how to access form controls in another view - C / C++ / MFC Discussion Boards

David Crow11-Jun-04 2:17

11-Jun-04 2:17

As has already been mentioned, there is no need. What is it that you are doing that you think requires such a construct?

"When I was born I was so surprised that I didn't talk for a year and a half." - Gracie Allen

error! repeatedly calling the same MFC dialog box in vc++

shiva shankar10-Jun-04 20:59

shiva shankar

10-Jun-04 20:59

i am doing project on vc++ MFC DIALOG, where in i will be repeatedly calling the same dialog box morethan 100 times, but the problem is, that the dialog box is getting crashed(terminating or ending) after some 50 times..
what can be the problem?

Re: error! repeatedly calling the same MFC dialog box in vc++

Johan Rosengren10-Jun-04 21:13

Johan Rosengren

10-Jun-04 21:13

jklhjk wrote:
what can be the problem?

Probably that you have a bug in your program. As you don't describe anything about what the dialog does, it's difficult to be more specific Smile | :)

Have you tried running it in debug mode, you ought to get some more info on the reason this way?

Re: error! repeatedly calling the same MFC dialog box in vc++

shiva shankar10-Jun-04 22:00

shiva shankar

10-Jun-04 22:00

There is no bug in program,the same program i can run it in (c language) cmd prompt..

i have check it out by creating new dialog box ("hello")having only "OK" Buttton in it.

void CHelloDlg::OnOK()
{
// TODO: Add extra validation here
CDialog::EndDialog(IDOK);
CHelloDlg cmd(this);
cmd.DoModal();

}

after running it . keep pressing the "ok" button continously, the dialog box crashes or ends after 50 times..

Re: error! repeatedly calling the same MFC dialog box in vc++

Johan Rosengren10-Jun-04 22:19

Johan Rosengren

10-Jun-04 22:19

Are you trying to do some silly version of the obnoxious JavaScript-script popping up a messagebox forever ?

Anyway, your problem might not so much be the number of times you display a dialog, but rather the amount of dialogs displayed (and parented) at the same time. But the idea of popping up a new dialog - of the same kind - in response to a press on the OK-button - is in the best case silly, in the worst downright malicious.

As it is so easy to break out of the loop, by pressing Ctrl+Alt+Del, I'll suggest what you should do anyway:

1. Remove the code in the OnOK-handler, except for the call to the base class implementation.

2. Change the code originally creating the dialog to:

while( true ) {
  CHelloDlg cmd;
  cmd.DoModal();
}

3. Get a new hobby.

how to set font size to a particular item in Listcontrol box

Member 101812810-Jun-04 20:51

Member 1018128

10-Jun-04 20:51

Hai everyone,
I am doing a project using Listcontrol box.
In that i need some help,can any one tell me how to set font size for a particular item in a list controlbox.
for example,if i am adding a new item to the listcontrol box, it should appear bold. and other items shold be in normal font size.

Please help..

Thanks a lot. Rose | [Rose]

.in reading my question.

kailasam

Re: how to set font size to a particular item in Listcontrol box

Johan Rosengren10-Jun-04 21:17

Johan Rosengren

10-Jun-04 21:17

I think you will find http://www.codeproject.com/listctrl/lvcustomdraw.asp[^] instructive.

how to access form controls in another view

elephantstar10-Jun-04 20:36

elephantstar

10-Jun-04 20:36

Hi there,

I have a class called CChecklist that derives from CFormview and a checkmark image that I made invisible until the user finishes entry of another view called CFruits. How can I access IDC_CHECKMARK from CFruits class? I tried creating a object of class CChecklist to access its member function in order to change the visibility property of the control, but it gave me a run-time error. Please see below. How can I accomplish this?

void CCheckList::makeVisible()
{
GetDlgItem(IDC_CHECKMARK)->ShowWindow(TRUE);
}

void CFruits::OnOK()
{
CChecklist cl;
cl.makeVisible(); //run-time error
PostMessage(WM_COMMAND,ID_FILE_CLOSE);
}

Re: how to access form controls in another view

Johan Rosengren10-Jun-04 21:09

Johan Rosengren

10-Jun-04 21:09

makeVisible will try to find a child-control of CCheckList with the id IDC_CHECKMARK. Furthermore, you are creating an instance of CChecklist out of the blue - this instance has nothing to do with your other view/control.

You should not try to access controls between views, this makes it impossible to move one view to another application, and is considered Real Bad Programming. If you have two views, I assume that you have a single document holding both of them? In that case, the proper way to go about this is via the CDocument update-mechanism. You do this by calling CDocument::OnUpdateAllViews when you want to change stuff across view-boundaries, in (pseudo)code:

void CFirstView::SomeFunction()
{
  // some code making it necessary to change some control
  // in another view...

  CSomeDoc* pDoc = GetDocument();
  pDoc->UpdateAllViews( this, HINT_SOME_VALUE_YOU_DEFINE );

}

and in the recipient view, you add an update handler, so:

void CSecondView::OnUpdate(CView* pSender, LPARAM lHint, CObject* pHint) 
{
  if( lHint == HINT_SOME_VALUE_YOU_DEFINE )
  {
    // Do your stuff
  }
}

You should also get a basic textbook on C++, you'll have to learn the difference between a class and an instance of a class, for example. Lots of grief lies ahead if you don't know this Smile | :)

Re: how to access form controls in another view

elephantstar11-Jun-04 12:49

elephantstar

11-Jun-04 12:49

I did just as you suggested but I might have missed something. Here are my code samples just in case you can pinpoint the problem.

//Main application class
BOOL CMPSApp::InitInstance()
{
/* additional code present */
CMultiDocTemplate* pFirstView = new CMultiDocTemplate(
IDR_MAINFRAME,
RUNTIME_CLASS(CMyDoc), RUNTIME_CLASS(CMDIChildWnd),
RUNTIME_CLASS(CFirstView));
AddDocTemplate(pMHCEditDocTemplate);
CMultiDocTemplate* pFirstView = new CMultiDocTemplate(
IDR_MAINFRAME,
RUNTIME_CLASS(CMyDoc), RUNTIME_CLASS(CMDIChildWnd),
RUNTIME_CLASS(CSecondView));
AddDocTemplate(pMHCEditDocTemplate);
}

void CFirstView::OnOK()
{
if (g_selected == TRUE)
{
CDocument* pDoc = GetDocument();
pDoc->UpdateAllViews(NULL);
}
PostMessage(WM_COMMAND, ID_FILE_CLOSE);
}

void CSecondView::OnUpdate(CView* pSender, LPARAM lHint, CObject* pHint)
{
If (g_list->items.selected == 0)
{
GetDlgItem(IDC_APPLE)->ShowWindow(TRUE);
}
}

When UpdateAllViews() is called, there is only one view in the list and that is CFirstView, the calling view. Why does it not recognize the other views? Am I missing something? Thanks!

Re: how to access form controls in another view

Johan Rosengren14-Jun-04 8:56

Johan Rosengren

14-Jun-04 8:56

You are not only trying to send data between two views, they reside in different documents as well.

First, you have to get the doc templates from, the app, loop them and get the documents from each doc template. Well, it's easier to explain in code Smile | :)

POSITION templatePosition = AfxGetApp()->GetFirstDocTemplatePosition();
while( templatePosition != NULL )
{
	CDocTemplate* documentTemplate = AfxGetApp()->GetNextDocTemplate( templatePosition );
	if( documentTemplate )
	{
		POSITION documentPosition = documentTemplate->GetFirstDocPosition();
		while( documentPosition != NULL )
		{
			CDocument* document = documentTemplate->GetNextDoc( documentPosition );
			if( document )
				document->UpdateAllViews( NULL );
		}
	}
}

Now, OnUpdate will be called for all views.

Re: how to access form controls in another view

elephantstar14-Jun-04 13:01

elephantstar

14-Jun-04 13:01

It works beautifully! Thanks Johan!

Re: how to access form controls in another view

Johan Rosengren14-Jun-04 20:23

Johan Rosengren

14-Jun-04 20:23

My pleasure Smile | :)

Re: how to access form controls in another view

Cohen10-Jun-04 21:09

Cohen

10-Jun-04 21:09

The CChecklist object you create in the CFruits::OnOK() isn't the same you have subclassed somewhere else in your code. That object isn't subclassed at all and I suppose that this is why you get that runtime error.

You could try to do something like this (ain't that pretty though and I'm not sure does this work):

void CFruits::OnOK()
{

// Obtain handle to checklists parent here

HWND hCheckMark =
::GetDlgItem( ::GetDlgItem(handle_to_checklists_parent, IDC_CHECKLIST), IDC_CHECKMARK );

::ShowWindow( hCheckMark, SW_SHOW );
PostMessage(WM_COMMAND,ID_FILE_CLOSE);
}

Cohen

CDialog1Dlg Class is not appeared in class view tab.

Rajesh_K_Sharma10-Jun-04 19:04

Rajesh_K_Sharma

10-Jun-04 19:04

Hi I made a project of Dialog box using MFC.My Project name is Dialog1.All Operations I have done.Finally I Select the ClassView tab from the project workspace pane.CDialog1Dlg
class is not appeared in calss veiw tab.
I would like to know that "how to get CDialog1Dlg class " in class view tab.

rajesh

Re: CDialog1Dlg Class is not appeared in class view tab.

*Dreamz10-Jun-04 19:15

*Dreamz

10-Jun-04 19:15

Go to the Dlg class header file.Make some change there..
( Just give a blank line after class declaration Wink | ;)

)
Check the class view.

Re: CDialog1Dlg Class is not appeared in class view tab.

ThatsAlok11-Jun-04 5:19

ThatsAlok

11-Jun-04 5:19

Hian buddy close your project and now sercah for your projectname.ncb file and delete the file
now reopen yiour dsw file you Class CDialog1Dlg visible in class view

I Think It will Work
Alok Gupta
visit me at http://www.thisisalok.tk

sending a packet of data to a server

Anonymous10-Jun-04 19:02

Anonymous

10-Jun-04 19:02

Hello,
I want to send a packet of data to a web server on port 80. How exactly would I go about doing this.

Re: sending a packet of data to a server

bikram singh10-Jun-04 19:24

bikram singh

10-Jun-04 19:24

Take a look at the InternetXXXXXX() and HttpXXXXXX() functions in MSDN such as:

InternetOpen, InternetConnect, HttpOpenRequest, HttpSendRequest etc.

Bikram Singh

Re: sending a packet of data to a server

Anonymous10-Jun-04 19:30

Anonymous

10-Jun-04 19:30

thank you. But how exactly would i implement this into code. Could you give me some source for a program that sends a packet of data to a web server Big Grin | :-D

VC++ : Registry

10-Jun-04 18:34

Hi,

Is there any way to convert a HKEY value to it's corresponding registry key name?i.e how do you convert (HKEY) 0x80000000 to HKEY_CLASSES_ROOT ? Confused | :confused:

Re: VC++ : Registry

bikram singh10-Jun-04 18:52

bikram singh

10-Jun-04 18:52

HKEY_CLASSES_ROOT is a macro, defined as
#define HKEY_CLASSES_ROOT ((HKEY)0x80000000)

Do you need to "convert" it to a string?
Instead of using the long-drawn-out switch() statement approach, do it this way:

<br />
#define MAKE_SZ(something) #something <br />
<br />
const char *szHKCR = MAKE_SZ(HKEY_CLASSES_ROOT);<br />
<br />
printf("\n%s",szHKCR);<br />

The 'something' in the macro parameter can be 'anything'. It need not be a pre-defined macro like HKEY_CLASSES_ROOT is. For example, the following will also work:

<br />
const char *Dummy = MAKE_SZ(uioiasdhfkjasdhf);<br />
<br />
printf("\n%s",Dummy);<br />

HTH

Bikram Singh

Re: VC++ : Registry

Member 102316912-Jun-04 16:10

Member 1023169

12-Jun-04 16:10

Dear Vikram ,
Your method works fine for predefined keys like HKEY_LOCAL_MACHINE etc.But what about HKEY values returned by functions like RegOpenKey,RegCreateKey ? Eg:

RegOpenKey(HKEY_CURRENT_CONFIG,TEXT("Software\\Fonts"),&hKey) returns an integer value in hKey.I want to somehow get the keyname "HKEY_CURRENT_CONFIG\Software\Fonts" from the value in HKEY .
Any suggestions???????????? Confused | :confused:

Jesus H Christ !!!!!!

bikram singh13-Jun-04 1:20

bikram singh

13-Jun-04 1:20

My name is BIKRAM, dude.

While I can, possibly, with difficulty, attempt to find out the keypath from a handle-value, its not worth the trouble.

It seems you have either a design problem or are attempting to intercept a function call from a process. In either case, you will need to re-think your strategy. I could help you in this, but i do knot know exactly what you want to accomplish and why.

Bikram Singh

How to display images dynamically

Neeranjan10-Jun-04 18:23

Neeranjan

10-Jun-04 18:23

Hi friends,

I am trying to devlop a Single Document (Document/View Architecture) MFC application, which has Three frames. Left frame has a Hierarchy tree and on selection of any leaf node, number (not fixed) of images be displayed on the right upper frame (four picture per row) dynamically as shown below.

---------------------------------------
| | |
| | |
| Tree | Images |
| | |
| | |
| |-----------------------------
| | |
| | Discription |
| | |
--------- -----------------------------
On click of an image its description should be displayed in right lower frame

My first priority is to display images dynamically.
Example: when there are 10 images, it should display 4 in first row, 4 in second row and last 2 in third row.

If any material/example/sample code/suggestion, Please reply me.

I need it very argently. Please help me.

Thanx

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.