asked on

* If you want a challenge, here it is * Command routing nightmare

Ah hello.

I have a serious issue that is causing major problems.

I have a command handler for a range of IDs on a menu:

ON_COMMAND_RANGE(ID_VIEW_FILTER, MAX_COMMAND_RANGE, OnViewFilterByPack)

with

#define MAX_COMMAND_RANGE ID_VIEW_FILTER + 31 + NUMBER_OF_ADDITIONAL_ITEMS
#define NUMBER_OF_ADDITIONAL_ITEMS 4

#define ID_VIEW_FILTER                              30000

I have a tree control on my app. Whenever I complete a drag drop operation on the tree (drag to correct place and release left mouse button), I get a message generated from somewhere that calls OnViewFilterByPack. This message has ID 30035; obviously falling into the range for this handler. Now, if I change the value of ID_VIEW_FILTER to 40000, this message has ID 40035. This in itself might be a clue.

My call stack is (easier to read in Notepad with word wrap off)

>      MyApp.exe!CMyView::OnViewFilterByPack(unsigned int nID=30035) Line 2025      C++
     mfc71d.dll!_AfxDispatchCmdMsg(CCmdTarget * pTarget=0x00c5b1a8, unsigned int nID=30035, int nCode=0, void (void)* pfn=0x0043f8d4, void * pExtra=0x00000000, unsigned int nSig=55, AFX_CMDHANDLERINFO * pHandlerInfo=0x00000000) Line 103      C++
     mfc71d.dll!CCmdTarget::OnCmdMsg(unsigned int nID=30035, int nCode=0, void * pExtra=0x00000000, AFX_CMDHANDLERINFO * pHandlerInfo=0x00000000) Line 396 + 0x27      C++
     mfc71d.dll!CView::OnCmdMsg(unsigned int nID=30035, int nCode=0, void * pExtra=0x00000000, AFX_CMDHANDLERINFO * pHandlerInfo=0x00000000) Line 160 + 0x18      C++
     MyApp.exe!CMyView::OnCmdMsg(unsigned int nID=30035, int nCode=0, void * pNewData=0x00000000, AFX_CMDHANDLERINFO * pHandlerInfo=0x00000000) Line 1151      C++
     mfc71d.dll!CWnd::OnCommand(unsigned int wParam=30035, long lParam=0) Line 2550      C++
     mfc71d.dll!CWnd::OnWndMsg(unsigned int message=273, unsigned int wParam=30035, long lParam=0, long * pResult=0x0012fcf0) Line 1759 + 0x1c      C++
     mfc71d.dll!CWnd::WindowProc(unsigned int message=273, unsigned int wParam=30035, long lParam=0) Line 1745 + 0x1e      C++
     mfc71d.dll!AfxCallWndProc(CWnd * pWnd=0x00c5b1a8, HWND__ * hWnd=0x006c0c0e, unsigned int nMsg=273, unsigned int wParam=30035, long lParam=0) Line 241 + 0x1a      C++
     mfc71d.dll!AfxWndProc(HWND__ * hWnd=0x006c0c0e, unsigned int nMsg=273, unsigned int wParam=30035, long lParam=0) Line 389      C++
     mfc71d.dll!AfxWndProcBase(HWND__ * hWnd=0x006c0c0e, unsigned int nMsg=273, unsigned int wParam=30035, long lParam=0) Line 209 + 0x15      C++
     USER32.DLL!77e3a420()
     USER32.DLL!77e14605()
     mfc71d.dll!CWnd::AttachControlSite(CHandleMap * pMap=0x00c58008) Line 445 + 0x16      C++
     mfc71d.dll!CWnd::FromHandle(HWND__ * hWnd=0x002f0d36) Line 311      C++
     mfc71d.dll!CWnd::GetTopLevelParent() Line 2623      C++
     00007553()
     USER32.DLL!77e15b77()
     mfc71d.dll!AfxInternalPumpMessage() Line 188      C++
     mfc71d.dll!CWinThread::PumpMessage() Line 916      C++
     mfc71d.dll!CWinThread::Run() Line 637 + 0xb      C++
     mfc71d.dll!CWinApp::Run() Line 701      C++
     mfc71d.dll!AfxWinMain(HINSTANCE__ * hInstance=0x00400000, HINSTANCE__ * hPrevInstance=0x00000000, char * lpCmdLine=0x00142db5, int nCmdShow=1) Line 49 + 0xb      C++
     MyApp.exe!WinMain(HINSTANCE__ * hInstance=0x00400000, HINSTANCE__ * hPrevInstance=0x00000000, char * lpCmdLine=0x00142db5, int nCmdShow=1) Line 25      C++
     MyApp.exe!WinMainCRTStartup() Line 390 + 0x39      C
     KERNEL32.DLL!7c59893d()
     mfc71d.dll!CRichEditView::OnKeyDown(unsigned int nChar=, unsigned int nRepCnt=, unsigned int nFlags=) Line 1030 + 0x8      C++

I cannot see at all where this message is coming from, and am pretty desperate to sort this out ASAP. The confusing thing is it is generated by the drag drop-LButton up operation.

Does anyone have any ideas on this ?

TIA

mrwad99

ASKER

More fiddling has revealed the following:

with ID ID_VIEW_FILTER as 30001 instead of 30000, OnViewFilterByPack gets called but with a parameter of 30036

If I change

#define NUMBER_OF_ADDITIONAL_ITEMS 4

to

#define NUMBER_OF_ADDITIONAL_ITEMS 3

I have no problems.

So what ****is**** the problem ?

AlexFM

Override OnCommand function in the window which receives this message, and get additional information about message source there. See CWnd::OnCommand MSDN topic for details.
BTW, last line of your call stack looks strange:

MyApp.exe!WinMainCRTStartup() Line 390 + 0x39 C
KERNEL32.DLL!7c59893d()
mfc71d.dll!CRichEditView::OnKeyDown(unsigned int nChar=, unsigned int nRepCnt=, unsigned int nFlags=) Line 1030 + 0x8 C++

What does CRichEditView::OnKeyDown do here?? Possibly you have some idea knowng your application context.

AndyAinscow

Clarify please.
Are you saying
#define NUMBER_OF_ADDITIONAL_ITEMS 4
will result in the COMMAND message but
#define NUMBER_OF_ADDITIONAL_ITEMS 3
does not?

AndyAinscow

Is the define MAX_COMMAND_RANGE used anywhere else apart from for this ON_COMMAND_RANGE message map entry?

ASKER CERTIFIED SOLUTION

AndyAinscow

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

mrwad99

ASKER

Thanks for the reply AlexFM.

>> What does CRichEditView::OnKeyDown do here?? Possibly you have some idea knowng your application context.

I dont have a rich edit view in my application. The application is an MDI app with a splitter pane split into three. Two of the views are treeviews, one is a fileview. Essentially Windows Explorer with an additional treeview on the left hand side.

From MSDN:

"The low-order word of wParam identifies the command ID of the menu item, control, or accelerator. The high-order word of wParam specifies the notification message if the message is from a control. If the message is from an accelerator, the high-order word is 1. If the message is from a menu, the high-order word is 0."

Right. I breakpoint on OnCommand in the view that handles this message (view that contains OnViewFilterByPack) and when

LOWORD(wParam) == 30036 (the message getting passed to OnViewFilterByPack)
HIWORD(wParam) = 0, so the message is from a menu
lParam is 0, so it is not a control that sent the message.

But how on earth is the menu sending the message ? I have not clicked it !

AndyAinscow

Does it happen in release build?

mrwad99

ASKER

Hi Andy

Yes, it does happen in release build.

<Trying to sort this by gradually changing old code to have the new changes. Make changes, it breaks. Undo exact same changes, it still breaks. Nice.>

ARGHHHHHHHHHHHHH...........................

AndyAinscow

And my first three comments?

AlexFM

Can you find ID_VIEW_FILTER value which doesn't produce his effect?

mrwad99

ASKER

Dammit.

I had just typed a big response there when I decided to double check on where I was using ID_VIEW_FILTER in my code.

And guess what.

I have a diagnostic function, called from within OnLButtonUp, that does something wonderful. Yes, it does a

::PostMessage(this->m_hWnd, WM_COMMAND, ID_VIEW_FILTER + 35,0);

which should have been commented out long ago.

This explains what I am seeing.

<blushes bigstyle>

So, I have just wasted some of your time (sorry) and a lot of my time. And even had a bit of a haircut for free (well, decreased the need for a haircut, if you get me).

Oh well.

But this has raised interesting issues.

1) mfc71d.dll!CRichEditView::OnKeyDown.....

why on earth was that being called when I don't have a CRichEditView in my app ?

2) Is there any way I could have determined from the call stack, or any other way, that OnViewFilterByPack was being called as a result of a PostMessage (grrrrr!) *from within one of my diagnostic functions ?* 'Cause if there was, and I would have known about it, this whole issue would not have come about.

Sorry again for being dumb :)

SOLUTION

AlexFM

membership

This solution is only available to members.

To access this solution, you must be a member of Experts Exchange.

Start Free Trial

AndyAinscow

No problems.

1) ? - no idea
2) Not that I know of, especially as the call stack 'thought' it was coming from a richedit view

mrwad99

ASKER

Right, thanks for that. Andy's comment was the closest to an answer as that indirectly hinted at me searching for ID_VIEW_FILTER which gave the answer.

Thanks again :)

AndyAinscow

I agree with Alex re "Search in Files", hence my first set of three comments.

I have a rule which is roughly - Don't assume this is the problem, check first. (Many years ago I spent ages attempting to improve the peformance of some code, nothing I did helped. Eventually I found >90% of the time it used was in one API call, so I quickly rewrote part of the app so as to not depend on that call - it then took about 20% of the original time. I wished I had checked first)

*** If you want a challenge, here it is *** Command routing nightmare

* If you want a challenge, here it is * Command routing nightmare