🚀 go-pugleaf

In article <1992Dec13.204238.8073@ucsu.Colorado.EDU>, tylerd@rintintin.Colorado.EDU (TYLER DAVID CHARLES) writes:
|> I'll make this brief:
|> Why doesn't the following work?
|> 
|>   if (!hPrevInstance)
|>   {
|>     [normal stuff]
|>   }
|>   else
|>   //
|>   // If an instance is already running, just display it.
|>   //
|>   {
|>     if (IsIconic (hPrevInstance))
|>     {
|>       OpenIcon (hPrevInstance);
|>     }
|>     BringWindowToTop (hPrevInstance);
|>     return TRUE;                      // Or should this be FALSE?
|>   }

The routines IsIconic(), OpenIcon(), and BringWindowToTop() need window
handles, not instance handles.

Use FindWindow() (as one possibility) to obtain the window handle for the
first instance.  Assuming that you have the class name (used to register
the window class) in a variable, szClassName, you can do the following:

   .
   .
   .
   else
      {
      HWND hwnd = FindWindow(szClassName, NULL);
      if (hwnd)
         {
         if (IsIconic(hwnd))
            OpenIcon(hwnd);

         BringWindowToTop(hwnd);
         }
      else
         {
         MessageBeep(MB_OK | MB_ICONEXCLAMATION);
         MessageBox(GetFocus(), "Unable to find window of first instance",
                    NULL, MB_OK | MB_ICONEXCLAMATION);
         }

      return 0;
      }
   .
   .
   .

The return value doesn't particularly matter -- it *can* be interpreted
as an error code by the environment that spawned your application, but
Windows itself doesn't care.


----------------------------------------------------------------------------
Tom Brown               |  "She turned me into a newt...
PE Nelson Systems       |                                  ... I got better"
twbrown@pe-nelson.com   |                    Monty Python and the Holy Grail
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