Instance of a class..... - C / C++ / MFC Discussion Boards

Re: Converting Hex number to Dec number

Mircea Puiu10-Dec-04 0:24

Mircea Puiu

10-Dec-04 0:24

You get exactly the same, as hex and dec (and other more) are different representations of the same number!

SkyWalker

Could anyone help me to comment these code in detail?

LiYS9-Dec-04 21:32

LiYS

9-Dec-04 21:32

/*I copy these code from Charles Petzold's Programming Windows. The functions in the WM_PAINT Message confused me a lot. Is there anyboday kindly enough to add comments to these function in details, thank you!
*/
#include <windows.h>

#define ID_TIMER 1

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT ("DigClock") ;
HWND hwnd ;
MSG msg ;
WNDCLASS wndclass ;

wndclass.style = CS_HREDRAW | CS_VREDRAW ;
wndclass.lpfnWndProc = WndProc ;
wndclass.cbClsExtra = 0 ;
wndclass.cbWndExtra = 0 ;
wndclass.hInstance = hInstance ;
wndclass.hIcon = LoadIcon (NULL, IDI_APPLICATION) ;
wndclass.hCursor = LoadCursor (NULL, IDC_ARROW) ;
wndclass.hbrBackground = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
wndclass.lpszMenuName = NULL ;
wndclass.lpszClassName = szAppName ;

if (!RegisterClass (&wndclass))
{

MessageBox (NULL, TEXT ("Program requires Windows NT!"),
szAppName, MB_ICONERROR) ;
return 0 ;
}

hwnd = CreateWindow (szAppName, TEXT ("Digital Clock"),
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, CW_USEDEFAULT,
CW_USEDEFAULT, CW_USEDEFAULT,
NULL, NULL, hInstance, NULL) ;

ShowWindow (hwnd, iCmdShow) ;
UpdateWindow (hwnd) ;

while (GetMessage (&msg, NULL, 0, 0))
{
TranslateMessage (&msg) ;
DispatchMessage (&msg) ;
}
return msg.wParam ;
}

void DisplayDigit (HDC hdc, int iNumber)
{
static BOOL fSevenSegment [10][7] = {
1, 1, 1, 0, 1, 1, 1, // 0
0, 0, 1, 0, 0, 1, 0, // 1
1, 0, 1, 1, 1, 0, 1, // 2
1, 0, 1, 1, 0, 1, 1, // 3
0, 1, 1, 1, 0, 1, 0, // 4
1, 1, 0, 1, 0, 1, 1, // 5
1, 1, 0, 1, 1, 1, 1, // 6
1, 0, 1, 0, 0, 1, 0, // 7
1, 1, 1, 1, 1, 1, 1, // 8
1, 1, 1, 1, 0, 1, 1 } ; // 9

static POINT ptSegment [7][6] = {
7, 6, 11, 2, 31, 2, 35, 6, 31, 10, 11, 10,
6, 7, 10, 11, 10, 31, 6, 35, 2, 31, 2, 11,
36, 7, 40, 11, 40, 31, 36, 35, 32, 31, 32, 11,
7, 36, 11, 32, 31, 32, 35, 36, 31, 40, 11, 40,
6, 37, 10, 41, 10, 61, 6, 65, 2, 61, 2, 41,
36, 37, 40, 41, 40, 61, 36, 65, 32, 61, 32, 41,
7, 66, 11, 62, 31, 62, 35, 66, 31, 70, 11, 70 } ;

int iSeg ;

for (iSeg = 0 ; iSeg < 7 ; iSeg++)
if (fSevenSegment [iNumber][iSeg])
Polygon (hdc, ptSegment [iSeg], 6) ;
}

void DisplayTwoDigits (HDC hdc, int iNumber, BOOL fSuppress)
{
if (!fSuppress || (iNumber / 10 != 0))
DisplayDigit (hdc, iNumber / 10) ;
OffsetWindowOrgEx (hdc, -42, 0, NULL) ;
DisplayDigit (hdc, iNumber % 10) ;
OffsetWindowOrgEx (hdc, -42, 0, NULL) ;
}

void DisplayColon (HDC hdc)
{
POINT ptColon [2][4] = { 2, 21, 6, 17, 10, 21, 6, 25,
2, 51, 6, 47, 10, 51, 6, 55 } ;

Polygon (hdc, ptColon [0], 4) ;
Polygon (hdc, ptColon [1], 4) ;

OffsetWindowOrgEx (hdc, -12, 0, NULL) ;
}

void DisplayTime (HDC hdc, BOOL f24Hour, BOOL fSuppress)
{
SYSTEMTIME st ;

GetLocalTime (&st) ;

if (f24Hour)
DisplayTwoDigits (hdc, st.wHour, fSuppress) ;
else
DisplayTwoDigits (hdc, (st.wHour %= 12) ? st.wHour : 12, fSuppress) ;

DisplayColon (hdc) ;
DisplayTwoDigits (hdc, st.wMinute, FALSE) ;
DisplayColon (hdc) ;
DisplayTwoDigits (hdc, st.wSecond, FALSE) ;
}

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static BOOL f24Hour, fSuppress ;
static HBRUSH hBrushRed ;
static int cxClient, cyClient ;
HDC hdc ;
PAINTSTRUCT ps ;
TCHAR szBuffer [2] ;

switch (message)
{
case WM_CREATE:
hBrushRed = CreateSolidBrush (RGB (255, 0, 0)) ;
SetTimer (hwnd, ID_TIMER, 1000, NULL) ;

// fall through

case WM_SETTINGCHANGE:
GetLocaleInfo (LOCALE_USER_DEFAULT, LOCALE_ITIME, szBuffer, 2) ;
f24Hour = (szBuffer[0] == '1') ;

GetLocaleInfo (LOCALE_USER_DEFAULT, LOCALE_ITLZERO, szBuffer, 2) ;
fSuppress = (szBuffer[0] == '0') ;

InvalidateRect (hwnd, NULL, TRUE) ;
return 0 ;

case WM_SIZE:
cxClient = LOWORD (lParam) ;
cyClient = HIWORD (lParam) ;
return 0 ;

case WM_TIMER:
InvalidateRect (hwnd, NULL, TRUE) ;
return 0 ;

case WM_PAINT:
hdc = BeginPaint (hwnd, &ps) ;

SetMapMode (hdc, MM_ANISOTROPIC) ;
SetWindowExtEx (hdc, 276, 72, NULL) ;
SetViewportExtEx (hdc, cxClient, cyClient, NULL) ;

SetWindowOrgEx (hdc, 138, 36, NULL) ;
SetViewportOrgEx (hdc, cxClient / 2, cyClient / 2, NULL) ;
SelectObject (hdc, GetStockObject (NULL_PEN)) ;
SelectObject (hdc, hBrushRed) ;

DisplayTime (hdc, f24Hour, fSuppress) ;

EndPaint (hwnd, &ps) ;
return 0 ;

case WM_DESTROY:
KillTimer (hwnd, ID_TIMER) ;
DeleteObject (hBrushRed) ;
PostQuitMessage (0) ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}

Re: Could anyone help me to comment these code in detail?

ThatsAlok9-Dec-04 22:12

ThatsAlok

9-Dec-04 22:12

case WM_PAINT:

	hdc = BeginPaint (hwnd, &ps) ;
	// i have removed though thing for beginner from here
	
	SelectObject (hdc, GetStockObject (NULL_PEN)) ;
	//simple it has selected the Red Brush for
	//to display digit
	SelectObject (hdc, hBrushRed) ;
	//Displaying time
	DisplayTime (hdc, f24Hour, fSuppress) ;
	
	EndPaint (hwnd, &ps) ;
return 0 ;

-----------------------------
"I Think this Will Help"
-----------------------------
Alok Gupta
visit me at http://www.thisisalok.tk

Re: Could anyone help me to comment these code in detail?

LiYS9-Dec-04 22:15

LiYS

9-Dec-04 22:15

/*What I mean is the following code, could you explain that in deepth?thanks!*/

SetMapMode (hdc, MM_ANISOTROPIC) ;
SetWindowExtEx (hdc, 276, 72, NULL) ;
SetViewportExtEx (hdc, cxClient, cyClient, NULL) ;

SetWindowOrgEx (hdc, 138, 36, NULL) ;
SetViewportOrgEx (hdc, cxClient / 2, cyClient / 2, NULL) ;

Re: Could anyone help me to comment these code in detail?

Mircea Puiu10-Dec-04 0:29

Mircea Puiu

10-Dec-04 0:29

Have a look at:
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/gdi/metafile_0lwy.asp[^]

SkyWalker

Problem about Owner Window

Arcrest9-Dec-04 21:21

Arcrest

9-Dec-04 21:21

Hi, everyone.
in my dialog-based application, i want to create a dialog (CMyDialog) that is not owned by the main dialog. i derive a class named CMyThread from CWinThread and create an instance of CMyDialog(modaless dialog) in the InitInstance because i want an instance of CMyDialog has its own message loop, so i create instances of CMyDialog use this function:
CreateMyDialog()
{
AfxBeginThread(RUNTIME_CLASS(CMyThread));
}

if i call CreateMyDialog before the creation of main dialog ,then the dialog will not be owned by main dialog, of course, Smile | :)

. but if i call CreateMyDialog after the main dialog has been created, the dialog will be an owned window.

so how to create an instance of CMyDialog without an owner window after the main dialog has been created.

Thanks.

Forward key to another controller

Mathias S.9-Dec-04 21:11

Mathias S.

9-Dec-04 21:11

In a dialog I got a CEdit and a ListCtrl. And when I press any A-Z key in the ListCtrl I want that key to be forwarded to the edit controller and focus to be change so that continues writing will be in the CEdit.

The solution I came up with is this. It appears to work.
But I get a bad felling about this solution. Anyone know if this is a correct way of doing this

// m_pEdit is a pointer to the CEdit.
void CMyListCtrl::OnChar(UINT nChar, UINT nRepCnt, UINT nFlags)
{
	if( nChar >= 'a'&& nChar <= 'z' || nChar >= 'A'&& nChar <= 'Z')
	{
		m_pEdit->PostMessage( WM_CHAR , (WCHAR)nChar,MAKELPARAM(nRepCnt,nFlags) );
		m_pEdit->SetFocus();
		return;
	}
	CListCtrl::OnChar(nChar, nRepCnt, nFlags);
}

Or should I do this from OnKeyDown instead?

/Mathias S.

Instance of a class.....

aaadetos9-Dec-04 20:44

aaadetos

9-Dec-04 20:44

I have a problem with an instance of a class. The class member variable instantiated by a class object appears not to be updated to what the user defines at run time.

The problem is to do with the fact that the user-defined variable at run-time is not being used. How do I change that. UpdateData(TRUE); in the change or update events of those variables don't work.

For instance,

<br />
double x = 0;//this is already initialized in the compiler-generated constructor <br />
<br />
CKuchukDlg MyClass;<br />
MyClass.m_dWellRad = x;<br />

At run-time, the proigram crashes. On debugging, I found that the compiler isn't using the value ascribed by the user(me) as x. After using x=0, x later becomes some bogus number: -9.2559631349318e+061. When i don't initialize my variable x, i get a warning; but still at run-time, x becomes this bogus number again, not the value set at run-time.

How can i capture the value set at run-time??

<br />
void CKuchukDlg::OnUpdateWellrad() <br />
UpdateData(TRUE);<br />

doesn't help. Neither does it help on the event-->void CKuchukDlg::OnChangeWellrad()

How to get WM_VSCROLL?

freehawk9-Dec-04 20:27

freehawk

9-Dec-04 20:27

Hello everyone

I have a window with two scrolls, and I want to get WM_VSCROLL in function "PreTranslateMessage(MSG* pMsg) ". Though I add "case WM_VSCROLL:" to soource code, but I can not get it. Because the message does not come into "PreTranslateMessage(MSG* pMsg)". How to get it?

Thanks.

-Freehawk

Re: How to get WM_VSCROLL?

ThatsAlok9-Dec-04 21:46

ThatsAlok

9-Dec-04 21:46

Overide WM_VSCROLL message in your Window
if you are using the MFC
the Function Declaration is like this

OnHScroll(UINT nSBCode,UINT nPos,CScrollBar *pScrollBar)

where pScrollbar contain pointer to that Scrollbar if it is not Window Default Scrollbar.

In Win32
lParam contain the pointer to The Scrollbar you have to typecast that.

-----------------------------
"I Think this Will Help"
-----------------------------
Alok Gupta
visit me at http://www.thisisalok.tk

Re: How to get WM_VSCROLL?

freehawk9-Dec-04 22:00

freehawk

9-Dec-04 22:00

In fact I want to handle something before WM_VSCROLL happens. I dont know how to catch.

-Freehawk

Re: How to get WM_VSCROLL?

ThatsAlok9-Dec-04 23:54

ThatsAlok

9-Dec-04 23:54

Are you using switch case like this

switch(LOWORD(pMsg->message))

or using some other method

-----------------------------
"I Think this Will Help"
-----------------------------
Alok Gupta
visit me at http://www.thisisalok.tk

Re: How to get WM_VSCROLL?

Mircea Puiu10-Dec-04 0:35

Mircea Puiu

10-Dec-04 0:35

Normally you write your code inside OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar);

Should you still want to intercept the WM_SCROLL message, then use the PreTranslateMessage() function of your app class (not the dlg one)

SkyWalker

Point to CView from CWinApp

johnny__XP9-Dec-04 19:54

johnny__XP

9-Dec-04 19:54

Is there any way to get a pointer from CWinApp to CView or generally to access CView public members and methods from within CWinApp?
Thanks.

how to access CEditView for Doc

josephvan9-Dec-04 18:43

josephvan

9-Dec-04 18:43

i program an MDI text editor, the MFC template consist of a ****Doc derived from CDocument and a ****View derived from CEditView class, but i have problem when save the text i entered, i wanna use the serialize() function in the ****Doc, i've intended to get a pointer to the CEditView and get the chars in CEditView then to save it by ar<

About Mapping Mode

LiYS9-Dec-04 17:58

LiYS

9-Dec-04 17:58

Hi all:
Just these days I've been bothering by the Windows Mapping Mode a lot. I'm using the Charles Petzold's Programming Windows and when I see the chapter about GDI Mapping Mode I can't really understand what it is all about. Maybe some other materials will help.
Does anyone has any reference material about Mapping Mode?Or give me a little explanation! Smile | :)

mdi

vc-programmer-9-Dec-04 17:46

vc-programmer-

9-Dec-04 17:46

when mdi application run,child window is default miximize size window.
how i can do???

Re: mdi

Renjith Ramachandran9-Dec-04 19:10

Renjith Ramachandran

9-Dec-04 19:10

BOOL maximized;
CMDIChildWnd* child = MDIGetActive(&maximized);
if (child && (maximized || child->IsIconic()))
child->MDIRestore();

Ninety-eight percent of the thrill comes from knowing that the thing you designed works, and works almost the way you expected it would. If that happens, part of you is in that machine.

std::map and string as a key

Imtiaz Murtaza9-Dec-04 17:13

Imtiaz Murtaza

9-Dec-04 17:13

Dear friends,

I am using std::map. I want to give std::string as a key. But whenever i am giving std::string as a key, compiler starts giving horrible errors. I checked both in VC 6.0 and VC 7.0. Here is the program:

#include <iostream>
#include <map>

using std::string;

int main(int argc, char* argv[])
{
typedef std::map<string, string> DICTIONARY;

DICTIONARY m_dictionary;

std::pair< DICTIONARY::iterator, bool > result;

result = m_dictionary.insert(DICTIONARY::value_type("Sincere", "Honest"));

return 0;
}

One of the errors i am getting is:

(139): error C2784: 'bool std::operator <(const std::_Tree<_Traits> &,const std::_Tree<_Traits> &)' : could not deduce template argument for 'const std::_Tree<_Traits> &' from 'const std::string'

Imtiaz

Re: std::map and string as a key

Joaquín M López Muñoz9-Dec-04 19:59

Joaquín M López Muñoz

9-Dec-04 19:59

You forgot to add the following:

#include <string>

After adding this #include, you still will get many C4786 warnings: these warnings are entirely harmless and can be supressed with

#pragma warning(disable:4786) // add this to the very beginning of your program

These two changes will get you a clean compile. Best,

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo
Want a Boost forum in Code Project? Vote here[^]!

How do I stop appearing SQL Sever Login Dialog again and again?

pubududilena9-Dec-04 17:13

pubududilena

9-Dec-04 17:13

hi all,
I connected with SQL Sever database using C++.I have used ODBC Connection.I added a class which based class is CRecordset..
The problem is when I open the Application it always displaying the "SQL Server Login" Dialog and ask the username and password.

How do I stop appearing that Login Dialog when I openning it?
please any one know this.please help me..

Re: How do I stop appearing SQL Sever Login Dialog again and again?

Renjith Ramachandran9-Dec-04 18:48

Renjith Ramachandran

9-Dec-04 18:48

use CDatabase::noOdbcDialog as the second parameter in OpenEx() method.

Eg; extern CDatabase oDb;
extern CString csConnection;

oDb.OpenEx(csConnection, CDatabase::noOdbcDialog );

this will suppress the login dialog.

Ninety-eight percent of the thrill comes from knowing that the thing you designed works, and works almost the way you expected it would. If that happens, part of you is in that machine.

Help!

Anonymous9-Dec-04 13:09

Anonymous

9-Dec-04 13:09

¿Eres programador en C++? ¡Esto te interesa! ¡Unete a nuestro grupo!

Click to join cpp_en_espanol

Re: Help!

toxcct9-Dec-04 21:54

toxcct

9-Dec-04 21:54

pero aqui, hablamos ingles...

so speak english with use, or stay into you grupo

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

How to do oldschool graphics in win

mirex9-Dec-04 11:03

mirex

9-Dec-04 11:03

Hi guys, Im working on an old-skool project which should be game in 0x13 Dos resolution which was 320 x 200, 256 colours, paletized. Can anyone tell me how it is possible to use this mode in windows (in VC++)?

Initializing was done easily and probably will be no problem, but drawing in this mode was done through direct memory access to 0xA000:0000 which will windows probably block in win app.

Or, is there any other way how to use paletized colour mode like this ? thanks

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