C / C++ / MFC

Re: List Box &amp; Rich Edit box

18-Feb-07 22:52

Loop though for reading for a fixed length, as you are doing now, and keep appending that array in a std::string variable.

Prasad
Notifier using ATL | Operator new[],delete[][^]

David Crow16-Feb-07 2:52

David Crow

16-Feb-07 2:52

Suresh H wrote:
case WM_COMMAND:
switch(LOWORD(wParam))
{
case LBN_DBLCLK:
{
HWND hwndListBox = GetDlgItem(hwnd, IDC_SLIST);
int iCurSel =::SendMessage(hwndListBox,LB_GETCURSEL,0,0);
TCHAR FName[25];
SendMessage(hwndListBox,LB_GETTEXT,(WPARAM)iCurSel,(LPARAM)FName);

This is Win32 code. Since you have an MFC application, based on the presence of CStdioFile, take advantage of it. Use ClassWizard to create a LBN_DBLCLK handler. In that handler, call the listbox's GetCurSel() method to get the index of the currently selected item. Then call the edit control's SetWindowText() method, or its StreamIn() method, to display the text (after opening the file and reading its contents, of course).

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Windows Menus and the WM_MENUCOMMAND message

Martin081515-Feb-07 22:41

15-Feb-07 22:41

Hello,

I'm working with/on an application with a resource based menu. This application is more or less driven by the programming (script) language tcl and has a lot of APIs introducing C++ functionality to tcl.

Now I built an API to manage (popup) menus and their menu items, to create new items with tcl script callbacks, etc.

The main point in my "construct" is to use a template menu item from a template menu resource.
I created a menu in the resources as template containing a menu item as template.

Everything was fine until I realized, that I seemed to have no chance to differentiate between the new commands having all the same id, but different application defined data - changed via the MENUITEMINFO and the related functions Get/SetMenuItemInfo.

I changed the menus after their creation to send a WM_MENUCOMMAND message instead of a WM_COMMAND message by setting the dwStyle flag MNS_NOTIFYBYPOS inside the MENUINFO structure via a call to SetMenuInfo.

Now - finally to the problem and the question - why I never receive the WM_MENUCOMMAND message?

I patched CMainFrame::PreTranslateMessage method to catch the WM_MENUCOMMAND message, I tried with CMainFrame::WindowProc, and by registering a ON_MESSAGE handler inside the message map, but ... nothing worked!

Thanks for any reaction in advance!

Best regards,

Martin Lemburg

prasad_som16-Feb-07 1:51

16-Feb-07 1:51

Can you provide code ? how you are creating menu, using SetMenuInfo etc. ?

Prasad
Notifier using ATL | Operator new[],delete[][^]

Martin081516-Feb-07 2:22

16-Feb-07 2:22

Yes - here's some "reduced" code:

1. the creation of a popup menu:

DWORD       style       = 0;
CMenu       *popup      = (CMenu *) NULL;
MENUINFO    menuInfo;   // see below (1)

memset( &menuInfo, 0x0, sizeof( MENUINFO ) );   // (1)

// create the new menu object
//
popup   = new CMenu();

// create the new popup menu
//
if ( ( popup != NULL ) && ( popup->CreatePopupMenu() == TRUE ) )
{
    // initialize the menu info structure to get its dwStyle member
    //
    menuInfo.cbSize = sizeof( MENUINFO );
    menuInfo.fMask  = MIM_STYLE;

    if ( popup->GetMenuInfo( &menuInfo ) == TRUE )
    {
        style   = menuInfo.dwStyle;

        // (re)initialize the menu info structure to change only its dwStyle member
        //
        memset( &menuInfo, 0x0, sizeof( MENUINFO ) );

        menuInfo.cbSize     = sizeof( MENUINFO );
        menuInfo.fMask      = MIM_APPLYTOSUBMENUS | MIM_STYLE;
        menuInfo.dwStyle    = style | MNS_NOTIFYBYPOS;

        if ( popup->SetMenuInfo( &menuInfo ) == TRUE )
        {
            tcl_publishResult( ip, (char *) create_popup_token( popup ) );
            return TCL_OK;
        }
    }
}

system_error_message( ip, "couldn't create popup menu" );

if ( popup != NULL )
{
    delete popup;
}

return TCL_ERROR;

2. the insertion of a created popup menu:

int             itemPosition    = 0;
char            *label          = (char *) NULL;
CWnd            *root           = (CWnd *) NULL;
CMenu           *menu           = (CMenu *) NULL,
                *popup          = (CMenu *) NULL;
MENUITEMINFO    menuInfo;       // see below (1)

Menu_if_tcl_MenuItem_s_t    *menuItem   = (Menu_if_tcl_MenuItem_s_t *) NULL;

memset( &menuInfo, 0x0, sizeof( MENUITEMINFO ) );   // (1)

menuInfo.cbSize = sizeof( MENUITEMINFO );

// get the popup menu pointer and the label ...
//
// ...
//

// access the main window
//
root    = AfxGetApp()->m_pMainWnd;
menu    = get_owning_menu( ip, root->GetMenu(), positionsList, itemPosition );

if ( ( menu != NULL ) &&
     ( itemPosition != -1 ) &&
     ( (UINT) itemPosition <= menu->GetMenuItemCount() ) )
{
    if ( menu->InsertMenu( itemPosition, MF_BYPOSITION | MF_STRING | MF_POPUP, (UINT) popup->m_hMenu, label ) == TRUE )
    {
        menuItem    = create_menu_item( PopupMenuItem, "" );

        menuInfo.fMask      = MIIM_DATA | MIIM_STATE;
        menuInfo.fState     = MFS_ENABLED;
        menuInfo.dwItemData = (ULONG_PTR) menuItem;

        if ( menu->SetMenuItemInfo( itemPosition, &menuInfo, TRUE ) == TRUE )
        {
            root->DrawMenuBar();
            tcl_publishResult( ip, menuItem->token );
            return TCL_OK;
        }
    }
}

system_error_message( ip, "couldn't insert popup menu" );
return TCL_ERROR;

After using the MNS_NOTIFYBYPOS flag and setting the MENUINFO of the created popup menu I expected to get WM_MENUCOMMAND messages, when selecting menu items, but I always get WM_COMMANDS.

Thanks for your reply!

Best Regards,

Martin Lemburg

prasad_som16-Feb-07 3:08

16-Feb-07 3:08

The problem , I see in your code is, you have applied MENUINFO, before inserting menu and submenus.

I tried on simple SDI application, creating a pop - up menu in resource, and using SetMenuInfo . It work like charm.

Prasad
Notifier using ATL | Operator new[],delete[][^]

Martin081516-Feb-07 3:56

16-Feb-07 3:56

Hello Prasad,

thanks for your engagement!

I changed my sources, so that ...

1. no MENUINFO action happens while creating the popup
2. the insertion is slightly changed:
2.1 menu->InsertMenu( itemPosition, ..., popup->m_hMenu, ... )
2.2 popup = menu->GetSubMenu( itemPosition )
2.3 requesting with popup->GetMenuInfo the MENUINFO to get the current dwStyle member => oldStyle
2.4 changing and setting with popup->SetMenuInfo the MENUINFO with dwStyle = oldStyle | MNS_NOTIFYBYPOS

I have introduced the ON_MESSAGE handler for WM_MENUCOMMAND, extended the CMainFrame::WindowProc and the CMainFrame::PreTranslateMessage, but none of them gets a WM_MENUCOMMAND message.

Even if a CMainFrame instance is the owner of the menu I insert my popups in, can I really be sure, that CMainFrame instance really receives the WM_MENUCOMMAND messages?

Thanks again and best regards,

Martin Lemburg

prasad_som16-Feb-07 5:00

16-Feb-07 5:00

Hi Martin,
You must be using TrackPopupMenu for invoking pop up menu, isn't it ?
Now, I'll tell you ,steps I followed to got it working.

1. Create a menu in resource editor with pop-up style.
2. Use CMenu::LoadMenu to load that menu.
3. Use SetMenuInfo as described in your original post.
4. Use TrackPopupMenu , set its parent as main frame window.
5. Override DefWndProc of CMainFrame(or you can use PreTranslateMessage).
6. I can see WM_MENUCOMMAND sent when clicked this menu.

May this give you some idea.

Prasad
Notifier using ATL | Operator new[],delete[][^]

Martin081516-Feb-07 6:31

16-Feb-07 6:31

Ok - got it working - a bit different than you told me to, and with a lot of consequences.

The current state:

1. we have a MFC application
2. our MFC application has a resource based menu, with one ON_COMMAND handler per menu item
3. I wrote a tcl API to access the MFC application menu, which allows to create new sub menus and menu items.
4. before I insert a popup menu, I switch the MFC application menu MENUINFO to MNS_NOTIFYBYPOS, so that WM_MENUCOMMAND messages are used, instead of WM_COMMAND messages
5. after inserting a popup menu, I switch the new sub menu to use WM_MENUCOMMAND messages
6. I registered a ON_MESSAGE handler for WM_MENUCOMMAND messages

The consequences:

1. None of the resource based menu items, with ON_COMMAND handlers, will work anymore, because there are no WM_COMMAND messages anymore
2. every selected menu item causes the wanted WM_MENUCOMMAND message
3. every menu in the "path" of (sub)menus seem to have this MENUINFO style flag MNS_NOTIFYBYPOS, so that this model is really working.
If I don't switch all containing menus of a sub menus to send WM_MENUCOMMAND messages, than the whole model won't work.
The suggestion above to use TrackPopupMenu must work, if the popup menu is used all alone, but if it is used inside a "path" of cascaded menus, than this would be more problematic.
4. the whole menu system of ON_COMMAND handlers must be rewritten, or I must find a way to get rid of the dummy or template menu item and create resources on the fly, but ... I don't know how!

A change of question:

How do I create on-the-fly resources or menu items with new, non-existing IDs?

If I'd know, how to create on-the-fly resources, than I could stay with the normal WM_COMMAND system.

Thanks to you Prasad!

Best regards, and a happy weekend!

Martin Lemburg

Debugging capability

mt_samiei15-Feb-07 22:39

mt_samiei

15-Feb-07 22:39

Dear All
I have following problem:
In a multi threaded application I want to debug my program.
But when I set break point one one thread, I find that all the threads are suspended. (In visual C++ 6 environment)
Is there any way to block the thread that we want to see its bahavior , without blocking other threads.

Regards

Mahdi

Re: Debugging capability

Cedric Moonen15-Feb-07 22:50

Cedric Moonen

15-Feb-07 22:50

I don't have an answer to your question but I really don't see why you want to do that ? Is there any particular reason to do that ?

Cédric Moonen
Software developer

Charting control [v1.1]

Re: Debugging capability

mt_samiei15-Feb-07 23:03

mt_samiei

15-Feb-07 23:03

One of my threads works with hardware, and an small time of disconnection will resutl in intefrace error with hardware.
Because of it.
Smile | :)

Re: Debugging capability

NiceNaidu15-Feb-07 23:07

NiceNaidu

15-Feb-07 23:07

chk this article.
http://www.codeproject.com/debug/xytrace.asp[^]

Appu..
"If you judge people, you have no time to love them."

kbhit() Question

Programm3r15-Feb-07 20:57

15-Feb-07 20:57

Hi all,

I have the following problem. I using a while loop, and if the user hits any key I prompt the user whether he/she wants to exit (Thats working ... awaiting previous thread). The problem comes in when the users selects No, when every loop cycle it asks the same question over and over again. How can I clear the buffer of the key board hit funtion ??

while(1)
{
    if(kbhit())
    {
        UINT msg_rc;
        msg_rc = MessageBox(NULL,"Are you sure you want to close the TCP/IP Server","Confirmation",MB_YESNOCANCEL);
        if (msg_rc == IDYES)
        {
           exit(1); // NEW....
           break;
        }
    }
....

Many thanx
Regards,

The only programmers that are better than C programmers are those who code in 1's and 0's..... Smile | :)

Programm3r

Re: kbhit() Question

Programm3r15-Feb-07 21:10

15-Feb-07 21:10

else
{
printf( "\nKey struck was '%c'\n", _getch() );
}

The only programmers that are better than C programmers are those who code in 1's and 0's..... Smile | :)

Programm3r

Re: kbhit() Question

prasad_som15-Feb-07 22:29

Re: kbhit() Question [modified]

15-Feb-07 22:29

I overlooked , that you got answer, reading printf statement in this post. And posted my reply.

Any way, use _getch(), at the start in if statement instead of else. So that it will be executed irrespective of condition.

Prasad
Notifier using ATL | Operator new[],delete[][^]

prasad_som15-Feb-07 21:54

15-Feb-07 21:54

Use _getch.

while(1)
{
 if(kbhit())
 {
_getch();
 UINT msg_rc;
 msg_rc = MessageBox(NULL,"Are you sure you want to close the TCP/IP Server","Confirmation",MB_YESNOCANCEL);
 if (msg_rc == IDYES)	
 {
exit(1); // NEW....
break;
 }
 }

-- modified at 4:18 Friday 16th February, 2007

Didn't noticed that you already got your answer, I ignore your second post, seeing its printf statement. Smile | :)

Prasad
Notifier using ATL | Operator new[],delete[][^]

Re: kbhit() Question

David Crow16-Feb-07 3:19

David Crow

16-Feb-07 3:19

Just out of curiosity, why are you using kbhit() and getch() with a GUI application? Those functions had their place with console applications, but with Windows, much more elegant solutions exist.

"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15

"Judge not by the eye but by the heart." - Native American Proverb

Messagebox Question

Programm3r15-Feb-07 20:47

15-Feb-07 20:47

Hi all,

I have the following piece of code that displays a messagebox, it's working and everything, but how can I display an icon in the message box. I am well aware of the MB_ICONEXCLAMATION, MB_ICONWARNING ... ext, but I want to use a yes - no button with a question mark icon:

msg_rc = MessageBox(NULL,"Are you sure you want to close the TCP/IP Server","Confirmation",MB_YESNOCANCEL);

Many thanx
Regards,

The only programmers that are better than C programmers are those who code in 1's and 0's..... Smile | :)

Programm3r

Re: Messagebox Question

toxcct15-Feb-07 20:52

toxcct

15-Feb-07 20:52

msg_rc = MessageBox(NULL,
                    "Are you sure you want to close the TCP/IP Server",
                    "Confirmation",
                    MB_YESNOCANCEL <code>| MB_ICONQUESTION</code>);

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Re: Messagebox Question

Programm3r15-Feb-07 20:57