CHeaderCtrl - C / C++ / MFC Discussion Boards

Harold Bamford7-Feb-03 6:18

7-Feb-03 6:18

georgiek50 wrote:
Even though it is an array of byte wouldn't \0 take care of everything? which brings me to ask another question. If I declared an array of bytes say array[100] but then only needed to fill the first fifty. Do I need a NULL character like in a string? If yes how would I set it. If no, why not?

I didn't make myself clear. If you are using the array of bytes as a null-terminated cstring:

strcpy(r1,"This is a string");

Then terminating at the "zero'th" position will clear out the string. For example, if you said:

strcpy(r1,"0123456789 This is a string");
r1[15] = 0;
printf("%s\n", r1);

The output would be "0123456789 This"

If you then dumped the first 20 bytes of r1:

for(int i = 0; i < 20; i++)
{
   printf("0x%02X ", r1[i]);
}

You would get something like:

0x30 0x31 0x32 ... 0x39 0x20 0x54 0x68 0x69 0x73 0x00 0x69 0x73 ...

That's the convention for null-terminated cstrings (not to be confused with CString); a 0 terminates the string. If it is just an array of bytes, then 0 is just another value.

Re: Easy question:

georgiek507-Feb-03 7:38

georgiek50

7-Feb-03 7:38

Ok, I see what you're saying now.

bitmaps in statusbar

Crash Operator6-Feb-03 13:20

Crash Operator

6-Feb-03 13:20

Is there an easy way to put a bitmap in the status bar?

I've been looking into it...and my solution is to derive a class from CStatusBar and then add bitmap functionality manually.

I would think there is an easier way to do this.

john

Re: bitmaps in statusbar

-Dy6-Feb-03 23:04

-Dy

6-Feb-03 23:04

Crash Operator wrote:
my solution is to derive a class from CStatusBar

Yeah, and then override virtual void DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct);

Check out the MSDN article Q149407 (HOWTO: How to Display a Bitmap in a CStatusBar Pane)

Hope it helps!

Dylan
Boycott Bush
Punch GWB

Not to Get Black background image

mkashifkkj6-Feb-03 13:06

mkashifkkj

6-Feb-03 13:06

I am using the following code to get the image drawn on a hidden window.

CBitmap bitmap;
CDC memDC;

memDC.CreateCompatibleDC(NULL);

bitmap.CreateCompatibleBitmap(&memDC, 600,400);

CBitmap* pOldBitmap = memDC.SelectObject(&bitmap);

memDC.Rectangle (100,100,300,300);
memDC.Ellipse (100,100,400,400);

memDC.BitBlt(0, 0, 600,400,NULL, 0, 0, SRCCOPY);

and then saving this image as a bitmap file.

But passing NULL in BitBlt (bcz i want to draw images in hidden window) i get the background color of my
image as black.

How to change bgcolor to white.

avaoiding flicker on CUSTOMDRAW

User 98856-Feb-03 12:39

User 9885

6-Feb-03 12:39

I have a list control that uses LVS_OWNERDATA and uses custom draw. When I do a SetItemCountEx to redraw the window, the list erases and repaints causing flicker. Is there any standard way to handle this flicker OR do I have to handle EraseBackgound and do some logic there to erase only the area without items. I will have to paint the background where there are no items.

All this looks like workarounds to me, and I think I am missing something very obvious.

Thomas

My article on a reference-counted smart pointer that supports polymorphic objects and raw pointers

modified 29-Aug-18 21:01pm.

Re: avaoiding flicker on CUSTOMDRAW

Moak7-Feb-03 1:09

Moak

7-Feb-03 1:09

Hi, many classes use a memory DC to avoid flickering,
here is a link that describes different tactics (e.g. WS_CLIPCHILDREN does a good work):

http://freespace.virgin.net/james.brown7/tutorials/flicker.htm

CHeaderCtrl

User 98856-Feb-03 12:30

User 9885

6-Feb-03 12:30

I want the list control header to look flat (like with the LVS_NOSORTHEADER), but I want the OnColumnClick notification. Is there a standard way to do it? Or do I have to subclass and implement drawitem?

I would prefer to have the header control drawn using the default code (I do not want to get involved in the font sizing with different dpi screens and such other details), so, if I subclass the header, can I fire the LVN_COLUMNCLICK myself?

My article on a reference-counted smart pointer that supports polymorphic objects and raw pointers

modified 29-Aug-18 21:01pm.

Re: CHeaderCtrl

OBRon7-Feb-03 4:17

OBRon

7-Feb-03 4:17

I think you can trap for left mouse clicks on your list control and then do a hit test on the header control. Then you could launch your sort function within the mouse click rather than the looking for the OnColumnClick notification. Like the following:

CHeaderCtrl* header = m_ListCtrl.GetHeaderCtrl();
if (header)
{
CPoint headerPoint = point;
LV_HITTESTINFO hitTestInfo;

header->ScreenToClient(&headerPoint);

hitTestInfo.pt = headerPoint;
::SendMessage(header->m_hWnd, HDM_HITTEST, 0, (LONG)(HD_HITTESTINFO FAR*)(&hitTestInfo));

if (hitTestInfo.iItem >= 0) // User hit a header column
{
// Do sort routine here
}
}

Ron Ward

Re: CHeaderCtrl

User 98857-Feb-03 4:31

User 9885

7-Feb-03 4:31

That is indeed a great suggestion.
So simple that, I ask myself why did I not think of that?
Big Grin | :-D

Thank you so much Rose | [Rose]

My article on a reference-counted smart pointer that supports polymorphic objects and raw pointers

modified 29-Aug-18 21:01pm.

Coding database !

Hadi Rezaee6-Feb-03 11:50

Hadi Rezaee

6-Feb-03 11:50

Hello,
What's the best way to coding database ?

My month article: Game programming by DirectX by Lan Mader.
Please visit in: www.geocities.com/hadi_rezaie/index.html

Hadi Rezaie

Re: Coding database !

Anonymous6-Feb-03 11:57

Anonymous

6-Feb-03 11:57

I use VS to edit scripts, but sometimes I write SQL in Notepad.

Re: Coding database !

Hadi Rezaee6-Feb-03 12:21

Hadi Rezaee

6-Feb-03 12:21

Sorry,
I think i've asked the question very bad, in fact i've already database (it's access 2000) ...

I wanna know what's best way to encrypt the data in the database ?
and then use of encrypted data in my program.

Regards,

My month article: Game programming by DirectX by Lan Mader.
Please visit in: www.geocities.com/hadi_rezaie/index.html

Hadi Rezaie

Re: Coding database !

Willem B7-Feb-03 2:18

Willem B

7-Feb-03 2:18

Hadi Rezaee wrote:
best way to encrypt the data in the database

if i would do something like that, i would do something like this:

use the class that is explained here: http://www.codeproject.com/cpp/aes.asp[^]
Every record that is written to de database is first encrypted bij the class.

Hadi Rezaee wrote:
in fact i've already database

for this problem i would put a character at place 1 in your record that says if the record is encrypted yet, if the character is not there the program will know that the record is not encrypted. then ofcourse encrypt the data and put the character before the encrypted data.

this is the way that i would do something like that, i don't know if its the best way.

[]D [] []D []

Get Network namnes and there IP ?

Larsson6-Feb-03 11:36

Larsson

6-Feb-03 11:36

How can I get the the network names and there IP adresses?

\Larsson

Re: Get Network namnes and there IP ?

palbano6-Feb-03 15:20

palbano

6-Feb-03 15:20

Use WNetOpenEnum to obtain the names...
then for each name use gethostbyname to resolve the IP.

Hope this helps

"No matter where you go, there your are..." - Buckaoo Banzi
<pete/>

Re: Get Network namnes and there IP ?

Larsson12-Feb-03 5:48

Larsson

12-Feb-03 5:48

Well,
I don't get it to work can you please send me some
code sample?

\Larsson

GDI+ and DirectX/direct video output

Roman Nurik6-Feb-03 11:04

Roman Nurik

6-Feb-03 11:04

im making a game that is rendered by GDI+

however, standard GDI BitBlt's and even threads make the game window look very slow and i can see the refresh rate or whatever you call it when i render to the HDC

my question is... is it possible (and is there an example) of using GDI+ to render to a DirectDraw surface (ill probably use the latest DirectDraw or whatever is easier)

OR (even better)

is there a way for me to draw directly to the screen (without windows layer) like Windows Media Player and DirectX seem to do?

i know it would require some pixel-format conversions but i'm ready to work with that

any suggestions?

- Roman -

__ftol2 ?? where did it come from? .NET?

Jared Allen6-Feb-03 10:24

Jared Allen

6-Feb-03 10:24

Ok i just got the windows media DRM SDK delivered to me from MS. I added it into my project and now i get a linker error.

error LNK2001: unresolved external symbol __ftol2

I also updated my MS Platform SDK a few dats ago (while i was trying to get a copy of the internet SDK , i didn't even want the upgrade)

I've searched and heard that __ftol2 may have something to do with managed C++ and or .NET , can anyone tell me how to get around this.

thanks.

Jared Allen.
www.chironexsoftware.com

Re: __ftol2 ?? where did it come from? .NET?

Joaquín M López Muñoz6-Feb-03 10:37

Joaquín M López Muñoz

6-Feb-03 10:37

Seems like the library you're trying to use is targeted at VC++ 7.0: a search on Usenet reveals that __ftol is an internal library of VC++ 7.0's C run-time library.

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

Re: __ftol2 ?? where did it come from? .NET?

C^hris L^osinger6-Feb-03 10:50

C^hris L^osinger

6-Feb-03 10:50

_ftol is a function invoked when you do a double to long typecast. it's inserted automatically by the compiler:

; 38   : 
; 39   :    double t = 100.23;

	mov	DWORD PTR _t$[ebp], 1374389535		; 51eb851fH
	mov	DWORD PTR _t$[ebp+4], 1079578296	; 40590eb8H

; 40   :    int l = t;

	fld	QWORD PTR _t$[ebp]
	call	__ftol
	mov	DWORD PTR _l$[ebp], eax

i'm not sure what _ftol2 is about, but i suspect it's a .Net thing. i see it when i accidentally try to mix VC6 and VC7 .obj files.

-c

Get there first with something patented, proprietary, and broken, then send lawyers after anyone who points out problems. --- Peter Gutmann

Fractals

Re: __ftol2 ?? where did it come from? .NET?

Jared Allen6-Feb-03 11:51

Jared Allen

6-Feb-03 11:51

Any idea how to get around it without using VC++ 7.0 ?

The problem is I have a .lib file that references it, and i don't have the source. It's from MS

I've tried to define the function __ftol

long __ftol2(float x) {
return (long)x;
}

But i still get the link problem, i think i'm putting it in the wrong place? put i should be able to have it in any .cpp file of the project?

Jared Allen.
www.chironexsoftware.com

Re: __ftol2 ?? where did it come from? .NET?

C^hris L^osinger6-Feb-03 12:20

C^hris L^osinger

6-Feb-03 12:20

sorry , i don't know. i always fix it with a rebuild-all, but since i'm not using any libs that i don't have the source to, there's no problem once everything is rebuilt with the same compiler.

-c

Get there first with something patented, proprietary, and broken, then send lawyers after anyone who points out problems. --- Peter Gutmann

Fractals

createThread , Prototype, and extren call correctness?

Pecan2046-Feb-03 7:42

Pecan204

6-Feb-03 7:42

My last attempt at launching a fortran dll with
createThread resulted in the following error.

error LNK2001: unresolved external symbol "unsigned long
__stdcall FTREND3(void *)" (?FTREND3@@YGKPAX@Z)
Debug/cinterface3.exe : fatal error LNK1120: 1 unresolved
externals

I am not sure if the extern and DWORD prototypes are
correct? If I comment out the DWORD function prototype it
compiles and links but does not start the integer function.

Does the createThread actually pass the integer argument of 1 or just start the function and then it sees the shared memory?

Can someone comment? Thanks.

Code below:
#include <stdio.h>
#include <string.h>
#include <windows.h>

struct io {
char time[10];
int start;
};
struct io cio;

/* prototype for function */
DWORD WINAPI FTREND3(LPVOID);
//DWORD WINAPI FTREND3(LPVOID pvoid);

//extern "C" long _stdcall FTREND3 ( long );
// declspec(dllimport) for DLL's
extern "C" __declspec(dllimport) long _stdcall FTREND3 (
long );

void main (void)
{
DWORD tid;
HANDLE hThread;
cio.start = 1;

hThread = CreateThread(NULL, 0, (LPTHREAD_START_ROUTINE)
FTREND3, &cio, 0, &tid);
CloseHandle(hThread);

printf("In c after fortran thread started\n\n");
printf("string = %s\n",cio.time);
}

INTEGER FUNCTION FTREND3 (TIO)
USE DFPORT
IMPLICIT NONE
!DEC$ ATTRIBUTES DLLEXPORT :: FTREND3
TYPE IO
INTEGER START ! if 1 start timer
CHARACTER*10 timeIs
END TYPE IO

TYPE(io):: tio
DO WHILE ( tio%START .EQ. 1)
tio%timeIs = CLOCK ( ) ! Uses DFPORT
tio%timeIs = tio%timeIs // char(0)
write (6,*) 'In fortran after time call'
write (6,*) ' Time = ', tio%timeIs
FTREND3 = 1
ENDDO
FTREND3 = 0
RETURN
END FUNCTION FTREND3

Re: createThread , Prototype, and extren call correctness?

Joaquín M López Muñoz6-Feb-03 9:13

Joaquín M López Muñoz

6-Feb-03 9:13

DWORD WINAPI FTREND3(LPVOID);
extern "C" __declspec(dllimport) long _stdcall FTREND3 ( long );

These two lines shouldn't coexist. Both are function prototypes. Remove the first.
As for the second problem, main is exiting right after the thread has been launched, i.e. it without waiting for it to complete. Try replacing

CloseHandle(hThread);

for

CloseHandle(hThread);
WaitForSingleObect(hThread,INFIINTE);

Last point is not a question of yours but of mine Smile | :)

What do you want to create a thread to call FTREND3? You sure you cannot simply call it as a regular C function?

Joaquín M López Muñoz
Telefónica, Investigación y Desarrollo

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