🚀 go-pugleaf

In article <1992Dec19.022439.8466@emr1.emr.ca> jagrant@emr1.emr.ca (John Grant) writes:
>My app behaves a bit like a MDI app, but not quite.  From the main
>window, several other parentless non-child windows can be created as
>follows:
>	CreateWindow("xxx",NULL,
>			WS_OVERLAPPED  | WS_CAPTION    |
>			WS_SYSMENU     | WS_THICKFRAME |
>			WS_MINIMIZEBOX | WS_MAXIMIZEBOX,
>			CW_USEDEFAULT,CW_USEDEFAULT,
>			CW_USEDEFAULT,CW_USEDEFAULT,
>			NULL,           //note - no parent
>			NULL,                           
>			hinstance,(LPVOID)xxx);
>
>Note: they have *no parent* and they are *not* WS_CHILD.
>
>When I close the application from the main window, these secondary
>windows do not receive WM_DESTROY (I breakpointed WM_DESTROY and
>it never gets there).  I guess the main window only sends WM_DESTROY
>messages to them if they have a parent and/or if they are WS_CHILD?
>Is that right?
>
>So, when I process WM_DESTROY for the main window, I want to find
>all of the secondary windows and shut them down too (so they can
>de-allocate their resources).  I tried doing this when I get
>WM_DESTROY for the main window:
>
>  void DestroySecondaryWindows(void){
>  HWND hwnd;
>	while((hwnd=FindWindow("xxx",NULL)){
>	  SendMessage(hwnd,WM_DESTROY,0,0);
>	}
>	return;
>  }
>
>Well, close but not quite.  The secondary window receives several
>WM_DESTROY messages, even though I am using 'Send' instead of 'Post'.
>I guess I need to wait until each window is destroyed before I
>try to 'find' another one?  If so, how?  
>
>I had a glance at GetWindow, but I'm a bit confused by it - should
>I be using GetWindow instead of FindWindow?  The problem is that the
>secondary windows have *no parent*.
>
I'd use:

PostMessage(hWnd,WM_CLOSE,0,0L);

instead of your SendMessage.  Additionally you can now redefine the WM_CLOSE
command to do other stuff like ask the user for confirmation.  If you don't
redefine it, it calls DestroyWindow, which is what you want.  -Rick

>-- 
>John A. Grant						jagrant@emr1.emr.ca
>Airborne Geophysics
>Geological Survey of Canada, Ottawa