C / C++ / MFC

18-Sep-07 8:11

How would I go about using a windows style of WS_EX_COMPOSITED with an MFC View window? (I don't want to know about other methods of double buffering, just how to set this style.)

Thanks!

Smile | :)

Mark Salsbery18-Sep-07 8:49

Mark Salsbery

18-Sep-07 8:49

I would recommend reading the docs for CreateWindowEx() -
specifically anything there related to WS_EX_COMPOSITED.

To use the style in MFC, specify the WS_EX_COMPOSITED extended style
when calling CreateEx() to create a window.

This style can also be set in a window class' PreCreateWindow() override.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Californian218-Sep-07 9:25

18-Sep-07 9:25

Hi,

Thanks. Actually, I have already read up on that, and have no problem with WS_EX_COMPOSITED when not using MFC. However, I am not seeing the expected results when I use WS_EX_COMPOSITED with MFC. I am overriding the PreCreateWindow method for a View in a MDI Doc/View application:

BOOL CMyProgView::PreCreateWindow(CREATESTRUCT& cs)
{
cs.dwExStyle &= WS_EX_COMPOSITED;

return CScrollView::PreCreateWindow(cs);
}

but I still get flickering when I draw the window by overriding the OnDraw method. In OnDraw, I'm using a GDI+ Graphics object, and I use the Graphics::Clear method before doing my drawing. There is no flickering when NOT using MFC, even using Graphics::Clear, if the WS_EX_COMPOSITED window style is used.

I thought maybe MFC was using some conflicting window styles, but don't know. Just wondered if something more was required, such as changing some other window style(s) to be compatible with WS_EX_COMPOSITED, or something like that.

Thanks again.

Confused | :confused:

Mark Salsbery18-Sep-07 9:38

Mark Salsbery

18-Sep-07 9:38

Californian2 wrote:
cs.dwExStyle &= WS_EX_COMPOSITED;

Maybe try

cs.dwExStyle |= WS_EX_COMPOSITED;

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Californian218-Sep-07 10:03

18-Sep-07 10:03

Oops.

Nevertheless,

cs.dwExStyle |= WS_EX_COMPOSITED;

does not work. There does seem to be some window style conflict.

Re: WS_EX_COMPOSITED [modified]

Mark Salsbery18-Sep-07 10:19

Mark Salsbery

18-Sep-07 10:19

Hmmm that should work.

Maybe try forcing styles identical to your non-MFC version by calling
the base class PreCreateWindow() FIRST, then overwrite the style and exstyle
with your values, something like:

BOOL CMyProgView::PreCreateWindow(CREATESTRUCT& cs)
{
   if (CScrollView::PreCreateWindow(cs))
   {
      cs.style <font color="Red">=</font> WS_CHILD;
      cs.dwExStyle <font color="Red">=</font> WS_EX_COMPOSITED;
      return TRUE;
   }

   return FALSE;
}

How are you forcing it to draw so you see flicker? During resizing? With a timer?

If that doesn't work, note that the default CScrollView window class style has CS_HREDRAW | CS_VREDRAW
set...I don't know if that effects this at all.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Californian219-Sep-07 6:06

19-Sep-07 6:06

Hi,

Sorry to take so long to get back on this. The problem does indeed seem to be related to scrolling. Mostly I have problems with Graphics::DrawImage with large bitmaps. Everything is fine (except for flickering when resizing by dragging the lower right corner of the window, and some other times), until I add cs.dwExStyle |= WS_EX_COMPOSITED in a PreCreateWindow override. Then, my image flickers and sometimes completely disappears when it is scrolled. It comes back if the window is resized, but is lost again when the window is scrolled.

I'm not having much luck overriding the base class PreCreateWindow with other styles, but I'll double check whether I'm doing that correctly.

Thanks for any help you can give.

OMG | :OMG:

-- modified at 12:23 Wednesday 19th September, 2007

data types conversion

shpid3r18-Sep-07 7:56

18-Sep-07 7:56

Hello 2 everyone interested!
I am looking for a function to convert data from DWORD, float,double and SYSTEMTIME (if possible, this last one) into string.
In fact, I want to dump variables of those data types into a log file. I am using MFC, with CFile and <filename>.Write() function, which expects a string as a parameter.
If I try using filename.Write(LPWSTR(var))(LPCWSTR, or any other string types...) i get conversion errors (sometimes that it requires 'explicit cast').
Any ideas ?

DevMentor.org18-Sep-07 8:02

18-Sep-07 8:02

have you tired sprintf_s( )

---
Yours Truly, The One and Only!
devmentor.org
Design, Code, Test, Debug

shpid3r18-Sep-07 8:34

18-Sep-07 8:34

I have, now. It doesn`t work, although I include stdio.h. It accepts the header (I mean, it finds it to include it), but when encountering sprintf_s() in sais "undeclared identifier".

I have also tried _itoa_s()
Link provided: http://msdn2.microsoft.com/en-us/library/0we9x30h(VS.80).aspx
When compiling, it seems ok, but when the application comes to using that part of the code, I get an application error code, and Windows asking me to send the info to microsoft.

I think that perhaps because I try to convert an unsigned int (DWORD - 64-bit unsigned integer.), using an int-converting function, might result in some buffer overflows. Can anyone suggest an alternative to _itoa_s (for using with unsigned int vars)? I can`t figure it out which is the one...

I think I should mention that I`m writing code for a Smart Device (pocket pc) using WM5.

DevMentor.org18-Sep-07 8:43

18-Sep-07 8:43

sprintf_s will do the trick, I use it all the time... you are doing something wrong in the code?

can you try sprintf, maybe the api i provided earlier is not supported for smart device development?

---
Yours Truly, The One and Only!
devmentor.org
Design, Code, Test, Debug

shpid3r18-Sep-07 9:04

18-Sep-07 9:04

Routine Required header

sprintf_s, <stdio.h>
_sprintf_s_l

Compatibility

Windows 95, Windows 98, Windows 98 Second Edition, Windows Millennium Edition, Windows NT 4.0, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003

It seems that it doesn`t support Windows Mobile. Similar results for sprintf Frown | :(

back to _ui64toa_s, I get an error, stating that radix outside of 2;36.
The code is here:

char* buffer;
   //size_t sizeOfBuffer;
   int Radiux;
   _ui64toa_s(GPSData.dwSatellitesInView,buffer,65,Radiux);
   GPSLog.Write("Sats View:",15); GPSLog.Write(buffer,3);
   _ui64toa_s(GPSData.dwSatelliteCount,buffer,65,Radiux);
   GPSLog.Write("Sats Count:",15); GPSLog.Write(buffer,3);

where the 2 vars to be converted are DWORD.
Ideas ?

shpid3r18-Sep-07 9:11

18-Sep-07 9:11

update to this:
I have initialised Radiux with 5 (just... picked it) and it won`t get out with error.
But I get strange data, when logging i get squares instead of some characters, yet some numbers are displayed, too. Who can tell me what does Radiux do ? I don`t understand from the function's description, found here: http://msdn2.microsoft.com/en-us/library/0we9x30h(VS.80).aspx

DevMentor.org18-Sep-07 9:30

DWORD Solved. How about double and SYSTEMTIME [modified]

18-Sep-07 9:30

you have to set the radix value, which would be 10 for decimal.
try int Radiux = 10;

also try not to hard-code values...how is buffer defined? if it's defined like an array, and not alloacted on the heap you might want to change your ocde to something like this.

char buffer[100] = {0};
const int Radiux = 10;
...
_ui64toa_s( GPSData.dwSatellitesInView,
            buffer, 
            sizeof(buffer),
            Radiux );

(*)The "={0}" is a quick way to zero out the array Big Grin | :-D

(*) if you use const int, the compiler is smart enough to replace put in the value (in this case 10) everwhere the variable show up, so no actual storage is required for the Radiux Wink | ;)

I hope this helps!!!

---
Yours Truly, The One and Only!
devmentor.org
Design, Code, Test, Debug

shpid3r19-Sep-07 0:29

Re: DWORD Solved. How about double and SYSTEMTIME

19-Sep-07 0:29

Thanks a lot, for the code sample and especially for tips about hardcoding (though I've copy-pasted code provided on msdn2.microsoft.com Wink | ;)

!

Now... how about double to string and more important systemtime to double ?

DevMentor.org19-Sep-07 8:52

All Issues Solved. 10x for support

19-Sep-07 8:52

I am glad to hear you got something working!

But if you're using a fixed declared array like I showed you then it's better to use sizeof().

Also you can't use strlen on a zeroed out buffer, right? you will get a size of zero!!!

Moreover, you are reading data into the buffer, strlen is the wrong function to use, your code has a bug in it.

If you're using the buffer again, just make sure to zero it out before the call to _ui64toa_s( )

memset( buffer, 0 ,sizeof(buffer) );

---
Yours Truly, The One and Only!
devmentor.org
Design, Code, Test, Debug

shpid3r19-Sep-07 10:53

Using Emoticons(Smilies) in Rich Text Box

19-Sep-07 10:53

Well, I now did write sizeof(buffer) instead of fix size, and I understand the benefits, thanks to you.
I wonder how you found out about me using strlen, was just a trial (it wasn`t that obvious for me that was wrong before trying it), and I've modified the post when I`ve discovered that it doesn`t work. Indeed,learned on the hard way, strlen on a buffer is a No-No.
Thank's for the tip about zeroing the buffer before calling _ui64toa_s(). It does ring a bell, now., though in my application this part of the code comes to execution only when data exists in all fields I convert, so it's not posibile to have to convert an old value. Anyway, for future practice...

Concerning double to string, I used var-(int)var (where var was of type: double) to get the integer part (which was... int) and used _itoa_s to convert it into a string, and the rest I started multiplying by 10 (I only needed 4 digits after .) .

SYSTEMTIME is a structure type, in which all components are of type WORD. So perhaps _itoa_s() - or someone in it`s family - will do the trick.
Thanks again for all your help!
Best wishes!

---
One chance in a million is still a chance!

ddspliting18-Sep-07 7:23

ddspliting

18-Sep-07 7:23

hey all!
is RichText Box supports the emoticons like we ve got in Msn or Yahoo? if Yes thn wats the procedure to include them using codes? and wat about the source of that images?

Re: Using Emoticons(Smilies) in Rich Text Box

Nathan Holt at EMOM18-Sep-07 7:35

Nathan Holt at EMOM

18-Sep-07 7:35

ddspliting wrote:
is RichText Box supports the emoticons like we ve got in Msn or Yahoo? if Yes thn wats the procedure to include them using codes? and wat about the source of that images?

The only support I've heard about is that you can insert images in rich text. I've never done it myself, but I know you'll have to provide your own images.

Nathan

Convert Problem CString to double

Andy20218-Sep-07 7:03

Andy202

18-Sep-07 7:03

The value in the text box is "50.56556", but the converted value is 5.
Also the value of the temp string is "5"

CString sz_DisplayStr;<br />
char *temp;<br />
<br />
m_cInitLat.GetWindowTextW(g_szDisplayStr);<br />
short length = g_szDisplayStr.GetLength();<br />
temp = (char*)(LPCTSTR)g_szDisplayStr.GetBuffer(length);	<br />
m_dInitLat = atof(temp);

Also why has GetWindowText gone to GetWindowTextW?

Andy

Re: Convert Problem CString to double

C^hris L^osinger18-Sep-07 7:12

C^hris L^osinger

18-Sep-07 7:12

atof doesn't like wide characters. try _wtof

image processing toolkits | batch image processing

Re: Convert Problem CString to double

Maximilien18-Sep-07 7:13

Maximilien

18-Sep-07 7:13

Andy202 wrote:
m_dInitLat

What's the type of that ?

Maximilien Lincourt
Your Head A Splode - Strong Bad

Re: Convert Problem CString to double [modified]

DevMentor.org18-Sep-07 8:08