scribvw.cpp

最后一步了 终于实现了所有的基本功能了 可以画线 保存 打开 重绘 还有打印 最好能看着书 上面有很详细的讲解 祝大家成功vc6.0实现画线第一步（深入浅出mfc）

// ScribVw.cpp : implementation of the CScribbleView class
//
// This is a part of the Microsoft Foundation Classes C++ library.
// Copyright (C) 1992-1995 Microsoft Corporation
// All rights reserved.
//
// This source code is only intended as a supplement to the
// Microsoft Foundation Classes Reference and related
// electronic documentation provided with the library.
// See these sources for detailed information regarding the
// Microsoft Foundation Classes product.

#include "stdafx.h"
#include "Scribble.h"

#include "ScribDoc.h"
#include "ScribVw.h"

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

/////////////////////////////////////////////////////////////////////////////
// CScribbleView

IMPLEMENT_DYNCREATE(CScribbleView, CScrollView)

BEGIN_MESSAGE_MAP(CScribbleView, CScrollView)
	//{{AFX_MSG_MAP(CScribbleView)
	ON_WM_LBUTTONDOWN()
	ON_WM_LBUTTONUP()
	ON_WM_MOUSEMOVE()
	//}}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)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CScribbleView construction/destruction

CScribbleView::CScribbleView()
{
	// TODO: add construction code here

}

CScribbleView::~CScribbleView()
{
}

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

	return CView::PreCreateWindow(cs);
}

/////////////////////////////////////////////////////////////////////////////
// CScribbleView drawing

void CScribbleView::OnDraw(CDC* pDC)
{
	CScribbleDoc* pDoc = GetDocument();
	ASSERT_VALID(pDoc);

	// Get the invalidated rectangle of the view, or in the case
	// of printing, the clipping region of the printer dc.
	CRect rectClip;
	CRect rectStroke;
	pDC->GetClipBox(&rectClip);
	pDC->LPtoDP(&rectClip);
	rectClip.InflateRect(1, 1); // avoid rounding to nothing

	// Note: CScrollView::OnPaint() will have already adjusted the
	// viewport origin before calling OnDraw(), to reflect the
	// currently scrolled position.

	// The view delegates the drawing of individual strokes to
	// CStroke::DrawStroke().
	CTypedPtrList<CObList,CStroke*>& strokeList = pDoc->m_strokeList;
	POSITION pos = strokeList.GetHeadPosition();
	while (pos != NULL)
	{
		CStroke* pStroke = strokeList.GetNext(pos);
		rectStroke = pStroke->GetBoundingRect();
		pDC->LPtoDP(&rectStroke);
		rectStroke.InflateRect(1, 1); // avoid rounding to nothing
		if (!rectStroke.IntersectRect(&rectStroke, &rectClip))
			continue;
		pStroke->DrawStroke(pDC);
	}
}

/////////////////////////////////////////////////////////////////////////////
// CScribbleView printing

BOOL CScribbleView::OnPreparePrinting(CPrintInfo* pInfo)
{
	pInfo->SetMaxPage(2);   // the document is two pages long:
							// the first page is the title page
							// the second is the drawing
	BOOL bRet = DoPreparePrinting(pInfo);	// default preparation
	pInfo->m_nNumPreviewPages = 2;  // Preview 2 pages at a time
	// Set this value after calling DoPreparePrinting to override
	// value read from .INI file
	return bRet;
}

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

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

/////////////////////////////////////////////////////////////////////////////
// CScribbleView diagnostics

#ifdef _DEBUG
void CScribbleView::AssertValid() const
{
	CScrollView::AssertValid();
}

void CScribbleView::Dump(CDumpContext& dc) const
{
	CScrollView::Dump(dc);
}

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

/////////////////////////////////////////////////////////////////////////////
// CScribbleView message handlers

void CScribbleView::OnLButtonDown(UINT, CPoint point) 
{
    // Pressing the mouse button in the view window starts a new stroke

	// CScrollView changes the viewport origin and mapping mode.
	// It's necessary to convert the point from device coordinates
	// to logical coordinates, such as are stored in the document.
	CClientDC dc(this);
	OnPrepareDC(&dc);
	dc.DPtoLP(&point);

	m_pStrokeCur = GetDocument()->NewStroke();
	// Add first point to the new stroke
	m_pStrokeCur->m_pointArray.Add(point);

	SetCapture();       // Capture the mouse until button up.
	m_ptPrev = point;   // Serves as the MoveTo() anchor point for the
						// LineTo() the next point, as the user drags the
						// mouse.

	return;
}

void CScribbleView::OnLButtonUp(UINT, CPoint point) 
{
	// Mouse button up is interesting in the Scribble application
	// only if the user is currently drawing a new stroke by dragging
	// the captured mouse.

	if (GetCapture() != this)
		return; // If this window (view) didn't capture the mouse,
				// then the user isn't drawing in this window.

	CScribbleDoc* pDoc = GetDocument();

	CClientDC dc(this);

	// CScrollView changes the viewport origin and mapping mode.
	// It's necessary to convert the point from device coordinates
	// to logical coordinates, such as are stored in the document.
	OnPrepareDC(&dc);  // set up mapping mode and viewport origin
	dc.DPtoLP(&point);

	CPen* pOldPen = dc.SelectObject(pDoc->GetCurrentPen());
	dc.MoveTo(m_ptPrev);
	dc.LineTo(point);
	dc.SelectObject(pOldPen);
	m_pStrokeCur->m_pointArray.Add(point);

	// Tell the stroke item that we're done adding points to it.
	// This is so it can finish computing its bounding rectangle.
	m_pStrokeCur->FinishStroke();

	// Tell the other views that this stroke has been added
	// so that they can invalidate this stroke's area in their
	// client area.
	pDoc->UpdateAllViews(this, 0L, m_pStrokeCur);

	ReleaseCapture();   // Release the mouse capture established at
						// the beginning of the mouse drag.
	return;
}

void CScribbleView::OnMouseMove(UINT, CPoint point) 
{
	// Mouse movement is interesting in the Scribble application
	// only if the user is currently drawing a new stroke by dragging
	// the captured mouse.

	if (GetCapture() != this)
		return; // If this window (view) didn't capture the mouse,
				// then the user isn't drawing in this window.

	CClientDC dc(this);
	// CScrollView changes the viewport origin and mapping mode.
	// It's necessary to convert the point from device coordinates
	// to logical coordinates, such as are stored in the document.
	OnPrepareDC(&dc);
	dc.DPtoLP(&point);

	m_pStrokeCur->m_pointArray.Add(point);

	// Draw a line from the previous detected point in the mouse
	// drag to the current point.
	CPen* pOldPen = dc.SelectObject(GetDocument()->GetCurrentPen());
	dc.MoveTo(m_ptPrev);
	dc.LineTo(point);
	dc.SelectObject(pOldPen);
	m_ptPrev = point;
	return;
}

void CScribbleView::OnUpdate(CView* /* pSender */, LPARAM /* lHint */, 
	CObject* pHint) 
{
	// The document has informed this view that some data has changed.

	if (pHint != NULL)
	{
		if (pHint->IsKindOf(RUNTIME_CLASS(CStroke)))
		{
			// The hint is that a stroke as been added (or changed).
			// So, invalidate its rectangle.
			CStroke* pStroke = (CStroke*)pHint;
			CClientDC dc(this);
			OnPrepareDC(&dc);
			CRect rectInvalid = pStroke->GetBoundingRect();
			dc.LPtoDP(&rectInvalid);
			InvalidateRect(&rectInvalid);
			return;
		}
	}
	// We can't interpret the hint, so assume that anything might
	// have been updated.
	Invalidate(TRUE);
	return;
}

void CScribbleView::OnInitialUpdate() 
{
	SetScrollSizes(MM_LOENGLISH, GetDocument()->GetDocSize());
	CScrollView::OnInitialUpdate();
}

void CScribbleView::OnPrint(CDC* pDC, CPrintInfo* pInfo) 
{
	if (pInfo->m_nCurPage == 1)  // page no. 1 is the title page
	{
		PrintTitlePage(pDC, pInfo);
		return; // nothing else to print on page 1 but the page title
	}
	CString strHeader = GetDocument()->GetTitle();

	PrintPageHeader(pDC, pInfo, strHeader);
	// PrintPageHeader() subtracts out from the pInfo->m_rectDraw the
	// amount of the page used for the header.

	pDC->SetWindowOrg(pInfo->m_rectDraw.left,-pInfo->m_rectDraw.top);

	// Now print the rest of the page
	OnDraw(pDC);
}

void CScribbleView::PrintTitlePage(CDC* pDC, CPrintInfo* pInfo)
{
	// Prepare a font size for displaying the file name
	LOGFONT logFont;
	memset(&logFont, 0, sizeof(LOGFONT));
	logFont.lfHeight = 75;  //  3/4th inch high in MM_LOENGLISH
							// (1/100th inch)
	CFont font;
	CFont* pOldFont = NULL;
	if (font.CreateFontIndirect(&logFont))
		pOldFont = pDC->SelectObject(&font);

	// Get the file name, to be displayed on title page
	CString strPageTitle = GetDocument()->GetTitle();

	// Display the file name 1 inch below top of the page,
	// centered horizontally
	pDC->SetTextAlign(TA_CENTER);
	pDC->TextOut(pInfo->m_rectDraw.right/2, -100, strPageTitle);

	if (pOldFont != NULL)
		pDC->SelectObject(pOldFont);
}

void CScribbleView::PrintPageHeader(CDC* pDC, CPrintInfo* pInfo,
	CString& strHeader)
{
	// Print a page header consisting of the name of
	// the document and a horizontal line
	pDC->SetTextAlign(TA_LEFT);
	pDC->TextOut(0,-25, strHeader);  // 1/4 inch down

	// Draw a line across the page, below the header
	TEXTMETRIC textMetric;
	pDC->GetTextMetrics(&textMetric);
	int y = -35 - textMetric.tmHeight;          // line 1/10th inch below text
	pDC->MoveTo(0, y);                          // from left margin
	pDC->LineTo(pInfo->m_rectDraw.right, y);    // to right margin

	// Subtract out from the drawing rectange the space used by the header.
	y -= 25;    // space 1/4 inch below (top of) line
	pInfo->m_rectDraw.top += y;
}