C / C++ / MFC

_AnsHUMAN_ 21-May-09 22:39

_AnsHUMAN_

21-May-09 22:39

ON_WM_LBUTTONDOWN gets called when the user presses the left mouse button and not on the key press. I corrected my post after someone pointed out the mistake and suggested you to use the WM_KEYDOWN message instead. You can perform a check for VK_DOWN & VK_RETURN.
You can add the WM_KEYDOWN event in the same manner you do for WM_LBUTTONDOWN

You need to google first, if you have "It's urgent please" mentioned in your question.
Wink | ;-)

_AnShUmAn_

susanne121-May-09 22:53

21-May-09 22:53

i did it in this way but it did not work when i press any or the Return Key.

BEGIN_MESSAGE_MAP(CTest_View, CEditView)
ON_WM_KEYDOWN(WM_KEYDOWN,OnKeyDown)
END_MESSAGE_MAP()

void CTest_View::OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags)
{

}

ThatsAlok21-May-09 23:10

ThatsAlok

21-May-09 23:10

Please check PreTranslateMessage!

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susanne121-May-09 23:20

Re: WM_KEYDOWN [modified]

21-May-09 23:20

i ckecked the PreTranslateMessage(MSG *pMsg), so i tried to override it but the debugger does come to it when i pressed any key.

BOOL CTest_View::PreTranslateMessage(MSG *pMsg)
{
// Do stuff
return true;
}

_AnsHUMAN_ 21-May-09 23:17

_AnsHUMAN_

21-May-09 23:17

are you adding your event handlers manually?
why not use the wizard for the same because ON_WM_KEYDOWN() is what you need to add to the message map.
The VS editor adds void Cyourclassview::OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags)
which later on gets called by the framework from where you can call your function to execute

You need to google first, if you have "It's urgent please" mentioned in your question.
Wink | ;-)

_AnShUmAn_

modified on Friday, May 22, 2009 5:27 AM

Stuart Dootson21-May-09 23:23

21-May-09 23:23

You don't need the parameters you've passed to ON_WM_KEYDOWN - the line shown below is sufficient:

ON_WM_KEYDOWN()

I added a keydown handler to a sample SDI app's view and it captured key-presses fine, including the Return key.

Oh - one other thing - you should call the default CView key-down handler for any messages you don't handle. My WM_KEYDOWN handler (with no functionality) looks like this:

void CsditryView::OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags)
{
   // TODO: Add your message handler code here and/or call default

   CView::OnKeyDown(nChar, nRepCnt, nFlags);
}

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

susanne121-May-09 23:39

21-May-09 23:39

in the CTest_View.cpp i wrote this:

BEGIN_MESSAGE_MAP(CTest_View, CEditView)// CTest_View Class is derived from CEditView Class
ON_WM_KEYDOWN()
END_MESSAGE_MAP()
/
/
/
void CTest_View::OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags)
{
if (nChar == VK_RETURN)
{

}
CEditView::OnKeyDown(nChar, nRepCnt, nFlags);
}

But it stiil not work???

Stuart Dootson21-May-09 23:52

21-May-09 23:52

Looking at one of your other messages where you show your PreTranslateMessage override - you return TRUE from your PreTranslateMessage override and if do that, you're telling MFC that you've done something with the message and it shouldn't be passed on to your window's message handlers. Try altering the return from PreTranslateMessage to FALSE...

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

susanne122-May-09 0:06

22-May-09 0:06

i change it but nothing work.

BEGIN_MESSAGE_MAP(CProSeS_SQLTalk_View, CEditView)
ON_WM_KEYDOWN()
END_MESSAGE_MAP()

void CTestView::OnKeyDown(UINT nChar, UINT nRepCnt, UINT nFlags)
{
if (nChar == VK_RETURN)
{

}
CEditView::OnKeyDown(nChar, nRepCnt, nFlags);
}
///////////////////////////////////////////////////////////////////////////////////////////
BOOL CTest_View::PreTranslateMessage(MSG *pMsg)
{
if(pMsg->message == WM_KEYDOWN)
{
if(pMsg->wParam == VK_RETURN)
{
//int bIsShiftKeyDown=(int)::GetAsyncKeyState(int nvKey);
}
}
return FALSE;
}

Stuart Dootson22-May-09 0:26

22-May-09 0:26

So...do breakpoints placed in your view's PreTranslateMessage get triggered?

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

susanne122-May-09 0:31

22-May-09 0:31

i already put breakpoints as you said but the Debugger did not go to the PreTranslateMessage().

Rajesh R Subramanian22-May-09 0:46

Rajesh R Subramanian

22-May-09 0:46

And you're sure that you are building a debug build?

It is a crappy thing, but it's life -^ Carlo Pallini

Stuart Dootson22-May-09 0:58

22-May-09 0:58

Are you sure your view class is being used?

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

susanne122-May-09 1:02

22-May-09 1:02

yes.

susanne122-May-09 1:03

22-May-09 1:03

i do not know, how can i check that ? and if it is not being used what should i do?

Stuart Dootson22-May-09 1:12

22-May-09 1:12

Have you got some code in your CMainFrame class that you can a) add some code to, and b) guarantee will be executed application's running?

If so, then add a call to the active view's OnKeyDown handler:

GetActiveView()->OnKeyDown((UINT)'a', 1, 0);

Set a breakpoint on that line. When the breakpoint triggers, repeatedly step into the call (it'll call the GetActiveView() methods first, then step back out, then step into the OnKeyDown handler). When you get to an OnKeyDown handler, you can see what the view type is.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

susanne122-May-09 1:26

22-May-09 1:26

i got this error when i wrote this in my CMainFrame class:

GetActiveView()->OnKeyDown((UINT)'a', 1, 0);

error C2248: "CWnd::OnKeyDown" Members of a derived class cannot access private members of a base class.

Stuart Dootson22-May-09 2:09

22-May-09 2:09

My fault - didn't realise OnKeyDown was private. Ummm, OK - you need to add (to your view class) an override for a public method of CView. Call that from your CMainFrame. For example, CDocument:

CDocument* CTest_View::GetDocument() const
{
   return CEditView::GetDocument();
}

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

susanne122-May-09 2:28

22-May-09 2:28

i have this code in my Doc.cpp

CTestDoc* CTest_View::GetDocument() const
{
ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CTest_Doc)));
return (CTest_Doc*)m_pDocument;
}
it cause a trouble when i add this :

CDocument* CTest_View::GetDocument() const
{
return CEditView::GetDocument();
}

my SDI Application is splitted horizontally to two parts adn i need to get if the Return Key in the upper part being pressed.

Stuart Dootson22-May-09 4:45

22-May-09 4:45

susanne1 wrote:
my SDI Application is splitted horizontally to two parts adn i need to get if the Return Key in the upper part being pressed.

There's the salient point - you've got a splitter view between MFC and the view that you want to receive messages.

Where is your splitter created? In the CMainFrame?

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

susanne124-May-09 22:28

24-May-09 22:28

Yes.

Stuart Dootson25-May-09 0:46

25-May-09 0:46

Right, well I think the splitter window's trapping your return key presses - looking at the splitter window's OnKeyDown handler, it has a case for VK_RETURN.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

susanne125-May-09 2:06