C / C++ / MFC Discussion Boards

Re: Transparent Window

CPallini29-Feb-08 1:51

CPallini

29-Feb-08 1:51

Try to reformulate the description of your problem since it isn't that clear.
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

Re: Transparent Window

Rajesh R Subramanian29-Feb-08 1:52

Rajesh R Subramanian

29-Feb-08 1:52

bhat wrote:
hey Tell me how to come out of this

It's like Hotel California. You can check out any time you like. But you can never leave.

*Rajesh starts playing his guitar, having a fun time fishing*

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Re: Transparent Window

Gary R. Wheeler1-Mar-08 3:48

Gary R. Wheeler

1-Mar-08 3:48

"On a dark desert highway, cool wind in my hair..."

Damn, I did have hair once.

Back when that album came out.

Software Zen: delete this;
Fold With Us![^]

Re: Transparent Window

Rajkumar R29-Feb-08 2:47

Rajkumar R

29-Feb-08 2:47

Did you coded for this,

May be WS_EX_TRANSPARENT style set to the window.
May be WM_ERASEBKGND and / or WM_PAINT handled but not doing anything or not passing to default window procedure.

Directshow filter crashes in thumbnail view

mTahir29-Feb-08 0:45

mTahir

29-Feb-08 0:45

Hi all,
I have created a Directshow filter for video playback. It runs fine in GraphEdit or by double clicking the video file but when I select the thumbnail view for the video file in explorer, explorer crashes giving the ASSERT error

Executable: explorer.exe Pid 328 Tid fc8. Module myFilter.ax, 5 objects left active! At line 317 of C:\DXSDK\Samples\C++\DirectShow\BaseClasses\dllentry.cpp
Continue? (Cancel to debug)

Can anybody suggest how this bug can be removed?

Thanks in Advance.

Regards,
Tahir

Re: Directshow filter crashes in thumbnail view

Cedric Moonen29-Feb-08 0:58

Cedric Moonen

29-Feb-08 0:58

Did you try to use your debugger ?

Cédric Moonen
Software developer

Charting control [v1.3 - Updated]

Re: Directshow filter crashes in thumbnail view

Rajkumar R29-Feb-08 2:07

Rajkumar R

29-Feb-08 2:07

mTahir wrote:
explorer.exe Pid 328 Tid fc8. Module myFilter.ax, 5 objects left active! At line 317 of

It occurs if you acquired any interface and not releasing it, when the filter is about to destruct. The interface acquired in your filter may be other filters which might acquired other interfaces and your assert message shows 5 interfaces not released.

I think you must be able to get this error in graphedit also, stress test for different scenarios, like pause the graph and close the graphedit, insert and remove filters, close graphedit while running graph. The thumbnail might be in different state which you never tried in graphedit.

log the reference count of the interfaces while you acquire and release and check whether it matches. for all your pins and filters override the
"STDMETHODIMP_(ULONG) NonDelegatingAddRef();"
"STDMETHODIMP_(ULONG) NonDelegatingRelease();" so that you can log easily.

Re: Directshow filter crashes in thumbnail view

mTahir2-Mar-08 20:03

mTahir

2-Mar-08 20:03

Raj thanks for your reply.

I will look into it. I will try 'log the reference count ' thing and will come back with the results soon.

Regards,

A query in bitmap routine

jossion29-Feb-08 0:00

jossion

29-Feb-08 0:00

Below is the code snippet I wrote for displaying pixel values onto the screen in MFC. The pixel values are stored in buffer disp_frame. But nothing appears on screen. Could anyone debug this code.

void CBluetooth_decoderDlg::OnTimer(UINT nIDEvent)
{
// TODO: Add your message handler code here and/or call default
int p=0,i=0,j=0,q=0;

// extern int disp_frame[50][144][176];

///////////////////////
BITMAPINFOHEADER bmi;
BITMAPINFO bm;
RGBQUAD rgbarray[256];

bmi.biSize = sizeof(BITMAPINFOHEADER);
bmi.biWidth = 176;
bmi.biHeight = 144;
bmi.biPlanes = 1;
bmi.biBitCount = 8;

bmi.biCompression = BI_RGB;
bmi.biSizeImage = 0;
bmi.biXPelsPerMeter = 0;
bmi.biYPelsPerMeter = 0;
bmi.biClrUsed = 0;
bmi.biClrImportant = 0;

bm.bmiHeader = bmi;

for (int color_index = 0; color_index < 256; color_index++)
{
rgbarray[color_index].rgbBlue = i;
rgbarray[color_index].rgbGreen = i;
rgbarray[color_index].rgbRed = i;
rgbarray[color_index].rgbReserved = 0;
}
bm.bmiColors[1] = rgbarray[0];

/////////////////////

CRect rcClient;
GetClientRect(rcClient); // See Note 1
rcClient.right=176;
rcClient.bottom=144;

CDC MemDC,*pDC;
CBitmap MemBitmap,*drawmem;

pDC = this->GetDC(); // Get Current DC

MemDC.CreateCompatibleDC(pDC);

CreateDIBSection(MemDC,bm,DIB_RGB_COLORS,disp_frame,NULL,0);
CBitmap *pOldBitmap =MemDC.SelectObject(&MemBitmap);

pDC->BitBlt(150,100,176,144,&MemDC,0,0,SRCCOPY);

MemDC.SelectObject(pOldBitmap);

ReleaseDC(pDC);

}

Re: A query in bitmap routine

CPallini29-Feb-08 0:18

CPallini

29-Feb-08 0:18

Have a look at CreateDIBSection documentation [^]. It states the 5th parameter (a pointer to a pointer) is an [out] one. It means you have to pass the address of a pointer and, on return, that pointer will contain the address of the allocated DIB section buffer, then you have to change the bit values of such buffer, according to disp_frame values, before selecting it into device context.
Smile | :)

Re: A query in bitmap routine(CDC versus HDC)

jossion4-Mar-08 1:43

jossion

4-Mar-08 1:43

rtant = 0;

bm.bmiHeader = bmi;

for (int color_index = 0; color_index < 256; color_index++)
{
rgbarray[color_index].rgbBlue = i;
rgbarray[color_index].rgbGreen = i;
rgbarray[color_index].rgbRed = i;
rgbarray[color_index].rgbReserved = 0;
}
bm.bmiColors[1] = rgbarray[0];

/////////////////////

CRect rcClient;
GetClientRect(rcClient); // See Note 1
rcClient.right=176;
rcClient.bottom=144;

CDC MemDC,*pDC;
CBitmap MemBitmap,*drawmem;

pDC = this->GetDC(); // Get Current DC

MemDC.CreateCompatibleDC(pDC);

CreateDIBSection(MemDC,bm,DIB_RGB_COLORS,disp_frame,NULL,0);
CBitmap *pOldBitmap =MemDC.SelectObject(&MemBitmap);

pDC->BitBlt(150,100,176,144,&MemDC,0,0,SRCCOPY);

MemDC.SelectObject(pOldBitmap);

ReleaseDC(pDC);

}

This was the piece of code which was posted previously. But the CreateDIBSection code
CreateDIBSection(MemDC,bm,DIB_RGB_COLORS,disp_frame,NULL,0); was having MemDC is a CDC type. But actually it should be HDC type. So I have rewritten the code as

HDC hDC;
hDC = CreateDC("DISPLAY",NULL,NULL,NULL);
HDC memDC = CreateCompatibleDC(hDC);
CreateDIBSection(hDC,bitmap,DIB_PAL_COLORS,ppbits,NULL,0);
HBITMAP memBM = CreateCompatibleBitmap(hDC,176,144);
SelectObject(memDC,memBM);

BitBlt(memDC,150,100,176,144,hDC,0,0,SRCCOPY);

But CreateDIBSection is creating exception. What could be the reason. Basically I could not get the difference between CDC and HDC. Could anyone give a clear solution to my problem. I am actually trying to display a grayscale image which exists as R=G=B values in memory.

Re: A query in bitmap routine(CDC versus HDC)

CPallini4-Mar-08 2:08

CPallini

4-Mar-08 2:08

Please surround code snippets with <pre> tags.

(1) What error message are you receiving?
(2) how did you define ppbits?

Re: A query in bitmap routine(CDC versus HDC)

jossion4-Mar-08 19:01

jossion

4-Mar-08 19:01

The error message was Unhandled exception in decoder.exe(GDI32.dll): 0xc0000005 : Access Violation

the declaration for ppbits was void **ppbits.
Once this CreateDIBSection works i thought of filling ppbits with pixel values. That's why that particular piece of code is not available

Re: A query in bitmap routine(CDC versus HDC)

CPallini4-Mar-08 21:35

CPallini

4-Mar-08 21:35

jossion wrote:
the declaration for ppbits was void **ppbits

The above is wrong.
You have to declare a pointer to void, for instance

void * pbits;

and then pass the address of the pointer (i.e. &pbits) to CreateDIBSection:

CreateDIBSection(hDC,bitmap,DIB_PAL_COLORS, &pbits, NULL,0);

How to flash the taskbar icon of a certain frame ?

Ahmed Charfeddine28-Feb-08 23:59

Ahmed Charfeddine

28-Feb-08 23:59

Hello evry body, how is it possible to flash the icon of a certain frame window, in order to capture the attention of the user and see the asynchrounous event that happened and which relates to the frame whose icon is highlighted ?
Thank you in advance.

Re: How to flash the taskbar icon of a certain frame ?

Rajesh R Subramanian29-Feb-08 0:02

Rajesh R Subramanian

29-Feb-08 0:02

See FlashWindow()[^]

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Re: How to flash the taskbar icon of a certain frame ?

Ahmed Charfeddine29-Feb-08 3:36

Ahmed Charfeddine

29-Feb-08 3:36

Thank you thank you very much !

Re: How to flash the taskbar icon of a certain frame ?

Rajesh R Subramanian29-Feb-08 3:44

Rajesh R Subramanian

29-Feb-08 3:44

You're welcome.

Nobody can give you wiser advice than yourself. - Cicero
.·´¯`·->Rajesh<-·´¯`·.
Codeproject.com: Visual C++ MVP

Can't find the win32 C/C++ equivalents of the VB functions SelStart, SelLength, and SelText

glyfyx28-Feb-08 22:48

glyfyx

28-Feb-08 22:48

I'd like to search the active window's client area for a given string and highlight it.

I've done this in VB using SelStart and SelLength.

I'm sure I've seen the same functionality available from a conventional Windows program, but can't remember what the win32 API calls are.

Does anyone know, or have tips on how to find out?

Thanks for the assist.

glyfyx

Re: Can't find the win32 C/C++ equivalents of the VB functions SelStart, SelLength, and SelText

CPallini28-Feb-08 23:04

CPallini

28-Feb-08 23:04

There is EM_SETSEL message though it works with edit boxes (or EM_EXSETSEL, with Rich Edit controls). AFAIK VB6 itself allows SelStart and SelLength only inside controls (i.e. they are TextBox methods).
Smile | :)

Re: Can't find the win32 C/C++ equivalents of the VB functions SelStart, SelLength, and SelText

glyfyx6-Mar-08 9:20

glyfyx

6-Mar-08 9:20

Just a word of thanks - appreciated!

glyfyx

Re: Can't find the win32 C/C++ equivalents of the VB functions SelStart, SelLength, and SelText

JohnCz4-Mar-08 13:03

JohnCz

4-Mar-08 13:03

If this is a Win32 application without using MFC, create window as a child of the main window; use "edit" window class. You may want to subclass edit window but it is not necessary.

Use EM_* messages to tell edit window what to do. See MSDN for more information. EM_ messages are defined in WINUSER.H. Handle notification messages from control in a parent window, to see what control is doing. Notification code are also defined in WINUSER.H and are delivered as parameter of WM_COMMAND message.

For MFC application use CEdit class and call SetSel member function. Again, see MSDN for members reference. You can add notification handlers in a parent of edit control using Wizard.

JohnCz
MS C++ MVP

Re: Can't find the win32 C/C++ equivalents of the VB functions SelStart, SelLength, and SelText

glyfyx6-Mar-08 9:19

glyfyx

6-Mar-08 9:19

Thanks for taking time to provide such a complete answer - much appreciated!

glyfyx

Re: Can't find the win32 C/C++ equivalents of the VB functions SelStart, SelLength, and SelText

JohnCz6-Mar-08 17:30

JohnCz

6-Mar-08 17:30

You are very welcome. Glad to be of help.

JohnCz
MS C++ MVP