C / C++ / MFC Discussion Boards

disable a submenu item on runtime in an MFC app

caykahve25-Jul-04 23:35

25-Jul-04 23:35

Hi,

To disable and enable a submenu item on runtime in an MFC app, I have used the following

code but seen no change. What is the problem with it?

MSDN says m_bAutoMenuEnable should be set to FALSE in the constructor of CMainFrame (in CMenu::EnableMenuItem), but in CDialog class there doesn't seem to be such a variable, or is there?

If I have to use ON_UPDATE_COMMAND_UI, can you give me some information on what to do?

Thanks...

// I want to disable the item "F" in the Settings Submenu, which has the ID ID_SETTINGS_F 
// File   Settings   Help
// A      B          C
// D      E    
//        F

// disable
CMenu* pMenu, *subMenu;	
pMenu = AfxGetMainWnd()->GetMenu();	
subMenu = pMenu->GetSubMenu(1);
subMenu->EnableMenuItem(ID_SETTINGS_F, MF_BYPOSITION | MF_DISABLED | MF_GRAYED);	
DrawMenuBar();
//

//enable
//...the same as above
subMenu->EnableMenuItem(ID_SETTINGS_F, MF_BYPOSITION | MF_ENABLED);
//...the same as above

Re: disable a submenu item on runtime in an MFC app

Anonymous25-Jul-04 23:45

Anonymous

25-Jul-04 23:45

i m trying to understand ur problem. if i m correct, u want to disble some submenu item on some event occuring. ur code seems to be perfectly OK. i guess u can remove the statement
DrawMenuBar();
i hope it will work. as it works in my application

Re: disable a submenu item on runtime in an MFC app

caykahve25-Jul-04 23:52

caykahve

25-Jul-04 23:52

Yes, i want to disable the submenu item on some event and enable it on some other event. However the code does not work with or without DrawMenuBar(); The menu does not get affected at all.

Should I do something with the UPDATE_COMMAND_UI?

Re: disable a submenu item on runtime in an MFC app

V.25-Jul-04 23:47

25-Jul-04 23:47

Maybe something like this:

//add event handler to menu item.

void PbmFlexListViewer::OnUpdateYourMenuItem(CCmdUI *pCmdUI){<br />
        //bool benable = true/false<br />
	pCmdUI->Enable(bEnable);<br />
}										//end function OnUpdateYourMenuItem

good luck!

"If I don't see you in this world, I'll see you in the next one... and don't be late." ~ Jimi Hendrix

Re: disable a submenu item on runtime in an MFC app

caykahve26-Jul-04 0:24

caykahve

26-Jul-04 0:24

Could not make it grayed, but is disabled right now.

I use this code and threw away the preivous things!

//to enable<br />
settingsF_Enable = TRUE;<br />
<br />
//to disable<br />
settingsF_Enable = TRUE;<br />
<br />
void MyDlg::OnUpdateSettingsF(CCmdUI* pCmdUI) <br />
{<br />
   pCmdUI->Enable(settingsF_Enable);<br />
}

I hope somebody could tell me how to make it gray. Confused | :confused:

There must be something to be added in the OnUpdateSettingsF() function, but I couldn't find how to call the pointer to the menu item and call EnableMenuItem() with MF_GRAYED

multiple text in status-bar

Anonymous25-Jul-04 23:21

Anonymous

25-Jul-04 23:21

i have created a status bar in my dialog based application.

the code is below:-

#define IDC_STATUSBAR 32000 //resource id

CStatusBarCtrl m_StatBar;

BOOL m_bStatOK = m_bStatBar.Create(WS_CHILD | WS_BORDER | WS_VISIBLE, rect, this, IDC_STATUSBAR);
m_StatBar.SetText("Application Running",0,0);

The program is running fine. the text is shoen on the left hand side of the status bar. Now i want to display another text on the right hand side of the statusbar. how do i do? i tried by inserting the statement

m_StatBar.SetText("Time",255,0);
But it had no impact?
how do i proceed? Smile | :)

Position the mouse on a web browser programmatically

yourbuddy7725-Jul-04 21:22

yourbuddy77

25-Jul-04 21:22

I want to change the position of mouse on an internet explorer window.I have tried the code below.The problem is that hr = pDoc4->createEventObject(NULL,&pEvtObj) fails.Because of this failure there is no point proceeding with the remaining code.Can you tell me the reason for this failure.Thanks in advance.

//For changing mouse position
IHTMLEventObj *pEvtObj = NULL;
IHTMLDocument4 *pDoc4 = NULL;
hr = m_pHTMLDoc->QueryInterface(IID_IHTMLDocument4,(void**)&pDoc4);//m_pHTMLDoc is a valid document pointer
if(SUCCEEDED(hr))
{
// VARIANT vEvt;
// VariantInit(&vEvt);
// vEvt.vt = VT_DISPATCH;
// vEvt.pdispVal = NULL;

hr = pDoc4->createEventObject(NULL,&pEvtObj);
if(SUCCEEDED(hr))
{
CComQIPtr<ihtmleventobj2, &iid_ihtmleventobj2=""> pEvtObj2;

pEvtObj2 = pEvtObj
Xpos = 100;
Ypos = 200;
g_Ypos = g_lastYpos = Ypos;
hr = pEvtObj2->put_clientX(Xpos);
if(hr == 0)
{
AfxMessageBox("put_clientX successful");
}
else
{
AfxMessageBox("put_clientX failed");
}
hr = pEvtObj2->put_clientY(Ypos);

// }

// pEvtObj->Release();
}
pDoc4->Release();
}

line comparison on word basis

mfc_surfer25-Jul-04 20:46

mfc_surfer

25-Jul-04 20:46

I need and algorithm or a sample code to compare two lines on word basis and show added/deleted/changed words within lines during comparison.
Any suggestion would be appreciated.

Thanks

dynamically create controls and attaching listeners to them?

misterbear25-Jul-04 20:23

misterbear

25-Jul-04 20:23

Hello, I don't know if this is super-easy to accomplish,
I am pretty new to VC++/MFC..

I need to create a dialog which must contain a different number
of CButton controls depending on certain state parameters of the
application. So I need to dynamically create a number of those
controls and attach a message handler for them ( they all share
the same message handler code ).

How do I attach this listener function to the controls once
I've created them?
(I destroy all buttons and create a bunch of new ones when the layout changes)

thankful for any help.

Re: dynamically create controls and attaching listeners to them?

KarstenK25-Jul-04 21:14

KarstenK

25-Jul-04 21:14

Why dont you enable/disable or show/hide the controls at runtime, it is also better by UI Design-Guidelines.
-> Make a full dialog with all resources in the resource editor, assign control objects to all controls and work with mycontrol.EnableWindow( bActiveNow ) Cool | :cool:

Try this @ home. (B&B)

But how to attach a message handler dynamically?

misterbear26-Jul-04 0:04

misterbear

26-Jul-04 0:04

I've thought of that as well.
But I really don't have a clue as of what the maximum number of controls is. I could of
course create a ridiculously large amount of CButton objects to be on the safe side, and just
hide/show those. But it sounds a bit unneccessary to me...

And I'm still very much interested in attaching a message handler dynamically. Can I for example
create a hook and install it for every new item? And in that hook listen for the BN_CLICKED event
and if one is received obtain the text for the control and pass it further on?

If so, how is a hook procedure attached?

dynamically create controls and attaching listeners to them?

misterbear25-Jul-04 20:23

misterbear

25-Jul-04 20:23

Hello, I don't know if this is super-easy to accomplish,
I am pretty new to VC++/MFC..

I need to create a dialog which must contain a different number
of CButton controls depending on certain state parameters of the
applications. So I need to dynamically create a number of those
controls and attach a message handler for them ( they all share
the same message handler code ).

How do I attach this listener function to the controls once
I've created them?
(I destroy all buttons and create a bunch of new ones when the layout changes)

thankful for any help.

GDI Objects

0v3rloader25-Jul-04 13:25

0v3rloader

25-Jul-04 13:25

Hello,

Can a GDI object be created once (say when the class is constructed) and be used as many times as the programmer is pleased?

Example:

Class::Class()
{
	myPen = CPen(....);
}

void Class::DrawThis()
{
	pDC = new CDC();
	pDC -> Attach(GetDC() -> GetSafeHdc());
	pDC -> SelectObject(&myPen);
}

Is this valid and recommended?

dNimrod#X
________________________

Re: GDI Objects

Ravi Bhavnani25-Jul-04 14:54

Ravi Bhavnani

25-Jul-04 14:54

Yes, but I don't recommend it because it can be hard(er) to maintain code that shares GDI objects. The only time I'd keep a GDI object around for the lifetime of my app is when it's very expensive to create one on the fly.

One other thing - DrawThis() should unselect myPen when it's done using it. For example:

void Class::DrawThis()
{
  CPen* pOldPen = pDC->SelectObject (&myPen);
  ...
  pDC->SelectObject (pOldPen);
}

/ravi

My new year's resolution: 2048 x 1536
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Re: GDI Objects

Michael Dunn25-Jul-04 18:21

Michael Dunn

25-Jul-04 18:21

I disagree with Ravi, if you are going to use a GDI object a lot, I say create it once and just keep using it. The exception is device contexts (CDC and related classes) - DCs are a shared and scarce system resource, and CDCs should exist for only as long as you need them.

Your sample code is wrong, however, in the way it's using CDC. You need to match GetDC() and ReleaseDC() calls, as well as select the pen out of the DC before releasing it.

--Mike--
Personal stuff:: Ericahist | Homepage
Shareware stuff:: 1ClickPicGrabber | RightClick-Encrypt
CP stuff:: CP SearchBar v2.0.2 | C++ Forum FAQ
----
#include "witty-quote.h"

Re: GDI Objects

Antony M Kancidrowski26-Jul-04 2:06

Antony M Kancidrowski

26-Jul-04 2:06

... Additionally to the other comments. If you are using multiple threads to access GDI objects then take a look at the following MSDN article.

MTGDI Sample: Demonstrates Sharing GDI Resources Across Multiple Threads of Execution[^]

Ant.

I'm hard, yet soft.
I'm coloured, yet clear.
I'm fruity and sweet.
I'm jelly, what am I? Muse on it further, I shall return! - David Williams (Little Britain)

Readfile from *.txt

71cwill25-Jul-04 8:39

71cwill

25-Jul-04 8:39

I have been trying to create a tokeninzer/scanner for my school project. But I have a hard time dealing with spaces between words. rather than it would separates the words after spaces, it will keep on adding the characters to one big word. If I inputed "print codes", it will make the variables as one 'printcodes' rather than "print" as one keyword and "codes" as identifier.
Could anyone help me solve this problem?
Here is the c++ codes I created:
while(!read.eof()) //(read>>letter)
{
//catching symbols
if(letter == '*'||'/'||'+'||'-'||'='||'('||')') {
checkid.checktokenop(letter); }
char gotit2 = letter;
//catching letters
if(gotit2 != '*')
if(gotit2 != '/')
if(gotit2 != '+')
if(gotit2 != '-')
if(gotit2 != '=')
if(gotit2 != '(')
if(gotit2 != ')')
{
int result = 1;
codes+= gotit2;
if(gotit2 == ' ')
{
result = checkid.checktokenword(codes);
codes.erase();
}
if(result == 0)//if Reserved word and,or,print,not
{
codes.erase();
}
}//end of catching letter
}

Please help!!!

Re: Readfile from *.txt

Michael Dunn25-Jul-04 11:33

Michael Dunn

25-Jul-04 11:33

71cwill wrote:
if(letter == '*'||'/'||'+'||'-'||'='||'('||')')

The first problem is that's not how you test for multiple vaules. You need to do:

if ( letter == '*' || letter == '/' || /*and so on...*/ )

--Mike--
Personal stuff:: Ericahist | Homepage
Shareware stuff:: 1ClickPicGrabber | RightClick-Encrypt
CP stuff:: CP SearchBar v2.0.2 | C++ Forum FAQ
----
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Disabling/enabling menu/toolbar items...

0v3rloader25-Jul-04 7:14

0v3rloader

25-Jul-04 7:14

Hello,

How does one do about disabling/enabling a menu and toolbar item that share the same ID?

Thanks a million,

David

Re: Disabling/enabling menu/toolbar items...

Ivan Cachicatari25-Jul-04 11:44

Ivan Cachicatari

25-Jul-04 11:44

Hi,

You can to obtain it adds an event to UPDATE_COMMAND_UI message, associated to this ID, with ClassWizard.

<br />
void CMainFrame::OnYourEvent(CCmdUI* pCmdUI) <br />
{<br />
   pCmdUI->Enable(m_bFlag);<br />
}<br />

the m_bFlag is a bool variable to manage the enabing/disabling.

Ivan Cachicatari
www.latindevelopers.com

Re: Disabling/enabling menu/toolbar items...

0v3rloader25-Jul-04 11:57

0v3rloader

25-Jul-04 11:57

Hi, thanks for the reply!

Can you tell me how to enable/disable an item without having to wait for the event to fire?

I mean, what is the way to do it manually?

Re: Disabling/enabling menu/toolbar items...

Ravi Bhavnani25-Jul-04 13:33

Ravi Bhavnani

25-Jul-04 13:33

dNimrod#X wrote:
without having to wait for the event to fire?

The event is sent during the app's idle processing. You don't have to do anything special - just set the appropriate bool variable to false and query it in the UI update handler. Try it - you'll like it!

/ravi

My new year's resolution: 2048 x 1536
Home | Articles | Freeware | Music
ravib@ravib.com

Solution for globally listening to keys pressed

0v3rloader25-Jul-04 6:59

0v3rloader

25-Jul-04 6:59

Hi there,

I have this application which opens different modeless dialog boxes and has some accelerators defined.

My question is assuming a window/control/... has the focus at the time, how can the C[...]App know the user pressed a key? Basically, what I am trying to do is make the app process certain accelerators, independently of the window that has the focus.

Re: Solution for globally listening to keys pressed

PJ Arends25-Jul-04 10:13

PJ Arends

25-Jul-04 10:13

The easiest way is to use a "hot key". See RegisterHotKey.

"You're obviously a superstar." - Christian Graus about me - 12 Feb '03

"Obviously ??? You're definitely a superstar!!!" mYkel - 21 Jun '04

Within you lies the power for good - Use it!

how to pass a simple char* to a unicode binary text??

youpiyoyo25-Jul-04 5:45

youpiyoyo

25-Jul-04 5:45

My purpose is to pass an icon to the resource of a file or dll. If you have any sugestions..

for that I have to use UpdateResource

so I did that

hUpdateRes = BeginUpdateResource("D:\\Bureau\\ressource\\test resource\\test resource.exe", FALSE); <br />
if (hUpdateRes == NULL) <br />
{ <br />
    MessageBox(0,"Could not open file for writing.",0,0); <br />
} <br />
 <br />
// Add the dialog box resource to the update list. <br />
result = UpdateResource(hUpdateRes,RT_ICON,szTitre,MAKELANGID(LANG_NEUTRAL,SUBLANG_NEUTRAL),ico,1384); // size of resource info. <br />
if (result == FALSE) <br />
{ <br />
    MessageBox(0,"Could not add resource.",0,0); <br />
} <br />
 <br />
<br />
if (!EndUpdateResource(hUpdateRes, FALSE)) <br />
{ <br />
    MessageBox(0,"Could not write changes to file.",0,0); <br />
}

1384 reprsente the exact size of the ico, I will chage it with sizeof or somethingelse

my problem is ico

acording to msdn ico, so the LPVOID lpData must be in "raw binary data" and the "text must be in Unicode format"

so I try that

char* ico;<br />
wchar_t *wchar=(wchar_t *)malloc( sizeof( wchar_t ) );<br />
<br />
_setmode( _fileno( stdin ), _O_BINARY ); <br />
FILE* file=fopen(szFile,"rb");<br />
FILE* filedest=fopen("dest.ico","w");<br />
fpos_t pos;<br />
if(fseek(file, 0,SEEK_END)!=0)MessageBox(0,"fseek erreur",0,0);<br />
else<br />
{<br />
	if( fgetpos( file, &pos ) == 0 )<br />
	{<br />
<br />
		ico=(char*) malloc((size_t)pos);<br />
		fseek(file, 0,SEEK_SET);<br />
		fread(ico, sizeof( char ), (int)pos, file );<br />
		//wctomb(&ico,wchar);<br />
		mbtowc( wchar ,ico,MB_CUR_MAX );<br />
	}<br />
}<br />
fclose(file);<br />
fclose(filedest);

I'm not sure about the mbtowc, ...

If have no clue to pass ico in "raw binary data and in Unicode format"

Pleazeeeeeeee help me!!

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