Menu Handle <> Window Handle?

[Elias Montoya]

Im trying to intercept menu notifications (which i do successfully) using SetWinEventHook(), however, the window that the procedure reports is not a valid Menu handle...

Heres some code:

FUNCTION WinEventFunc(BYVAL HookHandle AS LONG, BYVAL LEvent AS LONG, BYVAL hWnd AS LONG, BYVAL idObject AS LONG, BYVAL idChild AS LONG, BYVAL idEventThread AS LONG, BYVAL dwmsEventTime AS LONG) AS LONG

If IsMenu(hWnd) then Beep ' Never beeps

call ShowWindow(hwnd, %false)  ' Hides the popup

    FUNCTION = %TRUE
END FUNCTION

Any ideas?

[Elias Montoya]

Example of the issue:

#COMPILE EXE
#DIM ALL
#INCLUDE "WIN32API.INC"

FUNCTION WinEventFunc(BYVAL HookHandle AS LONG, BYVAL LEvent AS LONG, BYVAL hWnd AS LONG, BYVAL idObject AS LONG, BYVAL idChild AS LONG, BYVAL idEventThread AS LONG, BYVAL dwmsEventTime AS LONG) AS LONG
   
    IF isMenu(hWNd) THEN BEEP              ' Never beeps
    
    CALL ShowWindow(hWNd, %SW_HIDE)        ' Hides the popup menu
    
    FUNCTION = 1
END FUNCTION

CALLBACK FUNCTION ShowDIALOG1Proc()

    STATIC LHook AS DWORD
    LOCAL Result AS LONG

    SELECT CASE AS LONG CBMSG
        CASE %WM_INITDIALOG
              LHook = SetWinEventHook(%EVENT_SYSTEM_MENUPOPUPSTART, %EVENT_SYSTEM_MENUPOPUPSTART, 0, _
                                      CODEPTR(WinEventFunc), 0, 0, %WINEVENT_OUTOFCONTEXT OR %WINEVENT_SKIPOWNTHREAD)

        CASE %WM_DESTROY
              Result = UnhookWinEvent(LHook)
    END SELECT

END FUNCTION

FUNCTION PBMAIN()
    LOCAL hDlg AS DWORD

    DIALOG  NEW %HWND_DESKTOP, "SetWinEventHook", 200, 100, 200,100, %WS_POPUP OR %WS_BORDER OR %WS_DLGFRAME OR %WS_CAPTION OR _
                               %WS_SYSMENU OR %WS_MINIMIZEBOX OR %WS_CLIPSIBLINGS OR %WS_VISIBLE OR %DS_MODALFRAME, _
                               %WS_EX_WINDOWEDGE OR %WS_EX_CONTROLPARENT OR %WS_EX_TOPMOST OR %WS_EX_LEFT OR %WS_EX_LTRREADING OR _
                               %WS_EX_RIGHTSCROLLBAR, TO hDlg
    DIALOG SHOW MODAL hDlg, CALL ShowDIALOG1Proc
    
END FUNCTION

[Peter Jinks]

Hi Elias,

How's this?

#COMPILE EXE
#DIM ALL
#INCLUDE "WIN32API.INC"

%MN_GETHMENU = &H01E1

FUNCTION WinEventFunc(BYVAL HookHandle AS LONG, BYVAL LEvent AS LONG, BYVAL hWnd AS LONG, BYVAL idObject AS LONG, BYVAL idChild AS LONG, BYVAL idEventThread AS LONG, BYVAL dwmsEventTime AS LONG) AS LONG
   LOCAL hMenu AS DWORD

   hMenu = SendMessage(hWnd, %MN_GETHMENU, 0,0)
   IF IsMenu(hMenu) THEN
      BEEP
   END IF
   CALL ShowWindow(hWNd, %SW_HIDE)        ' Hides the popup menu
   EndMenu

   FUNCTION = 1
END FUNCTION

CALLBACK FUNCTION ShowDIALOG1Proc()

    STATIC LHook AS DWORD
    LOCAL Result AS LONG

    SELECT CASE AS LONG CBMSG
        CASE %WM_INITDIALOG
              LHook = SetWinEventHook(%EVENT_SYSTEM_MENUPOPUPSTART, %EVENT_SYSTEM_MENUPOPUPSTART, 0, _
                                      CODEPTR(WinEventFunc), 0, 0, %WINEVENT_OUTOFCONTEXT) 'OR %WINEVENT_SKIPOWNTHREAD)

        CASE %WM_DESTROY
              Result = UnhookWinEvent(LHook)
    END SELECT

END FUNCTION

FUNCTION PBMAIN()
    LOCAL hDlg AS DWORD

    DIALOG  NEW %HWND_DESKTOP, "SetWinEventHook", 200, 100, 200,100, %WS_POPUP OR %WS_BORDER OR %WS_DLGFRAME OR %WS_CAPTION OR _
                               %WS_SYSMENU OR %WS_MINIMIZEBOX OR %WS_CLIPSIBLINGS OR %WS_VISIBLE OR %DS_MODALFRAME, _
                               %WS_EX_WINDOWEDGE OR %WS_EX_CONTROLPARENT OR %WS_EX_TOPMOST OR %WS_EX_LEFT OR %WS_EX_LTRREADING OR _
                               %WS_EX_RIGHTSCROLLBAR, TO hDlg
    DIALOG SHOW MODAL hDlg, CALL ShowDIALOG1Proc

END FUNCTION

Note that I've removed the %WINEVENT_SKIPOWNTHREAD from the initial call, or the callback doesn't fire at all (here at least). Also, using ShowWindow in the callback hides the menu window, but doesn't prevent me clicking on items from it where they were displayed - i.e. it just gives me an invisible, but still fully active, menu. So I've added EndMenu instead, to remove it. Lastly, getting hMenu isn't really necessary for the code shown here, as EndMenu doesn't take a parameter, but I've shown it in case you want to do other things with the menu.

I hope that helps.

Regards,

Pete.

[Michael Mattias]

Code not shown (for SetWinEventHook) so I can't tell if you are trying to hide a the window from another process or from your own, but if it's your own process using a hook is kinda overkill....
WM_INITMENU

The WM_INITMENU message is sent when a menu is about to become active. It occurs when the user clicks an item on the menu bar or presses a menu key. This allows the application to modify the menu before it is displayed

WM_INITMENUPOPUP

The WM_INITMENUPOPUP message is sent when a drop-down menu or submenu is about to become active. This allows an application to modify the menu before it is displayed, without changing the entire menu

.. Oops, I see now in the SECOND post it does appear you want to 'do something' based on other processes' activity.

In that case...

The client thread that calls SetWinEventHook must have a message loop, sometimes known as a "GUI thread," in order to receive events.

Maybe the Modal dialogbox message loop is insufficient and you need a 'real' message loop associated with the calling thread.

Try changing your DIALOG SHOW to MODELESS and add a message loop and see what happens.

MCM

[Elias Montoya]

Hello Peter,

That seems to work with Dialog menus, but it fails with menus created with TrackPopupMenu. I dont seem to find any way to get the handle of menues created with TrackPopupMenu in other processes.

Michael, i will try to use the dialog handle to temporarily suibclass the target dialog and get the handle of the menu.

Thanx

[Michael Mattias]

What are you trying to do?

Seems like... you put up a popup window, and you want it to disappear as soon as the user does....... "something?" Tries to use any menu in any program? Presses a key or moves or clicks the mouse?

Than again, maybe instead of an event hook you should be doing a message hook on WM_INITMENU and WM_INITMENUPOPUP.


MCM

[Elias Montoya]

Hello Michael. What im trying to do? Im trying to disable globally any menu options named "properties". Its for the Internet cafe program i made. I dont want users to mess with properties of anything on the PC.

So far i can only get the window handle of the popup menu, but i can't get the menu handle. And seems like im not alone, according to this forum, a guy named Roger allen tried to do exactly what im trying to do.

So, basically what im trying to do is to translate hWnd to hMenu, because SetWinEventHook() reports only the hWnd but leaves out the hMenu.

[Elias Montoya]

Disregard, Seems like Peter hit the nail, But i thought it wasnt working because i mistyped the Declaration of MN_GETHMENU (as it wasnt in my Win32api.inc i looked for it in the web (0x01E1)).

Thanx.

[Dave Biggs]

What declaration did you end up using?

[Elias Montoya]

I used &h01E1

I will post the final code in the source code forum.

[Peter Jinks]

I used &h01E1

See post #3, 4th line of source code....

[Elias Montoya]

See post #3, 4th line of source code....

OHHH!!

Gotta pay more attention!

Heres the final work:

http://www.powerbasic.com/support/pbforums/showthread.php?p=306553#post306553