C / C++ / MFC Discussion Boards

vikas amin21-Dec-05 0:50

21-Dec-05 0:50

I tried to initalise a structure in the class
by

struct tagBITMAPFILEHEADER
{
WORD bfType=0; // must be 'BM'
DWORD bfSize=0; // size of the whole .bmp file
WORD bfReserved1=0; // must be 0
WORD bfReserved2=0; // must be 0
DWORD bfOffBits=0;
}m_BITMAPFILEHEADER ;

there is an error displayed as

error C2252: 'bfType' : pure specifier can only be specified for functions

How to initialise in a class any help

Vikas Amin
Embin Technology
Bombay
vikas.amin@embin.com

Re: Initializing Structure in a class

Rage21-Dec-05 1:11

Rage

21-Dec-05 1:11

vikas amin wrote:
How to initialise in a class

Is this working?

struct tagBITMAPFILEHEADER 
{
WORD bfType; // must be 'BM' 
DWORD bfSize; // size of the whole .bmp file
WORD bfReserved1; // must be 0
WORD bfReserved2; // must be 0
DWORD bfOffBits;
}m_BITMAPFILEHEADER = {0,0,0,0,0};

~RaGE();

Re: Initializing Structure in a class

Owner drawn21-Dec-05 1:13

Owner drawn

21-Dec-05 1:13

vikas amin wrote:
WORD bfType=0; // must be 'BM'
DWORD bfSize=0; // size of the whole .bmp file
WORD bfReserved1=0; // must be 0
WORD bfReserved2=0; // must be 0
DWORD bfOffBits=0;

You cannot init members like that inside a structure.

Create an instance and then initialize the members

Happy christmas friends. May the Love of My Lord and Saviour Jesus bring forth Joy and Happiness into your life too.
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--Never say quits
--Jesus is Lord

Re: Initializing Structure in a class

toxcct21-Dec-05 2:03

toxcct

21-Dec-05 2:03

to be more complete, writing such a thing tell the compiler that the members are pure virtual (which is here definitely wrong).

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

Re: Initializing Structure in a class

Owner drawn21-Dec-05 19:44

Owner drawn

21-Dec-05 19:44

Game over

Re: Initializing Structure in a class

Eytukan21-Dec-05 2:01

Eytukan

21-Dec-05 2:01

in the constructor , init the strcut variable = {val,val2,...).(positional refernce)

"But your mind is very complex, very tricky. It makes simple things complicated. -- that's its work. And for centuries it has been trained for only one thing: to make things so complicated that your life becomes impossible."- Osho

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--[V]--

Re: Initializing Structure in a class

toxcct21-Dec-05 2:13

toxcct

21-Dec-05 2:13

Mr vikas,

it's the second time i see this question from you. if you continue asking it exactly the same way, you will get exactly same answers...

to go further in help, i'd like to see how you exactly try to initialize your struct (give a piece a code were you do it, and DON'T FORGET : round your code samples with <pre></pre> tag to help us see you code better !!)

moreover, as it has already been suggested, there are 2 ways to do this :
1st :

m_BITMAPFILEHEADER = { 0, 0, 0, 0, 0 };

2nd :

m_BITMAPFILEHEADER.bfType      = 0;
m_BITMAPFILEHEADER.bfSize      = 0;
m_BITMAPFILEHEADER.bfReserved1 = 0;
m_BITMAPFILEHEADER.bfReserved2 = 0;
m_BITMAPFILEHEADER.bfOffBits   = 0;

if you try to initialize this in your class constructor, did you try also to use the first method in the initilizer list of the constructor ?

<font color=blue>class</font> MyClass {
  <font color=blue>private</font>:
    <font color=blue>struct</font> tagBITMAPFILEHEADER {
        <font color=green>//...</font>
        tagBITMAPFILEHEADER(<font color=blue>const</font> tagBITMAPFILEHEADER&);  <font color=green>//Default constructor</font>
    } m_tagBITMAPFILEHEADER;
 
  <font color=blue>public</font>:
    MyClass()
        : m_tagBITMAPFILEHEADER({ 0, 0, 0, 0, 0 }) {
        <font color=green>//...</font>
    }
};

TOXCCT >>> GEII power
[toxcct][VisualCalc 2.20][VisualCalc 3.0]

Re: Initializing Structure in a class

krmed21-Dec-05 4:37

krmed

21-Dec-05 4:37

You could write a constructor into the structure itself, so whenever that structure is created, it's properly initialized:

struct tagBITMAPFILEHEADER 
{
    WORD bfType; // must be 'BM' 
    DWORD bfSize; // size of the whole .bmp file
    WORD bfReserved1; // must be 0
    WORD bfReserved2; // must be 0
    DWORD bfOffBits; 
    tagBITMAPFILEHEADER::tagBITMAPFILEHEADER()
    {
        bfType = 0;
        bfSize = 0;
        bfReserved1 = 0;
        bfReserved2 = 0;
        bfOffBits = 0;
    }
};

Now you could have in your header:

tagBITMAPFILEHEADER *m_pBMHeader;

and when you create it

m_pBMHeader = new tagBITMAPFILEHEADER;

the constructor will be called and your values will be initialized.

Hope that helps.

Karl - WK5M
PP-ASEL-IA (N43CS)
<kmedcalf@ev1.net>
PGP Key: 0xDB02E193
PGP Key Fingerprint: 8F06 5A2E 2735 892B 821C 871A 0411 94EA DB02 E193

Offer user a list of choices from a command prompt

KevinSheedy21-Dec-05 0:16

KevinSheedy

21-Dec-05 0:16

I want to offer a user a list of folders to choose from. The user should be able to use the arrow keys to scroll up and down so that the current choice is highlighted. They should also be able to choose using the number keys.
Thanks

KevinSheedy

Re: Offer user a list of choices from a command prompt

khan++21-Dec-05 3:48

khan++

21-Dec-05 3:48

To get a list of folders, you could use _findfirst(), _findnext() etc to get the needed folder list.
A- Display the list using printf(), cout etc.
B- Write a while loop which takes input from the user, and interprets the key pressed. (you could use getch()).
C- Highlight the current selection. (Now that is a problem):
1- You could put some special character ahead of the selected line.
2- You could dig deep into VC and find just the right technique to change the backcolor of the text, or the text itself. (If it is possible)
3- Something else.

Is that your homework?

this is this.

Re: Offer user a list of choices from a command prompt

KevinSheedy21-Dec-05 4:10

KevinSheedy

21-Dec-05 4:10

Hi. Thanks, that helps. I guess the highlighting part isn't all that important. You know when windows gives you the option to boot from safe mode, safe mode with CD support or boot normally etc. It lets you scroll up and down with the arrows. I just thought there might be some simple function that lets you do that. If there's no easy way, I can just prompt the user to pick a number or something like that. It's not worth wasting too much time over.

KevinSheedy

Re: Offer user a list of choices from a command prompt

khan++21-Dec-05 4:27

khan++

21-Dec-05 4:27

Just a little comment:
The windows menu that appears comes from real-mode DOS (I think) Smile | :)

So, there are endless possibilites of what you can do with real-mode DOS OS; you can write directly to memory, set the foreground and background colors, blink text, ... anything. But with protected mode OSes, they don't let you write directly to any arbitrary memory location. Cry | :((

this is this.

Re: Offer user a list of choices from a command prompt

RChin21-Dec-05 6:20

RChin

21-Dec-05 6:20

Just adding to what Khan++ said. Programming for the DOS window is a different programming style than the even driven windows framework. If you used to program in Turbo C++, there used to be a library (conio.h) that allowed you to manipulate the console window. But you still had to do the hard work if you wanted to simulate UI things like menu selection.
You can still do this in a Windows Console program using the console functions. Take at look at this[^] to start with.

I Dream of Absolute Zero

FindResource -Problem

kotiramkoteswararao20-Dec-05 23:53

kotiramkoteswararao

20-Dec-05 23:53

Hi,

Here is the code ,what i am using

HMODULE hmod;

HRSRC hr;

HGLOBAL gm;

char* lock;

hmod=LoadLibrary("testdll.dll");

hr=FindResource(hmod,MAKEINTRESOURCE(504),"GIF");

gm=LoadResource(hmod,hr);

lock=(char *)LockResource(gm);

if(hr == NULL)

MessageBox("This is not working");

else

MessageBox("This is working");

Here ,in this testdll.dll, we have stored Gif file as a resource and 504 is the resource identifier number. The resource type is "GIF".

But its not working. plz suggest me the solution

--
Regards,

RamakoteswaraRao Koti

spend every minute for success

Re: FindResource -Problem

includeh1021-Dec-05 2:23

includeh10

21-Dec-05 2:23

I can not remember exact code, but the fuction call
hr=FindResource(hmod,MAKEINTRESOURCE(504),"GIF");
is not correct.

you can try enumurating resource to find its resource ID.

includeh10

How can I add a status bar to a dialog.....

Owner drawn20-Dec-05 23:53

Owner drawn

20-Dec-05 23:53

How can I add a status bar to a dialog.

I can add a toolbar but status bar is not showing up. It is being created successfully.

Happy christmas friends. May the Love of My Lord and Saviour Jesus bring forth Joy and Happiness into your life too.
<marquee direction="up" height="30" scrolldelay="1" step="1" scrollamount="1" hspace="0" vspace="0">
--Owner Drawn
--Nothing special
--Defeat is temporary but surrender is permanent
--Never say quits
--Jesus is Lord

Re: How can I add a status bar to a dialog.....

Owner drawn21-Dec-05 0:08

Owner drawn

21-Dec-05 0:08

LOL

I've Done It.

He he. Laugh | :laugh:

Re: How can I add a status bar to a dialog.....

Ward21-Dec-05 0:13

Ward

21-Dec-05 0:13

Try using InitCommonControls or InitCommonControlsEx in the beginning of your program.

INITCOMMONCONTROLSEX InitCtrls;<br />
InitCtrls.dwSize = sizeof(INITCOMMONCONTROLSEX);<br />
InitCtrls.dwICC = ICC_BAR_CLASSES;	<br />
InitCommonControlsEx(&InitCtrls);//also check the returnvalue of this API

If it still does not work, you should try to add it through code:

hStatus = CreateWindowEx(0, STATUSCLASSNAME, NULL,<br />
        WS_CHILD | WS_VISIBLE | SBARS_SIZEGRIP, 0, 0, 0, 0,<br />
        hwnd, (HMENU)IDC_MAIN_STATUS, GetModuleHandle(NULL), NULL);<br />
int statwidths[] = {100, -1};<br />
SendMessage(hStatus, SB_SETPARTS, sizeof(statwidths)/sizeof(int), (LPARAM)statwidths);<br />
SendMessage(hStatus, SB_SETTEXT, 0, (LPARAM)"Some text");

kind regards,

Ward

Re: How can I add a status bar to a dialog.....

Rage21-Dec-05 1:12

Rage

21-Dec-05 1:12

Here the well known Nish article :

Link[^]

~RaGE();

Thanks a lot guys

Owner drawn21-Dec-05 1:56

Owner drawn

21-Dec-05 1:56

Subclassed MFC CHeaderCtrl does only receive WM_NOTIFY in Debug

WernerP20-Dec-05 23:51

WernerP

20-Dec-05 23:51

Hi,

(1) I have a CRszListCtrl : public CListCtrl

(2) which has a CustHeaderCtrl m_hdrCustom, where CustHeaderCtrl : public CHeaderCtrl

(3) CRszListCtrl has init() called from CDialog::OnInitDialog.

(4) This init() calls void CustHeaderCtrl::init(CListCtrl * const pList) with Argument this (i.e. self) to init its m_hdrCustom

(5) The code is

void CustHeaderCtrl::init(CListCtrl * const pList)<br />
{<br />
    m_pParentList = pList;<br />
    CHeaderCtrl * pHeader = m_pParentList->GetHeaderCtrl();<br />
    ASSERT( SubclassWindow(pHeader->GetSafeHwnd()) );<br />
}<br />

(6) To catch clicks on the header items I made handlers for WM_NOTIFY messages resent to the header by it's parent list which where routed via WM_NOTIFY_REFLECT macro or alternatively via OnChildNotify.

:(Both work fine but only in debug code!
Who can give a solution? Thank you!

regards Werner

Re: Subclassed MFC CHeaderCtrl does only receive WM_NOTIFY in Debug

Rage21-Dec-05 1:14

Rage

21-Dec-05 1:14

WernerP wrote:
Both work fine but only in debug code!

Check what you have put in ASSERT macros, do not forget these are not compiled in Release mode.

~RaGE();

Re: Subclassed MFC CHeaderCtrl does only receive WM_NOTIFY in Debug

WernerP21-Dec-05 4:47

WernerP

21-Dec-05 4:47

Outrageous laughter (Ok, we think we can fix it).+
Thanks.

Bye, Werner

MFC functions fail when called from exported function in DLL

Mayank Ji20-Dec-05 23:32

Mayank Ji

20-Dec-05 23:32

I have made a regular dll in MFC. Here I have invoked an exported function in which I call a dialog using DoModal method. Now I added a static control on that dialog. Now, whenever I call that exported function in dll using an exe application i'm able to view that dialog, but the problem i'm facing is that i'm not able to get nor set data to the various controls(like static or edit) used in dialog. Like the MFC functions GetDlgItem, SetDlgItemText, SetWindowText, etc doesn't work.

Here is the piece of code

__declspec(dllexport) MyFun()
{
AFX_MANAGE_STATE(AfxGetStaticModuleState());
CMyDialog dlg;
dlg.DoModal();
}

//Constructor for CMyDialog
CDlgTest::CDlgTest(CWnd* pParent /*=NULL*/)
: CDialog(CDlgTest::IDD, pParent)
{

this->SetDlgItemText(IDC_STATIC, "Mayank"); //Not working
}

Re: MFC functions fail when called from exported function in DLL

krmed21-Dec-05 2:01

krmed

21-Dec-05 2:01

You can't use SetDlgItemText in the constructor because the window (IDC_STATIC) has not yet been created.

You need to override the OnInitDialog (WM_INITDIALOG) and put your SetDlgItemText in that function, after the call to CDialog::OnInitDialog();

Hope that helps.

Karl - WK5M
PP-ASEL-IA (N43CS)
<kmedcalf@ev1.net>
PGP Key: 0xDB02E193
PGP Key Fingerprint: 8F06 5A2E 2735 892B 821C 871A 0411 94EA DB02 E193

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