How To Jump to a Particular Page in a Property Sheet.

MORE INFORMATION

The following steps illustrate how to add mnemonics to a page and how to trap the key strokes to check for the mnemonics. The sample code that follows uses a WH_GETMESSAGE hook to examine the keys pressed. If the key pressed happens to be a combination of the ALT key and the key designated for a particular page, then that page is activated.

1. When initializing the PROPSHEETHEADER structure, include the PSH_USECALLBACK flag in the dwFlags member variable, and assign a callback function to the pfnCallback member variable.
2. The callback function could be written as shown below:

         int CALLBACK PropSheetCallbackProc(HWND hwndDlg, UINT uMsg, LPARAM
            lParam)
         {
         if (uMsg == PSCB_INITIALIZED)
         {
                  g_hWndPropSheet = hwndDlg; //Store the window handle of the
                                             //property sheet in a global
                                             //variable.
                  g_hhook = SetWindowsHookEx(WH_GETMESSAGE,(HOOKPROC)hkProc,
                     NULL,GetWindowThreadProcessId(g_hWndPropSheet,NULL));
         }
   
              return 0;
          }
   						

3. When initializing the PROPSHEETPAGE structure, use the mnemonic prefix (&) in the "pszTitle" member variable to designate a letter for a particular page. This letter, when pressed in combination with the ALT key, would activate this page.

Sample Code for the Hook Filter Function

To trap the key strokes and to examine them, the hook filter function could be written as shown below:

   LRESULT CALLBACK hkProc(UINT nCode, WPARAM wParam, LPARAM lParam)
   {
   if ( nCode < 0 )
   {
      return CallNextHookEx(g_hhook,nCode,wParam,lParam);
   }

   if ( ((MSG *)lParam)->message == WM_SYSCHAR )
   {

      HWND hTabCtrl = (HWND)
   SendMessage(g_hWndPropSheet,PSM_GETTABCONTROL,0,0);
      int nCount = SendMessage(hTabCtrl,TCM_GETITEMCOUNT,0,0);

      TCHAR   buf[80],shortcutLower[3],shortcutUpper[3];
      TC_ITEM   tcItem;

      tcItem.mask = TCIF_TEXT;
      tcItem.pszText = buf;

      shortcutUpper[0] = shortcutLower[0] = _T('&');
      shortcutUpper[2] = shortcutLower[2] = _T('\0');

      for( int i = 0; i < nCount; i++ )
      {
            tcItem.cchTextMax = 79;
            SendMessage(hTabCtrl,TCM_GETITEM,i,(LONG)&tcItem);
            shortcutUpper[1] = shortcutLower[1] =
            (TCHAR) ((MSG *)lParam)->wParam;
            if ( _istlower(shortcutUpper[1]) )
               shortcutUpper[1] = _totupper(shortcutUpper[1]);
            if ( _istupper(shortcutLower[1]) )
               shortcutLower[1] = _totlower(shortcutLower[1]);


            if ( _tcsstr( buf, shortcutLower ) ||
   tcsstr(buf,shortcutUpper) )
            {
                       PropSheet_SetCurSel(g_hWndPropSheet,NULL,i);
               ((MSG *)lParam)->message = WM_NULL; // We have taken care of
                                                   // the message, so make
                                                   // it WM_NULL.
            }
         }
      }
      return CallNextHookEx(g_hhook,nCode,wParam,lParam);

    }