C / C++ / MFC

3-Sep-02 0:52

Howdy!

I've managed to build a status bar and I can assign it a
value when the application starts, but how can I update it while
the application is running?

In the CMainFrame::OnCreate I can use
m_wndStatusBar.GetStatusBarCtrl() to get the address of
the StatusBarCtrl, but how could I get it outside CMainFrame class?

-Marko H. Confused | :confused:

Tomasz Sowinski3-Sep-02 1:00

3-Sep-02 1:00

If you want to set the text in leftmost part of status bar, use CFrameWnd::SetMessageText. For other statusbar panes, use normal ON_UPDATE_CMD_UI mechanism.

Tomasz Sowinski -- http://www.shooltz.com

** Putt knot yore thrust inn spel chequers. **

Anonymous3-Sep-02 2:27

3-Sep-02 2:27

uh-oh... I'm a newbie.

What I meant is that from a CDocument class function I
want to change the status bar first pane text.

How can I write status bar from there?
I don't have inside CDOcument class the address of the CFrameWnd
class object to use CFrameWnd::SetMessageText.

Tomasz Sowinski3-Sep-02 2:45

3-Sep-02 2:45

Use this:

static_cast<CFrameWnd *>(AfxGetMainWnd())->SetMessageText("I'm on status bar now");

Keep in mind that this changes the status bar text until next idle update UI cycle is executed. Do you want to change this text permantently?

Tomasz Sowinski -- http://www.shooltz.com

** Putt knot yore thrust inn spel chequers. **

3-Sep-02 3:10

Still baffled...

I added the code, no effect.

I want to show on the status bar when the data was last time
saved successfully. Now it just shows the date & time once,
when CFrameWnd is created. CDocument object function
should be able to update the information permanently.

Tomasz Sowinski3-Sep-02 3:16

3-Sep-02 3:16

Anonymous wrote:
I want to show on the status bar when the data was last time
saved successfully

Instead of standard 'Ready' message, right? If this is the case, override CFrameWnd::GetMessageString:

void CMainFrame::GetMessageString(UINT nID, CString & rMessage) const
{
if (AFX_IDS_IDLEMESSAGE == nID)
{
rMessage = "I'm on status bar";
return;
}

CMDIFrameWnd::GetMessageString(nID, rMessage);
}

Tomasz Sowinski -- http://www.shooltz.com

** Putt knot yore thrust inn spel chequers. **

lucy3-Sep-02 3:49

lucy

3-Sep-02 3:49

have a look at this article http://www.codeproject.com/script/Submit/ViewHTML.asp?guid=%2Fuseritems%2Fstatusbar%2Easp%2D2%2F20%2F2002

HTH.

Broken link?

Anonymous3-Sep-02 22:38

3-Sep-02 22:38

The link is a dead end...? Or is it just my Netscape Navigator 4.75?

MarkDoubson4-Sep-02 2:37

MarkDoubson

4-Sep-02 2:37

Use ((CFrameWnd*) AfxGetMainWnd())->SetMessageText("...");

RalfPeter3-Sep-02 4:14

RalfPeter

3-Sep-02 4:14

I take that you're able to create a status bar in MainFrame (including setting pane # and size). Once outside of MainFrame, youneed to get a pointer to it to modify the status bar remotely.

#include "MainFrm.h"//or equivalent .h
.
.
.
CMainFrame* pFrame = (CMainFrame*)AfxGetApp()->m_pMainWnd;//pointer to mainframe object
.
.
.
pFrame->UpdateStatus(1, "1st panel message...");//and so on

ralf.riedel@usm.edu

SOLVED!!

Anonymous3-Sep-02 22:32

3-Sep-02 22:32

Aaaahh... I'm a moron (but not moron enough not to write under anonymous Wink | ;-)

1st: status bar has this default feature to show "ready" or tooltip on it. I forgot that.
I had made my own simple status bar, and I mixed on the way SetMessageText
and SetPaneText.

2nd: I couldn't get my hands on the CMainFrame object. Thanks to the
replies, now I could!

3rd: (back to the being stupid) When I was instructed to use pFrame->UpdateStatus(1, "1st panel message...")
I was just baffled ".. but there is no UpdateStatus in CFrameWnd class..." Smile | :)

Ok, here is how it works now, in case this helps someone else. I am NOT
updating the default message text on the status bar, I have created my own
pane with a text:

in MainFrm.h must be lines
public:
void UpdateStatusBar(CString sMessage = "");

- - - - - -

int CMainFrame::OnCreate(LPCREATESTRUCT lpCreateStruct)
{
if (CFrameWnd::OnCreate(lpCreateStruct) == -1)
return -1;

if (!m_wndStatusBar.Create(this) ||
!m_wndStatusBar.SetIndicators(indicators,
sizeof(indicators)/sizeof(UINT)))
{
TRACE0("Failed to create status bar\n");
return -1; // fail to create
}

UpdateStatusBar();

return 0;
}

- - - - - -

void CMainFrame::UpdateStatusBar(CString sMessage)
{
CWinApp* pApp = AfxGetApp();

// the values are read from the registry
CString strValue, strValue2;
strValue = pApp->GetProfileString("Latest update","Date");
strValue2 = pApp->GetProfileString("Latest update","State");

if (strValue.IsEmpty()) {
m_sPaneText = "Data saved: n/a"; }
else {
m_sPaneText.Format("Data saved: %s, %s", strValue, strValue2); }

CStatusBarCtrl &stCtrl = m_wndStatusBar.GetStatusBarCtrl();

// Let's keep it simple...
stCtrl.SetSimple();

// in case you want send a different message to the status bar
// m_sPaneText is a member of CMainFrame
if (sMessage.IsEmpty())
stCtrl.SetText(m_sPaneText,255,0);
else
stCtrl.SetText(sMessage,255,0);

}

- - - - - -
...and then at the same in another class...

In AppDoc.cpp must be line
#include "MainFrm.h"

- - - - - -

void CAppDoc::SaveDataToServer()
{
// blah blah blah... save data and other dull jobs...
// in my case write to registry. The values are read in
// UpdateStatusBar later on and displayed.

// update the status bar from CDocument class object
CMainFrame* pFrame = (CMainFrame*)AfxGetApp()->m_pMainWnd;//pointer to mainframe object
pFrame->UpdateStatusBar();

return;
}

- - - - - -

VTables

pankajdaga3-Sep-02 0:48

pankajdaga

3-Sep-02 0:48

Hi again everyone,

Does anyone know of a good web resource or a book where I can find information regarding vtables and how to manipulate them with C++.

Thanks,

Pankaj

Tomasz Sowinski3-Sep-02 0:53

3-Sep-02 0:53

pankajdaga wrote:
where I can find information regarding vtables and how to manipulate them with C++.

What do you mean by 'manipulating vtables'?

Tomasz Sowinski -- http://www.shooltz.com

** Putt knot yore thrust inn spel chequers. **

pankajdaga3-Sep-02 1:35

pankajdaga

3-Sep-02 1:35

I was just wondering if it is possible to directly access the contents of a vtable.

Pankaj

Without struggle, there is no progress

Tomasz Sowinski3-Sep-02 2:11

3-Sep-02 2:11

pankajdaga wrote:
if it is possible to directly access the contents of a vtable

It isn't possible in portable manner. Why do you want to do this?

Tomasz Sowinski -- http://www.shooltz.com

** Putt knot yore thrust inn spel chequers. **

pankajdaga3-Sep-02 3:20

pankajdaga

3-Sep-02 3:20

Just for educational reasons. I am a student at a university. Just wanted to know if it was possible to access the vtable pointer from the C++ code.

Pankaj

Without struggle, there is no progress

Hostalet Wandosell3-Sep-02 0:59

Hostalet Wandosell

3-Sep-02 0:59

The main topic is not vtables, but there is very nice code, i like this link
http://www.codeproject.com/atl/atl_underthehood_.asp

regards

-----
Mit freundlichen Grüssen/Best Regards/Un cordial saludo.

Ing. José Manuel Hostalet Wandosell, Fraunhofer IPA, Abt.323/Robotersysteme
Nobelstrasse 12, D-70569 Stuttgart (Germany)
mailto:jose.hostalet@ipa.fhg.de, http://www.ipa.fhg.de

Jeremy Pullicino3-Sep-02 2:06

Jeremy Pullicino

3-Sep-02 2:06

pankajdaga wrote:
vtables and how to manipulate them with C++.

You are one courageous programmer!

Jeremy Pullicino
Professional C++ Developer

Done any hacking lately?

Joaquín M López Muñoz3-Sep-02 2:59

Joaquín M López Muñoz

3-Sep-02 2:59

Take a look at Jan Gray's article C++: Under the Hood[^] (warning, hardcore stuff).

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo