mydrawview.cpp

这个是我们学校用的VC++教案

// MyDrawView.cpp : implementation of the CMyDrawView class
//

#include "stdafx.h"
#include "MyDraw.h"

#include "MyDrawDoc.h"
#include "MyDrawView.h"

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

/////////////////////////////////////////////////////////////////////////////
// CMyDrawView

IMPLEMENT_DYNCREATE(CMyDrawView, CScrollView)

BEGIN_MESSAGE_MAP(CMyDrawView, CScrollView)
	//{{AFX_MSG_MAP(CMyDrawView)
	ON_WM_LBUTTONUP()
	ON_WM_MOUSEMOVE()
	ON_WM_LBUTTONDOWN()
	//}}AFX_MSG_MAP
	// Standard printing commands
	ON_COMMAND(ID_FILE_PRINT, CScrollView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_DIRECT, CScrollView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_PREVIEW, CScrollView::OnFilePrintPreview)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CMyDrawView construction/destruction

CMyDrawView::CMyDrawView()
{
	// TODO: add construction code here
	m_bDragging=false;  // 初始化拖拽标记	
	m_hCross=AfxGetApp()->LoadStandardCursor(IDC_CROSS);  // 获得十字光标句柄
}

CMyDrawView::~CMyDrawView()
{
}

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

	return CScrollView::PreCreateWindow(cs);
}

/////////////////////////////////////////////////////////////////////////////
// CMyDrawView drawing

void CMyDrawView::OnDraw(CDC* pDC)
{
	CMyDrawDoc* pDoc = GetDocument();
	ASSERT_VALID(pDoc);
	// TODO: add draw code for native data here
	int  nIndex=pDoc->GetNumLines();  // 取得线段的数量
	TRACE("nIndex1 = %d \n", nIndex);  // 调试程序用
	//循环画出每一段线段
	while(nIndex--)  // 数组下标从0到nIndex-1
	{
		TRACE("nIndex2 = %d \n", nIndex);  // 调试程序用
		pDoc->GetLine(nIndex)->DrawLine(pDC);  // 类CLine的成员函数
	}
}

/////////////////////////////////////////////////////////////////////////////
// CMyDrawView printing

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

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

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

/////////////////////////////////////////////////////////////////////////////
// CMyDrawView diagnostics

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

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

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

/////////////////////////////////////////////////////////////////////////////
// CMyDrawView message handlers

void CMyDrawView::OnLButtonUp(UINT nFlags, CPoint point) 
{
	// TODO: Add your message handler code here and/or call default
	if(m_bDragging)
	{
		m_bDragging=false;   // 清拖拽标记	
		ReleaseCapture();    // 释放鼠标，还原鼠标形状
	}
//	CScrollView::OnLButtonUp(nFlags, point);
}

void CMyDrawView::OnMouseMove(UINT nFlags, CPoint point) 
{
	// TODO: Add your message handler code here and/or call default
	if(m_bDragging)
	{
		CMyDrawDoc *pDoc=GetDocument();  // 获得文档对象的指针
		ASSERT_VALID(pDoc);  // 测试文档对象是否运行有效
		CPoint  ptOrg, ptStart, ptEnd;
		ptOrg=GetScrollPosition();  // 获得当前工作区原点的坐标
		ptStart=m_ptOrigin+ptOrg;  // 加上原点的坐标来修正线段的坐标
		ptEnd=point+ptOrg;
		pDoc->AddLine(ptStart, ptEnd);  // 加入线段到指针数组
		CClientDC   dc(this);
		dc.MoveTo(m_ptOrigin); 
		dc.LineTo(point);  // 绘制线段
		m_ptOrigin=point;  // 新的起始点
	}
//	CScrollView::OnMouseMove(nFlags, point);
}

void CMyDrawView::OnLButtonDown(UINT nFlags, CPoint point) 
{
	// TODO: Add your message handler code here and/or call default
	SetCapture();  // 捕捉鼠标
	::SetCursor(m_hCross);  // 设置十字光标
	m_ptOrigin=point;
	m_bDragging=TRUE;  // 设置拖拽标记	
//	CScrollView::OnLButtonDown(nFlags, point);
}


void CMyDrawView::OnInitialUpdate() 
{
	CScrollView::OnInitialUpdate();
	// TODO: Add your specialized code here and/or call the base class
	CSize  sizeTotal;  
	sizeTotal.cx=sizeTotal.cy=1000;  // 定义滚动视图的大小
	SetScrollSizes(MM_TEXT, sizeTotal);  // 设置滚动视图的映射模式和大小
}