C / C++ / MFC

4-Mar-09 23:25

Hi all,

i Have SDI type application,I m creating a Mutex to avoid multiple instance of application. and use system tray icon feature.

for creating mutex i m using this code:

HANDLE hMutex = ::CreateMutex(NULL, TRUE, _T("GlobalMainMutex"));

switch(::GetLastError())
{
    case ERROR_SUCCESS:
      // Mutex created successfully. There is no instance running
      break;

    case ERROR_ALREADY_EXISTS:

      // Mutex already exists so there is a running instance of our app.
    return FALSE;

    default:
      // Failed to create mutex by unknown reason
     return FALSE;
  }

for system tray icon i m taking help of this article.

http://www.codeproject.com/KB/shell/systemtray.aspx[^]

My problem is that is application is already running and its in hide mode and icon present in system tray,now when i click on my exe than its not open becoz of mutex.

i what when application is already running or its hide than if i click on exe icon than the hide application can show.

please tell me how can i do this.

thanks in advance.

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

Code-o-mat4-Mar-09 23:59

4-Mar-09 23:59

First of all, if i were you i'd use a different name for the mutex because "GlobalMainMutex" doesn't seem to be that unique as it should, maybe use a GUID generator and use the generated code as name, or as part of the name of your mutex.
To show the already running instance you could either broadcast a registered message when your new instance detects another instance running upon which your program brings up its window, this sounds a tiny bit overkill (post/send a message to EVERY running app in the system) but it is easy to do, or you could try to find your own process by enumerating processes and checking their names or executable names or whatever and posting a thread message to it, or you could enumerate windows on the system and if you find the one belonging to your process (for example by class name) post a message to it.

p.s: to avoid confusement, i don't mean use a GUID generator to generate a new name every time your app starts, since that would -of course- make the whole idea useless...

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

Le@rner5-Mar-09 0:14

5-Mar-09 0:14

please can u explain me with any example. i m very thankful to u.

thanks.

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

Code-o-mat5-Mar-09 0:34

5-Mar-09 0:34

Well, i currently have no time to write you a complete example proggie but i can try to give you a "skeleton", i hope it will help you somewhat

UINT WM_ACTIVATE_MY_APPLICATION = RegisterWindowMessage("WM_ACTIVATE_MY_APPLICATION_315FrYu76A");
...
if (there_is_another_instrance_running)
{
  BroadcastSystemMessage(BSF_POSTMESSAGE, BSM_APPLICATIONS, WM_ACTIVATE_MY_APPLICATION, 0, 0);
  exit(0);
}
...
BEGIN_MESSAGE_MAP(CMyVeryOwnApp, CWinApp)
  ...
  ON_THREAD_MESSAGE(WM_ACTIVATE_MY_APPLICATION, OnActivateMyVeryOwnApp)
  ...
END_MESSAGE_MAP()
...
LRESULT CMyVeryOwnApp::OnActivateMyVeryOwnApp(WPARAM wParam, LPARAM lParam)
{
  ...
  ShowMyVeryOwnMainWindowAndBringToFront();
  ...
}

I hope this helps somewhat...

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

Le@rner5-Mar-09 1:13

5-Mar-09 1:13

this error comes

error C2440: 'static_cast' : cannot convert from 'LRESULT (__thiscall CDataDoctorsEmployeePlannerApp::* )(WPARAM,LPARAM)' to 'void (__thiscall CWinThread::* )(WPARAM,LPARAM)'

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

Code-o-mat5-Mar-09 1:22

5-Mar-09 1:22

And you really have no idea what this could mean? Change the LRESULT to void in the method's declaration and definition.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

Le@rner7-Aug-09 18:17

7-Aug-09 18:17

Code-o-mat wrote:
ShowMyVeryOwnMainWindowAndBringToFront();

What is in this function.

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

Code-o-mat7-Aug-09 21:29

7-Aug-09 21:29

Code to make your window visible using ShowWindow[^], bring it to front using BringWindowToTop[^], and whatever else you like...

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

Le@rner7-Aug-09 21:49

7-Aug-09 21:49

Its need handle of window.

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

Code-o-mat7-Aug-09 21:59

7-Aug-09 21:59

I don't see why you need that but it is called m_hWnd, a member of CWnd which is among the superclasses of your main window.

> The problem with computers is that they do what you tell them to do and not what you want them to do. <
> Life: great graphics, but the gameplay sux. <

Le@rner7-Aug-09 23:04

Problem sending SMS using EDGE modem

7-Aug-09 23:04

Thanks

To accomplish great things, we must not only act, but also dream;
not only plan, but also believe.

efarook4-Mar-09 22:59

efarook

4-Mar-09 22:59

Hello,

I have an application that sends SMS to several clients, one by one. I am using EDGE modem and AT commands for this purpose.

My problem is that the application sometimes (not always) fails to send few SMSs (some of my clients complain that they didn't get any SMS). Can anyone tell me why this happens? Or, how can I read the SMS sent-status?

Thanks

How to override OnOK() and OnESC() in an instance of CDialog?

B_U_A4-Mar-09 22:43

B_U_A

4-Mar-09 22:43

Using VC6++, I created a little dialog based test application with the app wizard.
I have a tab control which shows several tabs. Swapping between the individual tabs works fine.
The content of the tabs consists of dialogs which I have derived from CDialog - hence they have an ESC /CANCEL and OK/ENTER message handler attached.

My problem is that when the focus sits on any of the tabs (i.e. I can see the chid dialog that the tab displays, then when hitting ESC or ENTER, this content of the child window disappears, because obviously the CDialog OnOK() and OnESC() member functions get called.

My beginners knowledge doesn't allow me to dive a bit deeper into the code to override the corresponding member functions (which I think are onOK() ...etc. is that correct?

Could someone explain (and ideally post some lines of code for a beginner), what needs to be done?

Many thanks.

Re: How to override OnOK() and OnESC() in an instance of CDialog?

Cedric Moonen4-Mar-09 22:47

Cedric Moonen

4-Mar-09 22:47

See the FAQ[^]

Cédric Moonen
Software developer

Charting control [v1.5]
OpenGL game tutorial in C++

Re: How to override OnOK() and OnESC() in an instance of CDialog?

B_U_A4-Mar-09 23:24

B_U_A

4-Mar-09 23:24

Dear Cédric,
Many thanks for your prompt and efficient help.
As you can see I am new to all this, but now that I know about the FAQ section, I will check that first.
Many thanks again. Problem solved.

Re: How to override OnOK() and OnESC() in an instance of CDialog?

Hamid_RT4-Mar-09 23:55

Hamid_RT

4-Mar-09 23:55

Its good site for you,you can find new things about MFC/C++.http://www.functionx.com/[^]

Of one Essence is the human race
thus has Creation put the base
One Limb impacted is sufficient
For all Others to feel the Mace
(Saadi )

How to receive buffer from a directx based game

kallol kumar4-Mar-09 20:56

kallol kumar

4-Mar-09 20:56

Hello

Suppose a directx based game(like nfs) is running. I want to grab the buffer which is shown in desktop(all frame). Actually the scenerio is like that: Game's Front buffer will capture by my application then modify this buffer(like my own text will add) and finally display my own buffer data as a game.

Does anybody have some ideas how to do this? If any ideas please let me know.

Regards
Kallol Kumar

Re: How to receive buffer from a directx based game [modified]

Code-o-mat4-Mar-09 21:59