Re: Help aout paint none-client area - C / C++ / MFC Discussion Boards

Beveloper11-Jul-07 7:00

11-Jul-07 7:00

I need a simple Windows application to detect messages from a USB drive. When the application detects that a USB device has been inserted, I need to launch another application.

I have found an example which works in .NET environments but I can't guarantee that all my users will be working on .NET-supported platforms.

Does anyone know of a simple C++ application containing a basic message loop that I can adapt? I don't care about the UI.

Alternately, is there an easy way to convert .NET code so that it will work on a non-.NET platform?

I'm working in Visual C++ 2005 Express.

Thanks!

Re: USB device message detector

ksrameshkanth11-Jul-07 21:59

ksrameshkanth

11-Jul-07 21:59

Hi,
I think you can handle ON_WM_DEVICECHANGE(). Also refer the following link
http://www.codeproject.com/system/HwDetect.asp

Regards,
Rameshkanth

Cut a bitmap under GDI+

Chen-XuNuo11-Jul-07 6:36

Chen-XuNuo

11-Jul-07 6:36

I want to cut a bitmap and save the selection I cut what is anomalistic under GDI+.Is there any program that I can refer to?

Thanks.

Re: Cut a bitmap under GDI+

Mark Salsbery11-Jul-07 9:04

Mark Salsbery

11-Jul-07 9:04

Do you mean something like this?

// CropLeft, CropTop, CropWidth, CropHeight are INTs defining the portion of the source image
// to copy to the new destination image
 
Gdiplus::Bitmap SrcBitmap(...);
...
Gdiplus::Bitmap DstBitmap(CropWidth, CropHeight, SrcBitmap.GetPixelFormat()); 
Graphics DstGraphics(&DstBitmap);
DstGraphics.DrawImage(&SrcBitmap, 0, 0, CropLeft, CropTop, CropWidth, CropHeight, UnitPixel);

Mark

Mark Salsbery
Microsoft MVP - Visual C++

This episode brought to you by the number 3

Re: Cut a bitmap under GDI+

Chen-XuNuo11-Jul-07 19:36

Chen-XuNuo

11-Jul-07 19:36

I am not so familiar with GDI+,so I don't know that the code your provided can wheather achieve my purpose definitely.What I mean is the region in the bitmap is not necessarily a rect,it is mainly region that I draw with mouse.So it is a irregular region.Could you get it?;P

Re: Cut a bitmap under GDI+

Mark Salsbery12-Jul-07 5:08

Mark Salsbery

12-Jul-07 5:08

Chen-XuNuo wrote:
What I mean is the region in the bitmap is not necessarily a rect,it is mainly region that I draw with mouse.

You could create a GraphicsPath object from the mouse points defining the outline and then
use Graphics::SetClip() to set the clipping region to the GraphicsPath in the destination
Graphics object before drawing the bitmap.

Mark

Mark Salsbery
Microsoft MVP - Visual C++

This episode brought to you by the number 3

Help aout paint none-client area

kcynic11-Jul-07 6:22

kcynic

11-Jul-07 6:22

I have a dialog-based program,
I want to draw my own title bar,so I completement ON_WM_NCPAINT() message of the dialog.
In the OnNcPaint() funtion,I wrote:
CDC* pDC=GetWindowDC();
CDC memDC;
BOOL ret=memDC.CreateCompatibleDC(pDC);
int nSaveDC=pDC->SaveDC();
CBitmap bmp;
ret=bmp.LoadBitmap(IDB_LOGIN);//IDB_LOGIN is a bitmap resource ID
memDC.SelectObject(&bmp);
CRect rc;
GetWindowRect(&rc);
ScreenToClient(&rc);
ret=pDC->BitBlt(0,0,rc.Width(),m_captionRect.Height(),&memDC,0,0,SRCCOPY);
bmp.DeleteObject();
ReleaseDC(&memDC);

pDC->RestoreDC(nSaveDC);

the code works well when the dialog was shown first time,but when the dialog should be redrawn,the title bar went back to its default look(the blue bar).
Someone would like to tell me why?And how to resolve it?
Thanks.

GOOD LUCK.

Re: Help aout paint none-client area

DevMentor.org12-Jul-07 12:01

DevMentor.org

12-Jul-07 12:01

i am not sure but it sounds like you need to send an update to your non-client area Big Grin | :-D

Yours Truly, The One and Only!

Re: Help aout paint none-client area

kcynic13-Jul-07 1:00

kcynic

13-Jul-07 1:00

Thanks.
Now,it works well.But if you would like to tell me how to make the client area's left-bottom and right bottom is round conor?

Re: Help aout paint none-client area

DevMentor.org13-Jul-07 12:10

DevMentor.org

13-Jul-07 12:10

i'm afraid i have not done GDI and custom drawing in a sometime Smile | :)

these days most of my development is focued on non-gui core development!

i am sure you should be able to find custom driawing how-to on this site understand mfc section, have you tryed that?

Yours Truly, The One and Only!

Re: Help aout paint none-client area

kcynic13-Jul-07 12:26

kcynic

13-Jul-07 12:26

Thanks,but I has searched in this site faild.

GOOD LUCK.

Re: Help aout paint none-client area

DevMentor.org13-Jul-07 20:46

DevMentor.org

13-Jul-07 20:46

ok here's how to do it if you're resourceful.

the first time around before you window come up you will have to grab the background and draw it into a z-buffer(off-screen buffer), only grab the rectangle area of the bottom portion you will need the round corned, follow me, then you do your non-client magic drawing in the bottom portion of your window!

that is the first step, the 2nd step once you get this working it to make it be able to grab area while your window is getting move around...remember to paint back the original screen background if that is required, most likely you will not have to worry about this last part.

hope that helps! remember just use the window DC and you will need to covert the between screen point and client point!

hope that help....learn to do this for yourself, you will be a better developer for it Poke tongue | ;-P

Yours Truly, The One and Only!

Convert Int to Byte

simoncoul11-Jul-07 6:19

simoncoul

11-Jul-07 6:19

I'm trying to convert and short int into 2 bytes to be send through an ethernet comm. This is what I'm trying to do:

    char calcsendbuf[3];
short int data;
printf("Please Enter The Data:");
scanf("%d", &data);
calcsendbuf[0] = char(data % 256);
calcsendbuf[1] = char(floor(double(data/256)));
printf("byte 0: %u\n", calcsendbuf[0]);
printf("byte 1: %u\n", calcsendbuf[1]);

I input 32767 as the data and it should be printing 255 and 127, but I'm getting 4294967295 and 127. Any ideas of what is going wrong here, or maybe a different way of doing things?

Thanks

Re: Convert Int to Byte

David Crow11-Jul-07 7:21

David Crow

11-Jul-07 7:21

simoncoul wrote:
I input 32767 as the data and it should be printing 255...

Since a char has a range of -128 to 127, trying to assign it a value of 255 will not do what you want.

"A good athlete is the result of a good and worthy opponent." - David Crow

"To have a respect for ourselves guides our morals; to have deference for others governs our manners." - Laurence Sterne

Re: Convert Int to Byte

Cyrilix11-Jul-07 7:21

Cyrilix

11-Jul-07 7:21

You will never get 255 with a signed char, since chars are only 1 byte (your range is 2^7 both ways). Use the unsigned char instead.

Re: Convert Int to Byte

simoncoul11-Jul-07 7:52

simoncoul

11-Jul-07 7:52

Ok using the unsigned char worked for the display but the send function in winsocks asks for a char *, how do I go about getting sending a single byte of 255 through ethernet using winsocks.

Re: Convert Int to Byte

Cyrilix11-Jul-07 8:13

Cyrilix

11-Jul-07 8:13

To be honest, I have no clue. I won't pretend that I know anything about winsocks, but IF (and that's a big if) all it has to do is with type conversion, you can simply cast it on the send, and cast it back when you receive it.

Re: Convert Int to Byte

simoncoul11-Jul-07 8:25

simoncoul

11-Jul-07 8:25

Thanks for the help I took my unsigned char array and cast it as char * in the send function and it all works now.

Thanks for all the help!!!

Parameter passsing between classes

chaitannya_m11-Jul-07 6:03

chaitannya_m

11-Jul-07 6:03

Hi guy this is so lame i cant pass parameters between classes, i feel like commiting sucide Blush | :O

(
anyways

I have used a public variable in say class A
Public:
long iSelPackageItemID;

and assigned the value in function...
setPackageID()
{
iSelPackageItemID=some value;

}
then i have declared a function
long getPackageID()
(
return iSelPackageItemID;

)
after a long long time i call the function getPackageID()
from some another class say B and i am getting garbage value i.e. getPackageID() is returning garbage.

Whatever is the solution i just want the value from iSelPackageItemID in class B which is assigned in class a.

Re: Parameter passsing between classes

Electronic7511-Jul-07 6:10

Electronic75

11-Jul-07 6:10

Maybe you have casting problem. post the code when you call setPackageID from your B class (before taking any action for suicide Smile | :)

)

Re: Parameter passsing between classes

chaitannya_m11-Jul-07 6:54

chaitannya_m

11-Jul-07 6:54

No casting since all the variables are long. I checked in the debug mode that the value is retained in the class as along the variable is in scope, but garbage value is assigned once the value goes beyond the scope. I guess i need to increase the scope of variable to application variable.. How do i do it...?

Re: Parameter passsing between classes

sheshidar11-Jul-07 18:07

sheshidar

11-Jul-07 18:07

I dont know how exactly u had written the class,
I assumed some and written like this..

class A<br />
{<br />
public: <br />
long iSelPackageItemID;<br />
<br />
A()<br />
{<br />
<br />
iSelPackageItemID=100;<br />
}<br />
<br />
//and assigned the value in function...<br />
setPackageID()<br />
{<br />
iSelPackageItemID=200;<br />
<br />
<br />
}<br />
//then i have declared a function <br />
long getPackageID()<br />
{<br />
return iSelPackageItemID;<br />
<br />
}<br />
<br />
<br />
};<br />
<br />
class B<br />
{<br />
public:<br />
	 A ob1;<br />
<br />
<br />
<br />
};<br />
<br />
int main()<br />
{<br />
<br />
<br />
B ob2;<br />
A ob;<br />
cout<<ob.getPackageID()<<endl;<br />
<br />
cout<<ob2.ob1 .getPackageID ()<<endl;<br />
<br />
<br />
<br />
return 0;<br />
<br />
}

if ur code is similar to this than u got the solution.
If this the right solution that ur problem is,
u had given some valsue to iSelPackageItemID in the setPackageID() method, but when u create the onject to class A or B, ur members functions will not call and the valuse of setPackageID is not intialised, so give valuse to setPackageID either in constructor or call the setPackageID() function before calling getPackageID()<< method.

Re: Parameter passsing between classes

chaitannya_m11-Jul-07 7:29

chaitannya_m

11-Jul-07 7:29

Well i solved the problem time being.
by declaring
extern long iSelPackageItemID in the .h file
and long iSelPackageItemID in .cpp file

i got help from here http://www.codeguru.com/forum/showthread.php?threadid=427587

But the core OOP funda remains unanswered, i know this is going beyond the scope but just for knowledge sake. I am also working in java and i haven't seen such kind of syntax, also in a desingning book it stated not to use a global variable since it voilates the basic rules of OOP. So is the above code a good programming practise...?

Re: Parameter passsing between classes

JudyL_MD11-Jul-07 7:40

JudyL_MD

11-Jul-07 7:40

How are you creating "some value"? The first thing that comes to mind is that it is a variable that has gone out of scope between when you assign it and when you try to reference it.

Judy

Re: Parameter passsing between classes

chaitannya_m11-Jul-07 9:04

chaitannya_m

11-Jul-07 9:04

I am not clear on this thing ... but now it looks like pretty much that it's going out of reference. My OOP fundas are weak... but just one question when i assign a value to a class member A, then i declare an obj of class B so when i try to access the member from a through B does it go out of scope..?

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