0, 255, 255), // Cyan
	RGB (   0,   0, 255)  // Blue
};

/////////////////////////////////////////////////////////////////////////////
// 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 (m_clrColors[m_nColor]);
	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);	
}

void CChildView::OnColor (UINT nID)
{
	m_nColor = nID - ID_COLOR_RED;
	Invalidate ();
}

void CChildView::OnUpdateColor (CCmdUI* pCmdUI)
{
	pCmdUI->SetCheck ((int) pCmdUI->m_nID - ID_COLOR_RED == m_nColor);
}

void CChildView::OnContextMenu(CWnd* pWnd, CPoint point) 
{
    CRect rcClient;
    GetClientRect (&rcClient);

	int cx = rcClient.Width () / 2;
	int cy = rcClient.Height () / 2;
	CRect rcShape (cx - 45, cy - 45, cx + 45, cy + 45);
	
	CPoint pos = point;
	ScreenToClient (&pos);

	CPoint points[3];
	BOOL bShapeClicked = FALSE;
	int dx, dy;

	//
	// Hit test the shape.
	//
	switch (m_nShape) {

	case 0: // Circle
		dx = pos.x - cx;
		dy = pos.y - cy;
		if ((dx * dx) + (dy * dy) <= (45 * 45))
			bShapeClicked = TRUE;
		break;

	case 1: // Triangle
		if (rcShape.PtInRect (pos)) {
	        dx = min (pos.x - rcShape.left, rcShape.right - pos.x);
	        if ((rcShape.bottom - pos.y) < (2 * dx))
	            bShapeClicked = TRUE;
		}
		break;

	case 2: // Square
		if (rcShape.PtInRect (pos))
			bShapeClicked = TRUE;
		break;
	}

	//
	// Display a context menu if the shape was clicked.
	//
    if (bShapeClicked) {
        CMenu menu;
        menu.LoadMenu (IDR_CONTEXTMENU);
        CMenu* pContextMenu = menu.GetSubMenu (0);

        for (int i=0; i<5; i++)
            pContextMenu->ModifyMenu (ID_COLOR_RED + i,
                MF_BYCOMMAND | MF_OWNERDRAW, ID_COLOR_RED + i);

        pContextMenu->TrackPopupMenu (TPM_LEFTALIGN | TPM_LEFTBUTTON |
            TPM_RIGHTBUTTON, point.x, point.y, AfxGetMainWnd ());
        return;
    }

	//
	// Call the base class if the shape was not clicked.
	//
    CWnd::OnContextMenu (pWnd, point);
}