C / C++ / MFC

Initializing data structure

28-Aug-02 21:32

as far as i have been able to tell, 'external dependencies' is a visual studio managed folder that lists all files included manually (via #include) that have not explicitly been added into the .h files.

try #including a header file not already in the project and rebuilding - it should then appear in the ext dep folder

Todd Smith28-Aug-02 8:31

Todd Smith

28-Aug-02 8:31

Is there a way to accomplish this?

I get an error the way it is now

error C2440: 'initializing' : cannot convert from 'const int' to 'int *'
Conversion from integral type to pointer type requires reinterpret_cast, C-style cast or function-style cast

int counts[] doesn't work either

warning C4200: nonstandard extension used : zero-sized array in struct/union
error C2233: '<unknown>' : arrays of objects containing zero-size arrays are illegal

typedef struct
{
	int id;
	int numCounts;
	int *counts;
} Counts;


Counts counts[] =
{
	{1,		0,		0},
	{2,		10,		{100, 101, 102, 103, 104, 105, 106, 107, 108, 109}},
	{3,		0,		0},
	{4,		0,		0},
	{5,		8,		{209, 208, 207, 206, 205, 204, 203, 202}},
	{6,		5,		{300, 301, 302, 303, 304}},
};

int numCounts = sizeof(counts) / sizeof(Counts);

void main()
{
        // loop through counts[]
	return;
}

Todd Smith

Maciej Pirog28-Aug-02 9:35

Maciej Pirog

28-Aug-02 9:35

You can't initialize pointer as an array like this:

int *a;
a = {10,20,30};

You can use only type identifier[] = { /*...*/ }

Pointers should be initialized like this:

int *a;
a = new int[10];
a[0] = 15;
a[]1 = 16;

I suggest you to create a more complex type.

Ñ There is only one MP Ð

Todd Smith28-Aug-02 12:42

Todd Smith

28-Aug-02 12:42

This worked

typedef struct
{
	int id;
	int numCounts;
	int *counts;
} Counts;

int items1[] = {100, 101, 102, 103, 104, 105, 106, 107, 108, 109};
int items2[] = {209, 208, 207, 206, 205, 204, 203, 202};
int items3[] = {300, 301, 302, 303, 304};

Counts counts[] =
{
	{1,		0,		0},
	{2,		10,		items1},
	{3,		0,		0},
	{4,		0,		0},
	{5,		8,		items2},
	{6,		5,		items3},
};

void main()
{
	return;
}

Todd Smith

Maciej Pirog29-Aug-02 2:34

Maciej Pirog

29-Aug-02 2:34

No! This code doesn't work well! It compiles with no errors, but int *counts; is still just a pointer and it can points only at the *first* element in an array!

Example:

int items1[] = {100, 101, 102, 103, 104, 105, 106, 107, 108, 109};
int* p = items1

in debugger:

Name:   value:    type:
p       0x0054H1  int*
|-      100       int

You can get access to the second element in an array like this: p++, but if you want to get access to the 11th element, you will get Access Violation and your program will crash!

Ñ There is only one MP Ð

jhwurmbach29-Aug-02 2:43

jhwurmbach

29-Aug-02 2:43

Maciej Pirog wrote:
You can get access to the second element in an array like this: p++, but if you want to get access to the 11th element, you will get Access Violation and your program will crash!

These are the ways of C++ Arrays. They *ARE* just pointer to some memory.
Maybe the STL std::vector is what you want?

Re: ON_MESSAGE .NET Issue

Maciej Pirog29-Aug-02 3:53

Maciej Pirog

29-Aug-02 3:53

jhwurmbach wrote:
Maybe the STL std::vector is what you want?

That's what I called "more complex type". Smile | :)

Ñ There is only one MP Ð

ON_MESSAGE .NET Issue

Ryan B.28-Aug-02 8:01

Ryan B.

28-Aug-02 8:01

I am opening and compiling some old code in Visual Studio .NET

I've run into a compiling problem..

BEGIN_MESSAGE_MAP(CChildView,CWnd )
	//{{AFX_MSG_MAP(CChildView)
	ON_WM_PAINT()
	ON_WM_CREATE()
	ON_WM_ERASEBKGND()
	ON_WM_SIZE()
	//}}AFX_MSG_MAP
	ON_MESSAGE(WM_FLIPWINDOW, OnFlipWindow)
END_MESSAGE_MAP()

tells me:
error C2440: 'static_cast' : cannot convert from 'void (__thiscall CChildView::* )(void)' to 'LRESULT (__thiscall CWnd::* )(WPARAM,LPARAM)'

whats happening here?
the Member Function is:
void CChildView::OnFlipWindow()

Ryan Baillargeon
Software Specialist
Fuel Cell Technologies Inc.

Fazlul Kabir28-Aug-02 8:46

Fazlul Kabir

28-Aug-02 8:46

MFC7 (in VS .NET) uses stricter type checking with message map macros. It looks like you need to replace the return from ‘void’ to ‘LRESULT’. Also make sure you supply the correct function parameters, such as (WPARAM, LPARAM) etc.
More on this here [click on Microsoft Foundation Class (MFC) link]

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vcedit/html/vcrefWhatsNewLibrariesVisualC70.asp[^]

Static Casting and MFC Message Maps Beginning with Visual C++ .NET, MFC provides stricter type checking for return and parameter types of message handler functions. This new behavior notifies the developer of potential problems by flagging potentially unsafe message handlers with an error message. MFC now uses static casts for ON_MESSAGE, ON_REGISTERED_MESSAGE, ON_THREAD_MESSAGE, and ON_REGISTERED_THREAD_MESSAGE.
For example, in the past a developer could use a member function that returned void instead of LRESULT for ON_MESSAGE or ON_REGISTERED_MESSAGE and compile without any errors. With Visual C++ .NET, the potential miscast is caught and flagged as an error. The developer can fix the potential problem by replacing the return type (with LRESULT) and recompiling.

Hope this helps.

// Fazlul

Get RadVC today! Play RAD in VC++
http://www.capitolsoft.com

Re: ON_MESSAGE .NET Issue

Nick Hodapp28-Aug-02 9:59

Nick Hodapp

28-Aug-02 9:59

FYI, this feature alleviates the #1 programmer bug in MFC code.

-Nick

This posting is provided “AS IS” with no warranties, and confers no rights. You assume all risk for your use. © 2001 Microsoft Corporation. All rights reserved.

Re: ON_MESSAGE .NET Issue

Michael Dunn28-Aug-02 12:28

Michael Dunn

28-Aug-02 12:28

Look at what the error is telling you. The compiler is expecting a function that takes two params, but you're giving it a function that takes no params. The return type is also wrong. Add the two standard message params (WPARAM and LPARAM) and correct the return value.

--Mike--
Just released - RightClick-Encrypt v1.4 - Adds fast & easy file encryption to Explorer
My really out-of-date homepage
Sonork-100.19012 Acid_Helm

How do I create a View and assing it his document class

Jose Cruz28-Aug-02 7:46

Jose Cruz

28-Aug-02 7:46

When you add a derived CView class to your MFC project how do I relate My View derived Class to my CDocument derived class.

I´m trying to add another view to my MFC project. Confused | :confused:

Re: How do I create a View and assing it his document class

Pavel Klocek28-Aug-02 11:03

Pavel Klocek

28-Aug-02 11:03

You do it in the InitInstance method of your CWinApp derived application class.
You will find there something like this:

CMultiDocTemplate* pDocTemplate;
pDocTemplate = new CMultiDocTemplate(
IDR_TESTDFTYPE,
RUNTIME_CLASS(CTestdfsdDoc),
RUNTIME_CLASS(CChildFrame), // custom MDI child frame
RUNTIME_CLASS(CTestdfsdView));
AddDocTemplate(pDocTemplate);

You register your new document/view pair by copy-paste-edit:

pDocTemplate = new CMultiDocTemplate(
IDR_MYTYPE,
RUNTIME_CLASS(CMyDoc),
RUNTIME_CLASS(CChildFrame), // custom MDI child frame
RUNTIME_CLASS(CMyView));
AddDocTemplate(pDocTemplate);

Don't forget to create document string in resources - see the string of existing document in string table resources for example (IDR_TESTDFTYPE in this case).

Sonork 100.15206;PavelK

Re: How do I create a View and assing it his document class

Pavel Klocek29-Aug-02 3:54

Pavel Klocek

29-Aug-02 3:54

Jose Cruz wrote:
Don't forget to create document string in resources - see the string of existing document in string table resources for example (IDR_TESTDFTYPE in this case).
First of all thank you for your help. Now do you have some explanation for the above phrase.

Every MFC document class has a corresponding definition string in string table resource - ID of the string is ID of the document (IDR_xxx), it defines parameters like name of the document for OLE, filename extension and so on.

You need one for every CDocument derived class in Your project. CDocTemplate class uses it.

It looks like:

NTGen\nNTGen\nNTGen\nNTGen Files (*.mdb)\n.mdb\nNTGen.Document\nNTGen Document

Sonork 100.15206;PavelK

CRichEditView without doc/view...

Anonymous28-Aug-02 7:40

Anonymous

28-Aug-02 7:40

Hello members,

i try to use the CRichEditView without doc/view architecture.

all works fine, but when i exit the app i get a fatal error.

Do anyone know about that error?

What i have maked:
-i created via app-wizard a SDI app without doc/viw
at the view i changed:
- all "things" from CWnd to CRichEditView
- and i have added macro for IMPLEMENT_DYNCREATE...

Can i use ever CRichEditView without doc/view?

Please help me, i really need help!

thanks

.dan.g.28-Aug-02 21:36

28-Aug-02 21:36

without more info about the fatal error (ie call stack), i suspect that the view is calling a CDocument function on a null pointer (because there is no document).

Anonymous29-Aug-02 9:47

Anonymous

29-Aug-02 9:47

Hello Dan,

thank you for your reply!

I don't have any skills at the doc/view... architecture. Can you please try to find the error in my app? (it's only a little testapp)

How can i upload the testapp to here? Or can i send it to you via enail?

I really need help, i tryed to fix that myself, but i don't have sucess.
And i wrote 3 post's about this on codeguru, and NONE reply to me.

Thank you very much!!!

Fiffi

.dan.g.1-Sep-02 13:55

1-Sep-02 13:55

i mailed you to zip it up and send it to me at dainelg@bde.com.au.

did you not receive it?

.dan.g.2-Sep-02 15:33

2-Sep-02 15:33

doh! that should have been danielg@bde.com.au