動態創建窗口,并重寫窗口過程

在窗口過程中處理滾動條消息

WNDPROC pSubclassOldEditProc;
INT iVScrollPos = 0, iVTextPos = 0;

LRESULT winProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
	//獲取新設置的窗口屬性,就是獲取CNewEdit的指針,方便后面訪問m_lOldProc這個成員
	if (message == WM_VSCROLL)
	{
		//TRACE( _T("%d\n"), LOWORD(wParam));
		switch (LOWORD(wParam))
		{
			case SB_LINEDOWN:
				if (iVScrollPos != (NUMLINE - 1)) 
					iVTextPos -= 1;
				TRACE(_T("向下滾動一行\n") );
				break;
			case SB_LINEUP:
				if (iVScrollPos != 0) iVTextPos += 1;
				TRACE( _T("向上滾動一行\n"));
				break;
			case SB_PAGEUP:
				TRACE( _T("向上滾動一頁\n"));
				break;
			case SB_PAGEDOWN:
				TRACE( _T("向下滾動一頁\n"));
				break;
			case SB_THUMBPOSITION:
				CScale3DCListBox::AdjustListBox(iVScrollPos);
				break;
			case SB_THUMBTRACK:
				iVTextPos = -HIWORD(wParam);

				break;
			default:
				break;
		}

		iVScrollPos = -iVTextPos;
		SetScrollPos(hwnd, SB_VERT, iVScrollPos, TRUE);
	}
	//處理完需要截獲(改變)的消息后接著返回舊的窗口過程
	return CallWindowProc((WNDPROC)pSubclassOldEditProc, hwnd, 
	       message, wParam, lParam);
}

創建窗口并替換過程函數,如下

m_pWndListBoxDlg = new CWnd;
LPCTSTR lpszClassName = AfxRegisterWndClass(CS_HREDRAW | CS_VREDRAW,
		AfxGetApp()->LoadStandardCursor(IDC_ARROW),
		(HBRUSH)GetStockObject(LTGRAY_BRUSH), NULL);
m_pWndListBoxDlg->Create(lpszClassName, _T(""), WS_CHILD | WS_VISIBLE| 
                WS_VSCROLL| ES_AUTOHSCROLL,
		rt1, parentWnd, 5234);

m_uID     = 5234;
m_nHeight = nHeight;

//設置滾動條
m_hwndListbox = m_pWndListBoxDlg->GetSafeHwnd();
m_pWndListBoxDlg->SetScrollRange(SB_VERT, 0, NUMLINE - 1, FALSE);
//設置 TRUE 滾動條立即重繪 這樣才能看到新位置  
m_pWndListBoxDlg->SetScrollPos(SB_VERT, 0, TRUE);
//更換窗口過程
pSubclassOldEditProc = (WNDPROC)::SetWindowLong(
      m_pWndListBoxDlg->GetSafeHwnd(), 
      GWL_WNDPROC,(DWORD)winProc);