Question

I have a dialog box that allows users to set hotkeys for use in a 3d program on windows. I’m using CHotKeyCtrl, which is pretty good, but doesn’t handle some keys that the users would like to use – specifically, tab and space.

The hotkey handling is smart enough to be able to fire on those keys, I just need a UI to let them be set. A control similar to CHotKeyCtrl would be ideal, but other workarounds are also appreciated.

Answer 1

One workarounds option would be to use a stock standard edit control with a message hook function.

This would allow you to trap the keyboard WM_KEYDOWN messages sent to that edit control.

The hook function would look something like this:

    LRESULT CALLBACK MessageHook(int code, WPARAM wParam, LPMSG lpMsg)     {       LRESULT lResult = 0;        if ((code >= 0) && (code == MSGF_DIALOGBOX))       {         if (lpMsg->message == WM_KEYDOWN)         {           //-- process the key down message           lResult = 1;         }       }        // do default processing if required       if (lResult == 0)       {         lResult = CallNextHookEx(MessageFilterHook, code, wParam, (LPARAM)lpMsg);       }        return lResult;     } 

The hook can then be attached to edit control when the edit control gets focus as follows:

    //-- create an instance thunk for our hook callback     FARPROC FilterProc = (FARPROC) MakeProcInstance((HOOKPROC)(MessageHook),                                                     hInstance);     //-- attach the message hook     FilterHook = SetWindowsHookEx(WH_MSGFILTER,                                   (HOOKPROC)FilterProc,                                    hInstance, GetCurrentThreadId()); 

and removed when the edit control when looses focus as follows:

    //-- remove a message hook     UnhookWindowsHookEx(MessageFilterHook); 

Using this approach every key press will be sent to the hook, provided the edit control has focus.