C / C++ / MFC Discussion Boards

5-Apr-01 6:16

Hi all,
could someone please tell me how to do drawing on a dialog when the user presses a button. (for example draw a sine-wave or something)...

i'd be really grateful for a detailed example, on howto get the dc, and do the drawing stuff...i did not see through the examples on this page so please help me

Re: Drawing

C^hris L^osinger5-Apr-01 7:06

C^hris L^osinger

5-Apr-01 7:06

when the user presses the button, call InvalidateRect(rect, TRUE) where rect is the place where your sine wave will be drawn.

then, in the dialog's OnPaint function, draw the sine wave in that rect. use the DC that OnPaint uses.

for drawing stuff, you'll need a brush (if you want to draw a background color) and a pen (to draw the wave).

// fill the background with medium gray
CBrush myBrush;
myBrush.CreateSolidBrush(RGB(128,128,128));
CBrush *pOldBrush = dc.SelectObject(&myBrush);
dc.Rectangle(rect);
dc.SelectObject(pOldBrush);
myBrush.DeleteObject();

// draw a pair of lines
CPen myPen;
myPen.CreatePen(PS_SOLID, 1, RGB(0,0,0));
CPen *pOldPen = dc.SelectObject(&myPen);
dc.MoveTo(rect.left, rect.top);
dc.LineTo(rect.right, rect.bottom);
dc.LineTo(rect.right/2, rect.top);
dc.SelectObject(pOldPen);
myPen.DeleteObject();

-c

------------------------------
Smaller Animals Software, Inc.
http://www.smalleranimals.com

Re: Drawing

6-Apr-01 1:08

Well somehow it doesnt work, some strange page fault error occurs...

Can you please send me an example , where a simple line is drawn into a dialog ? or perhaps even in a static control... my email adress is : kixxass@gmx.net

Re: Drawing (aha......)

6-Apr-01 6:47

well now the drawing stuff works, but not wenn i press the button, its drawed right at startup... at least i see that when i press the btn, the rect is redrawn.. where exactly do i have to put that stuff in the OnPaint ? into that part with IsIconic() ??? help me plz Smile | :)

InstallShield fo VC++ 6

4-Apr-01 14:41

Can anyone tell me where a good resource on InstallShield fo VC++ 6 is. The help files and me apparently don't get along. I'm looking for a good tutorial.
Thanks.

Re: InstallShield fo VC++ 6

Christian Graus4-Apr-01 15:12

Christian Graus

4-Apr-01 15:12

The website has a knowledge base and some forums, from memory. I migrated to Setup Factory ages ago.

Christian

The content of this post is not necessarily the opinion of my yadda yadda yadda.

To understand recursion, we must first understand recursion.

Re: InstallShield fo VC++ 6

4-Apr-01 15:18

Yea, but the knowledge base and me didn't get along either. I don't really know what to look for, hence I need a tutorial. Smile | :)

But thx though...

Line Numbers in Visual Studio??

uniken4-Apr-01 13:56

uniken

4-Apr-01 13:56

Does anyone know of an add-in which will let me show line numbers on the left of the source lines in Visual Studio? It would help for debugging bison parsers.

Thanks,

Chris

Re: Line Numbers in Visual Studio??

Erik Thompson4-Apr-01 19:30

Erik Thompson

4-Apr-01 19:30

Ctrl-G doesn't work?

Re: Line Numbers in Visual Studio??

uniken4-Apr-01 19:51

uniken

4-Apr-01 19:51

Ctrl G does work but its sometimes a bit tedious. The parsers I'm writing have a lot of rules which emit their line number when Flex is run in debug mode. It's much easier to browse the grammar with line numbers displayed on screen. Currently I'm using PFE to do this and switching back to VC to make changes.

Cheers,

Chris

Windows 2000 and Visual C++/MFC

Drake Elsari4-Apr-01 11:10

Drake Elsari

4-Apr-01 11:10

Hi, I was wondering if anyone knew of any new Classes or features that Win2k gives MFC. And if you need to get a new version to use for Win2k.

Re: Windows 2000 and Visual C++/MFC

Christian Graus4-Apr-01 13:16

Christian Graus

4-Apr-01 13:16

You need to get the latest SDK in order to use features such as transparent windows, but to my knowledge, the new functions are all Win32 API, I don't believe they have added to the MFC dll at all.

Of course, I could be wrong Smile | :)

Christian

The content of this post is not necessarily the opinion of my yadda yadda yadda.

To understand recursion, we must first understand recursion.

CreateEnhMetafile (EMF) and WMF

MikeG4-Apr-01 10:20

MikeG

4-Apr-01 10:20

I have the following problem:

I am creating an Enhanced metafile using OpenGL and then trying to convert it to a metafile (WMF).

Right now I have to do the following:
HDC hDCEnhMetaFile = CreateEnhMetaFile(.."myfile.emf");
...do my drawing...
CloseEnhMetaFile(hDCEnhMetaFile);
...
HENHMETAFILE hEnhMetafile = GetEnhMetafile( "myfile.emf")
GetWinMetafileBits( hEnhMetafile, pBuffer, numBytes );

HMETAFILE hMemMetafile = GetMetafile()
hMemWinMetaFile = SetMetaFileBitsEx( numBytes, pBuffer )

hFileWinMetaFile = CopyMetaFile(hMemWinMetaFile, "myfile.wmf")

DeleteMetaFile( hFileWinMetaFile )
DeleteMetaFile(hMemWinMetaFile )
DeleteEnhMetaFile( hEnhMetaFile )

I do NOT want to actually create an EMF file. The problem is the CreateEnhMetafile function returns an HDC not HENHMETAFILE which is required for GetWinMetafileBits - I tried to just cast the HDC to an HENHMETAFILE but this doesn't seem to work (invalid parameter error). Is there someway to get the HENHMETAFILE from an HDC? Any example code out there (I can't find anything)?

Thanks
Mike

SetFocus???

Richard Cheng4-Apr-01 8:05

Richard Cheng

4-Apr-01 8:05

My program is a single document program with some dialog boxes for input. When the user finished the input, the "main" window loses its focus, therefore, I have to press Spacebar first in order to input something to the main window. How can I SetFocus back to the window. I tried several ways but don't work.

Thanks

Re: SetFocus???

Michael Dunn4-Apr-01 20:14

Michael Dunn

4-Apr-01 20:14

To set the focus to your main frame window: AfxGetMainWnd()->SetFocus();

--Mike--
http://home.inreach.com/mdunn/
All your base are belong to ME~!

CreateCompatibleBitmap fails for a WMF dc.

4-Apr-01 6:53

Hi, I have some code that will succeed when I call CreateCompatibleBitmap on a dc that in an "Enhanced" meta file dc. However, the same code will not work when the dc is the older WMF syle??? I do not know much about metafiles so I'm not sure if CreateCompatibleBitmap is suppose to work for them? Thanks Blush | :O

)

=== WMF ======================== This does not work ===========

CMetaFileDC* pCdcMeta = new CMetaFileDC();
CDC* pScreenDC = GetDC();
CRect rcClient;
CBitmap* pBitmap = new CBitmap();

GetClientRect(rcClient);

CString cstrFileName("c:\\tmp.wmf");
BOOL bRetCode = pCdcMeta->Create(cstrFileName);

// the m_hObject in pBitmap remains NULL. GetLastError only returns zero!

pBitmap->CreateCompatibleBitmap(pCdcMeta, rcClient.Width(), rcClient.Height());
DWORD dw = GetLastError();

=== EMF ======================== This DOES work ===========

CMetaFileDC* pCdcMeta = new CMetaFileDC();
CDC* pScreenDC = GetDC();
CRect rcClient;
CBitmap* pBitmap = new CBitmap();

GetClientRect(rcClient);

CString cstrFileName("c:\\tmp.wmf");
BOOL bRetCode = pCdcMeta->CreateEnhanced(pScreenDC, cstrFileName, NULL, NULL);

// the m_hObject in pBitmap remains NULL. GetLastError only returns zero!

pBitmap->CreateCompatibleBitmap(pCdcMeta, rcClient.Width(), rcClient.Height());
DWORD dw = GetLastError();

BobSco

Vanished Hotkeys

4-Apr-01 5:39

Suddenly, all of the hotkeys displayed in my menus and buttons (that is, the characters that are underlined because they are preceded by a '&') do not display the underline. They still function and the underlines appear when I hit the Alt key (which seems to toggle them on and off).

I know that these hotkeys appeared properly not too long ago.

Any suggestions as to what I might have done to make this happen?

Thanks.

Paul Ebert

Re: Vanished Hotkeys

Jim A. Johnson4-Apr-01 6:23

Jim A. Johnson

4-Apr-01 6:23

This is due to a design error in Windows 2000 and Windows 98 ME. Someone at MS seemed to think that the underlines were a bad idea, so they added a "feature" to disable these unless the Alt key is held down.

Fortunately, someone else apparently realized the silliness of this notoin, so they added a switch in the Desktop Properties dialog to fix it. Go to Desktop | Properties | Effects and Uncheck the "Hide keyboard navigation.. blah blah" switch. Your Windows system will work correctly again.

Re: Vanished Hotkeys

Peter Pearson6-Apr-01 0:15

Peter Pearson

6-Apr-01 0:15

You've probably got Windows 2000 and have got them turned off in the Appearence tab of the Display Properties property page.

Cheers,
Peter Pearson

STL: How can I delete a <list>...

Braulio Dez4-Apr-01 5:28

Braulio Dez

4-Apr-01 5:28

Hi !,

I´m new using this STL, now I can add members to a list an iterate though that list, but ... still don´t now how to delete members from it, and free the list in a right way...

Can anybody help me ? Thanks a lot,Bye !

Braulio

Re: STL: How can I delete a <list>...

MikeG5-Apr-01 1:19

MikeG

5-Apr-01 1:19

To clear the whole list:
list.erase( list.begin(), list.end() );
To delete a single item:
// iter is the iterator of the item you want to delete
// iter = list.begin(); // 1st item in list
// iter = &(list.at(iIndex)); //iItem in lsi
list.erase( iter );

Hope this helps
Mike

Hide classes from ClassView

Luis Barreira4-Apr-01 5:27

Luis Barreira

4-Apr-01 5:27

How can I hide several classes and typedefs from the class view tree?

Re: Hide classes from ClassView

Erik Funkenbusch4-Apr-01 8:45

Erik Funkenbusch

4-Apr-01 8:45

You can do two things. The easiest, if the class is defined in it's own header file seperate from other things, just remove it from the "Headers" folder in the File View.

Second, you can add the header file to a text file called sysincl.dat in the ...\Microsoft Visual Studio\Common\MSDev98\Bin directory.

To my knowledge, there isn't a way to remove just a class, you have to remove everything that's in a file.

Initialize MFC-ODBC app from query

Robert Bushlow4-Apr-01 4:49

Robert Bushlow

4-Apr-01 4:49

I currently have an MFC-ODBC based application with
the wizard generated initialization. I would like
to initialize from a SELECT FROM WHERE type query.
My current code as follows:

CRegiDBSet::CRegiDBSet(CDatabase* pdb)
: CRecordset(pdb)
{
//{{AFX_FIELD_INIT(CRegiDBSet)
m_CourseID = _T("");
m_CourseTitle = _T("");
m_Hours = 0;
m_StudentID = 0;
m_CourseID2 = _T("");
m_SectionNo = _T("");
m_Grade = _T("");
m_InstructorID = _T("");
m_Name = _T("");
m_RoomNo = _T("");
m_CourseID3 = _T("");
m_SectionNo2 = _T("");
m_InstructorID2 = _T("");
m_RoomNo2 = _T("");
m_Schedule = _T("");
m_Capacity = 0;
m_StudentID2 = 0;
m_Name2 = _T("");
m_GradYear = 0;
m_nFields = 19;
//}}AFX_FIELD_INIT
m_nDefaultType = snapshot;
}

CString CRegiDBSet::GetDefaultConnect()
{
return _T("ODBC;DSN=Student Registration");
}

CString CRegiDBSet::GetDefaultSQL()
{
return _T("[Course],[Enrollment],[Instructor],[Section],[Student]");
}

This brings in all of the rows from all of the tables.
I would like to initialize from a select; something like the following.
I have already tried substituting this in the GetDefaultSQL proc.

_T("
SELECT Course.CourseID as 'ID',
Course.CourseTitle as 'Title',
Section.Hours as 'Hours',
Section.RoomNo as 'Room',
Instructor.m_InstructorID
FROM Course, Enrollment, Instructor, Section, Student
WHERE Course.CourseTitle like 'Math'
ORDER BY 'ID', 'Room'
");

Additionally the wizard generates a large list of variables
corresponding to all of the columns in the tables. I would
like to initialize my date with the results from the query
shown above. Working example code would be very helpful.
Thank You.

CCheckBox buttons

Roger4-Apr-01 4:27

Roger

4-Apr-01 4:27

I am trying to use CCheckBox buttons (push-like property set) on a dialog. When one is selected I need to change the text color and the background color of the selected button. I am using CColorButton in order to do this with standard CButtons, but how can I change the color of these CCheckBox buttons?

Roger
Software Engineer

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