MFC中ScrollWindow函数用法举例

1、类h文件

#pragma once

#ifndef __AFXWIN_H__
#error "include 'pch.h' before including this file for PCH"
#endif

#include "resource.h"       // 主符号
#include "School.h"
#include <string>
#include "StringUtil.h"
using std::wstring;
using std::string;
class CMyApp :public CWinApp
{
public:
 virtual BOOL InitInstance();
};
class CMainWindow :public CFrameWnd
{
private:
 School school;
 RECT rectWindow;
 char keyBoardCh;
 int cIndex;
 /*
 每行高度
 */
 const int hPerLine = 30;
 /*行数*/
 int rowCount;
 /*客户区*/
 CRect clientRect;
public:
 CMainWindow();
protected:
 afx_msg void OnPaint();
 afx_msg void OnSize(UINT, int, int);
 afx_msg void OnChar(UINT, UINT, UINT);
 DECLARE_MESSAGE_MAP();
};

2、实现文件

#include "pch.h"
#include "framework.h"
#include "afxwinappex.h"
#include "afxdialogex.h"
#include "MFCApplication7.h"
#include "MainFrm.h"

#include "MFCApplication7Doc.h"
#include "MFCApplication7View.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#endif

CMyApp myApp;

BOOL CMyApp::InitInstance()
{
 m_pMainWnd = new CMainWindow;
 m_pMainWnd->MoveWindow(0, 0, 800, 600, 1);
 m_pMainWnd->CenterWindow(m_pMainWnd);
 m_pMainWnd->ShowWindow(m_nCmdShow);
 
 m_pMainWnd->UpdateWindow();
 return TRUE;
}
BEGIN_MESSAGE_MAP(CMainWindow, CFrameWnd)
 ON_WM_PAINT()
 ON_WM_CHAR()
 ON_WM_SIZE()
END_MESSAGE_MAP()
CMainWindow::CMainWindow()
{
 Create(NULL, TEXT("The Hello Application"), WS_OVERLAPPEDWINDOW,rectWindow);
 keyBoardCh = 'a';
 cIndex = 0;
}
void CMainWindow::OnPaint()
{
 CPaintDC dc(this);
 dc.SetBkMode(TRANSPARENT);
 /*写文本的方框*/
 CRect rectText;
 TCHAR texts[1000];
 if (keyBoardCh == 'c')
 {
  for (int i = 0;i < 2;i++)
  {
   rectText.left = 0;
   rectText.right = clientRect.right;
   rectText.top = (clientRect.Height()/ hPerLine -1)*hPerLine +(i*hPerLine);
   rectText.bottom = rectText.top + hPerLine;
   wsprintf(texts, TEXT("a%d   %d"), (cIndex + 18 +i )*hPerLine, cIndex+17+i);
   dc.DrawText(texts, -1, &rectText, DT_SINGLELINE | DT_CENTER | DT_VCENTER);
   dc.MoveTo(0, rectText.bottom);
   dc.LineTo(rectText.right, rectText.bottom);
  }
  return;
 }
 for (int i = 0;i < rowCount;i++)
 {
  rectText.left = 0;
  rectText.right = clientRect.right;
  rectText.top = i * hPerLine;
  rectText.bottom = rectText.top + hPerLine;
  wsprintf(texts, TEXT("a%d   %d"), rectText.bottom,i);
  dc.DrawText(texts, -1, &rectText, DT_SINGLELINE | DT_CENTER | DT_VCENTER);
  dc.MoveTo(0, rectText.bottom);
  dc.LineTo(rectText.right, rectText.bottom);
 }
}

void CMainWindow::OnSize(UINT, int cx, int cy)
{
 rowCount = cy / hPerLine + 20;
 clientRect.left = 0;
 clientRect.top = 0;
 clientRect.right = cx;
 clientRect.bottom = cy;
}

void CMainWindow::OnChar(UINT ch, UINT, UINT)
{
 keyBoardCh = ch;
 if (ch == 'c')
 {
  CRect rect;
  GetClientRect(&rect);
  const int rowCount = rect.Height() / hPerLine;
  RECT rt;
  rt.left = 0;
  rt.top = rect.Height() - 30-(rect.Height() - rowCount * hPerLine) + 2;
  rt.right = rect.right;
  rt.bottom = rect.Height();
  /*向上滚动一行的高度*/
  ScrollWindow(0, -30);
  cIndex++;
  /*因为初始化客户区时，客户区的高度不正好是高度的倍数，所以无效画客户区时把最后一整行和最后一个不完整的行无效化*/
  InvalidateRect(&rt);
 }
 else
 {
  Invalidate();
 }
}