C++如何实现SDI程序使用CSplitterWnd创建的多个视图的动态地显示和关闭视图

为了实现该功能我们需要对CSplitterWnd进行增强，具体实现如下：

一、定义头文件
//////////////////////////////////////////////////////////////////
//
// splitex.h
class CSplitterWndEx : public CSplitterWnd
{
protected:
   int m_nHidedCol;    // hide column number, -1 if all columns
                       // are shown

public:
   CSplitterWndEx();

   void ShowColumn();
   void HideColumn(int colHide);

// ClassWizard generated virtual function overrides
   //{{AFX_VIRTUAL(CSplitterWndEx)
   //}}AFX_VIRTUAL

// Generated message map functions
protected:
   //{{AFX_MSG(CSplitterWndEx)
      // NOTE - the ClassWizard will add and remove member
      //        functions here.
      //}}AFX_MSG

    DECLARE_MESSAGE_MAP()
};

二、具体实现代码
//////////////////////////////////////////////////////////////////
//
// splitex.cpp
#include "stdafx.h"
#include "splitex.h"

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

//////////////////////////////////////////////////////////////////
/
// CSplitterWndEx

CSplitterWndEx::CSplitterWndEx() :
    m_nHidedCol(-1)
{
}

void CSplitterWndEx::ShowColumn()
{
   ASSERT_VALID(this);
   ASSERT(m_nCols < m_nMaxCols);
   ASSERT(m_nHidedCol != -1);

   int colNew = m_nHidedCol;
   m_nHidedCol = -1;
   int cxNew = m_pColInfo[m_nCols].nCurSize;
   m_nCols++;    // add a column
   ASSERT(m_nCols == m_nMaxCols);

   // fill the hidden column
   int col;
   for (int row = 0; row < m_nRows; row++)
   {
      CWnd* pPaneShow = GetDlgItem(
         AFX_IDW_PANE_FIRST + row * 16 + m_nCols);
      ASSERT(pPaneShow != NULL);
      pPaneShow->ShowWindow(SW_SHOWNA);

      for (col = m_nCols - 2; col >= colNew; col--)
      {
         CWnd* pPane = GetPane(row, col);
         ASSERT(pPane != NULL);
         pPane->SetDlgCtrlID(IdFromRowCol(row, col + 1));
      }

      pPaneShow->SetDlgCtrlID(IdFromRowCol(row, colNew));
   }

   // new panes have been created -- recalculate layout
   for (col = colNew + 1; col < m_nCols; col++)
      m_pColInfo[col].nIdealSize = m_pColInfo[col - 1].nCurSize;
   m_pColInfo[colNew].nIdealSize = cxNew;
   RecalcLayout();
}

void CSplitterWndEx::HideColumn(int colHide)
{
   ASSERT_VALID(this);
   ASSERT(m_nCols > 1);
   ASSERT(colHide < m_nCols);
   ASSERT(m_nHidedCol == -1);
   m_nHidedCol = colHide;

   // if the column has an active window -- change it
   int rowActive, colActive;
   if (GetActivePane(&rowActive, &colActive) != NULL &&
       colActive == colHide)
   {
      if (++colActive >= m_nCols)
         colActive = 0;
      SetActivePane(rowActive, colActive);
   }

   // hide all column panes
   for (int row = 0; row < m_nRows; row++)
   {
      CWnd* pPaneHide = GetPane(row, colHide);
      ASSERT(pPaneHide != NULL);
      pPaneHide->ShowWindow(SW_HIDE);
      pPaneHide->SetDlgCtrlID(
         AFX_IDW_PANE_FIRST + row * 16 + m_nCols);

      for (int col = colHide + 1; col < m_nCols; col++)
      {
         CWnd* pPane = GetPane(row, col);
         ASSERT(pPane != NULL);
         pPane->SetDlgCtrlID(IdFromRowCol(row, col - 1));
      }
   }
   m_nCols--;
   m_pColInfo[m_nCols].nCurSize = m_pColInfo[colHide].nCurSize;
    RecalcLayout();
}

BEGIN_MESSAGE_MAP(CSplitterWndEx, CSplitterWnd)
//{{AFX_MSG_MAP(CSplitterWndEx)
   // NOTE - the ClassWizard will add and remove mapping macros here.
//}}AFX_MSG_MAP
END_MESSAGE_MAP()