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Visual C++

I am trying to set up a hot key of "F1" to call a routine within my software. I have been able to register the hot key but can not get the code to compile to try to take action when the hot key is pressed. I don't know how to handle WM_HOTKEY.

include windowsx.h

//this seems to be working.  if I call it a 2nd time it fails
if(!RegisterHotKey(NULL, IDC_OP_START, 0, 0x70)) MessageBox("F1 Register Failed");

WPARAM wParam;
LPARAM lParam;

void COpui::OnStartTest()
//my routine in here

error C2046: illegal case
error 'HANDLE_WM_HOTKEY' : undeclared identifier

Seems like the HANDLE_MSG function does not like me passing WM_HOTKEY.
Posted 30-Nov-12 11:29am
Updated 30-Nov-12 11:56am
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Solution 2

I think you need to spend some time learning about Windows programming before trying such advanced topics as this. You cannot just dump a case statement in the middle of your code and expect it to do something. The HANDLE_MSG macro is designed to be used inside a switch {} block in the windows message handler function of your program.
Albert Holguin 1-Dec-12 22:34pm
I agree... learn to do the windows message handling and you'll understand this much better... +5 Richard
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Solution 1

You are not showing source code which causes this problem. The identifier HANDLE_WM_HOTKEY, is not found, but the source code you show uses WM_HOTKEY which will be compiled with "windows.h":[^].

Compare:[^]. HANDLE_MSG is the macro used to implement window procedure (in a lame C++ way, in my opinion :-)):[^],[^].


In response to the follow-up question: yes, this token-pasting '##' operator you never mentioned before. It is explained here:[^].

All this preprocessor activity and this way of message handling is such a lame! Can I unsee it? :-)

denso1 30-Nov-12 17:12pm
I am not making a reference to HANDLE_WM_HOTKEY. It seems like the HANDLE_MSG is doing that on its own. I am using WINDOWSX.h file and it has the HANDLE_MSG function defined as follows:

<pre lang="cs">/****** Message crackers ****************************************************/

#define HANDLE_MSG(hwnd, message, fn) \
case (message): return HANDLE_##message((hwnd), (wParam), (lParam), (fn))</pre>

I think maybe the "return HANDLE_##message" is somehow causing my problem.

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