Re: Dynamically creating CDockablePanes

From:

"Nick Schultz" <nick.schultz@flir.com>

Newsgroups:

microsoft.public.vc.mfc

Date:

Fri, 2 May 2008 16:37:38 -0700

Message-ID:

<ODPYD2KrIHA.1200@TK2MSFTNGP03.phx.gbl>

It still doesn't look like I am destroying the CDockable Panel correctly. I
am getting some very wierd responses. I'll try to list all of the
occurances I'm noticing, perhaps somebody will see something:

1. When a CDockablePanel is docked and I hit the 'X' button, the window
disapears and memory and thread is cleared,which is the desired action,
however it looks like there is a base control still there, since the
ListCtrl in the mainframe will not resize to take up the whole frame. This
disapears when I resize, move, or create a new panel.

2. If the panel is in autohide mode and i close it, the panel disapears,
HOWEVER the tab bar stays with the tab for the panel, if I try to resize or
move , I get an access violation. I also get an access violation if I
hover the mouse over the tab.

3. If the panel is floating and I hit the 'X' button, the panel goes away,
however my OnPressCloseButton function does not get called, thus does not
free resources

4. When the panel is floating, I right click on the window and I get a menu
of ( Docking,X Floating,or Hide). If i select Hide, the OnPressCloseButton
function gets called and resources are freed

5. If the panel is floating, and I create another panel and dock it with
the floating panel, I can then hit the 'X' on one of the docked panels and
it will free resources AND removes the panel from the screen. This is the
desired result, however I want to be able to push the "X". (So it looks like
it has to be docked for the OnPressCloseButton to be called, when it floats
it uses a miniframe, so should is there a message that the miniframe would
post when it's "X" is pushed?)

6. If the panel is docked and I right click and select Hide, resources are
freed, however the panel stays and I get the same results as in [1]&[2].

Thanks you guys for the help,

Nick

"Nick Schultz" <NickSchultz@discussions.microsoft.com> wrote in message
news:8824E7C6-FA47-487A-9242-49A5028321E5@microsoft.com...

Alright, using PostMessage(WM_CLOSE) got rid of the access violation.
However the docked panel stays painted on the screen(i can also "paint"
other
windows in the area as well) until I resize the main window (when the
paint
method gets called) The main window only has one control and it is a
CListCtrl.

Thanks Ajay, it looks like I'm getting closer, however these functions
don't
get called at all when the CDockablePane is not docked. I am confirming
this
by setting breakpoints and watching the thread list in Process Explorer.

"Ajay Kalra" wrote:

On May 2, 5:03 pm, Nick Schultz
<NickSchu...@discussions.microsoft.com> wrote:

OK, I tried overriding both PostNcDestroy and OnPressCloseButton
functions
and it still isn't working the way I would like it to...

When I create the window, it starts out docked to the main frame. If I
undock the window and then close it, those functions do not get called.
If I
leave it docked, or undock it and dock it again and then close the
window,
those functions get called.

After going through those two functions, I then get an Access
violation:

Unhandled exception at 0x78a75e55 (mfc90ud.dll) in CanAnalyzer.exe:
0xC0000005: Access violation reading location 0xfeef000e.

and the break point is at the return statement:

LRESULT CWnd::Default()
{
        // call DefWindowProc with the last message
        _AFX_THREAD_STATE* pThreadState = _afxThreadState.GetData();
        return DefWindowProc(pThreadState->m_lastSentMsg.message,
                pThreadState->m_lastSentMsg.wParam,
pThreadState->m_lastSentMsg.lParam);

}

Here is the code of the closing functions:

void CGrapher::OnPressCloseButton()
{
        DestroyWindow(); }

void CGrapher::PostNcDestroy(){
        delete this;

}

So i guess I got a couple questions now, why am i getting that access
violation and why wont those functions get called when the
CDockablePane is
undocked(floating)?

Thanks for the help,

Nick

"Joseph M. Newcomer" wrote:

If you are allocating them on the heap, with new, the easiest way is
to add a
PostNcDestroy handler to your class whose body says
delete this;
replacing the TODO: line.

You cannot delete an object earlier than the PostNcDestroy handler.
joe

On Fri, 2 May 2008 10:59:01 -0700, Nick Schultz
<NickSchu...@discussions.microsoft.com>
wrote:

Hi there,

My user will need to be able to open any number of graphing
windows(CDockablePane) in my application. When the window is
closed, I want
the pane to be destroyed.

In order to do this I will have my window catch the press close
button event
(CPane::OnPressCloseButton) and then have it call DestroyWindow().

reading DestroyWindow description, it looks like it does everything
but it
does not destroy the CWnd object.

So how do I destroy the CWnd object? Do i just simply need to call
delete
(pointer to graph window). I was thinking I could override the
NotifyParent
function to catch child destroyed event and then deleting it then,
however
the parent gets notified BEFORE any destruction takes place.

I'm not sure if this is possible, but after calling DestroyWindow()
within
the OnPressCloseButton() function, could I just call "delete this"
to free
up any memory used by the graph window?

Any suggestions are greatly appreciated.

Nick

Joseph M. Newcomer [MVP]
email: newco...@flounder.com
Web:http://www.flounder.com
MVP Tips:http://www.flounder.com/mvp_tips.htm

Dont call DestroyWindow; use PostMessage(WM_CLOSE) instead. See if
that helps.

--
Ajay