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Is it possible to use keyboard shortcuts to navigate the individual tab items (pages) of the CExtTabWnd control?

if you have a shortcut like this, La&yout, for one of the tab pages then on pressing Alt+y it doesnt invoke that page. If however you rename it as
La&Yout then it works and selects the appropriate page.

Thank you for reporting this issue. To fix it, please update the following method’s source code:

INT CExtTabWnd::ItemFindByAccessChar(
      __EXT_MFC_SAFE_TCHAR chrAccess,
      INT nStartIdx, // = -1
      BOOL bRestartAt0 // = TRUE
      ) const
{
      ASSERT_VALID( this );
      if( chrAccess == _T(’0’) )
            return -1;
TCHAR szChar[2] = { chrAccess, _T(’\0’) };
      ::CharUpper( szChar );
int cAccelSearch = szChar[0];
      if( cAccelSearch == _T(’\0’) )
            return -1;
LONG nCount = ItemGetCount();
LONG nIdx = ( nStartIdx >= 0L ) ? ( nStartIdx + 1L ) : 0L;
      if( nIdx >= nCount && bRestartAt0 )
            nIdx = 0L;
      for( ; nIdx < nCount; nIdx++ )
      {
            const TAB_ITEM_INFO * pTII = ItemGet( nIdx );
            ASSERT_VALID( pTII );
            if( ! pTII->VisibleGet() )
                  continue;
            if( ! pTII->EnabledGet() )
                  continue;
            CExtSafeString str = pTII->TextGet();
            if( str.IsEmpty() )
                  continue;
            INT nPos = str.Find( _T("&") );
            if(         nPos < 0
                  ||    nPos == (str.GetLength() - 1)
                  )
                  continue;
            ++ nPos;
            TCHAR szAccel[2] = { str.GetAt( nPos ), _T(’\0’) };
            ::CharUpper( szAccel );
            if( szAccel[0] == _T(’\0’) )
                  return -1;
            if( cAccelSearch == szAccel[0] )
            {
                  if( nStartIdx != nIdx )
                        return nIdx;
            }
      } // for( nIdx = nStartIdx; nIdx < nCount; nIdx++ )
      if( nStartIdx == 0 )
            return -1;
      for( nIdx = 0; nIdx<nStartIdx; nIdx++ )
      {
            const TAB_ITEM_INFO * pTII = ItemGet( nIdx );
            ASSERT_VALID( pTII );
            if( ! pTII->VisibleGet() )
                  continue;
            if( ! pTII->EnabledGet() )
                  continue;
            CExtSafeString str = pTII->TextGet();
            if( str.IsEmpty() )
                  continue;
            INT nPos = str.Find( _T("&") );
            if(         nPos < 0
                  ||    nPos == (str.GetLength() - 1)
                  )
                  continue;
            ++ nPos;
            TCHAR szAccel[2] = { str.GetAt( nPos ), _T(’\0’) };
            ::CharUpper( szAccel );
            if( szAccel[0] == _T(’\0’) )
                  return -1;
            if( cAccelSearch == szAccel[0] )
            {
                  if( nStartIdx != nIdx )
                        return nIdx;
            }
      } // for( nIdx = 0; nIdx<nStartIdx; nIdx++ )
      return -1;
}

This works fine except for the fact that there is bug in CExtTabWnd::ItemFindByAccessChar which doesnt handle lower case keyboard shortcuts correctly.

The code snippet in our previous message is exactly the same as in the tab page container control. Please provide us with more details about what is working incorrectly with lower case keyboard shortcuts? Which language is used in tab items? Which language is selected when the problem occurs?

ok I see that you mention the ItemFindByAccessChar method but how do I use it with the CExtTabWnd control?

My question was for navigating the pages of the CExtTabWnd control not the CExtTabPageContainerWnd which has this feature. How do I implement the same for CExtTabWnd.

You should pre-translate keyboard messages in your main frame or dialog window using the following code:

      if(         WM_KEYFIRST <= pMsg->message
            &&    pMsg->message <= WM_KEYLAST
            &&    ( ! CExtPopupMenuWnd::IsKeyPressed( VK_SHIFT ) )
            &&    ( ! CExtPopupMenuWnd::IsKeyPressed( VK_CONTROL ) )
            &&    CExtPopupMenuWnd::IsKeyPressed( VK_MENU )
            )
      {
            CExtTabWnd * pWndTabs = . . .;
            if( pWndTabs->GetSafeHwnd() != NULL )
            {
                  UINT nChar = UINT( pMsg->wParam );
                  ASSERT_VALID( pWndTabs );
                  BYTE lpKeyState[256];
                  ::GetKeyboardState( lpKeyState );
                  UINT wScanCode = ::MapVirtualKey( nChar, 0 );
                  HKL hKeyboardLayout =
                        ::GetKeyboardLayout(
                              ( ::AfxGetThread() ) -> m_nThreadID
                              );
#if (defined _UNICODE)
                  TCHAR szChar[2] = { _T(’\0’), _T(’\0’) };
                  ::ToUnicodeEx(
                        nChar,
                        wScanCode,
                        lpKeyState,
                        szChar, 1,
                        1,
                        hKeyboardLayout
                        );
                  WORD nMapped = WORD( szChar[0] );
#else
                  WORD nMapped = 0;
                  ::ToAsciiEx(
                        nChar,
                        wScanCode,
                        lpKeyState,
                        &nMapped,
                        1,
                        hKeyboardLayout
                        );
#endif
                  LONG nPrevIdx = pWndTabs->SelectionGet();
                  LONG nNextIdx =
                        pWndTabs->ItemFindByAccessChar(
                              (TCHAR)nMapped,
                              nPrevIdx
                              );
                  if( nNextIdx >= 0 && nNextIdx != nPrevIdx )
                  {
                        pWndTabs->SelectionSet( nNextIdx, true, true );
                        return TRUE;
                  } // if( nNextIdx >= 0 && nNextIdx != nPrevIdx )
            } // if( pWndTabs->GetSafeHwnd() != NULL )
      } // if( WM_KEYFIRST <= pMsg->message ...

This feature is available starting from v.2.70. The CExtTabPageContainer::m_bAllowAccelBasedPageSelection allows you to select tabs in tabbed page containers by using keyboard shortcuts. There is also a CExtTabWnd::ItemFindByAccessChar() method, which allows you to get the item by a shortcut character.