C / C++ / MFC

9-Mar-09 15:08

I am looking at the book, “Windows 95 with MFC” by Jeff Prosise. In this book, there are two techniques for implementing scroll bars given. One approach is to process the messages ON_WM_VSCROLL and ON_WM_HSCROLL. The other approach is to use the class CScrollView.

I am currently using the first approach and I find that my application has the following problem: If I run the program and using the mouse I make the window small (in the horizontal direction) a horizontal scroll bar shows up. This is to be expected. I then use the mouse to move the scroll bar to the middle of the window. Now, I minimize the window and then maximize the window. After doing this, I would expect the text and the input field (of type CEdit) to be drawn aligned on the screen. However, this is not the case. The text is shifted to the right (at least relative to the input field). I do not understand why and I am hoping somebody here can tell me what I am missing.

Do you think switching to CScrollView will solve my problem?

Thanks

Bob

Re: Scroll Bars

BobInNJ9-Mar-09 16:18

Iain Clarke, Warrior Programmer

9-Mar-09 16:18

I think I figured out what I was doing wrong. When the window gets resized, I need to move
the child windows that I have in my application. The way to do this is to use the method
CWnd::MoveWindow.

The window gets moved by the offset of the scrollbar. Does this make sense? What, if any, am I missing?

Thanks

Bob

Re: Scroll Bars

Iain Clarke, Warrior Programmer10-Mar-09 1:27

10-Mar-09 1:27

Your error will be heavily dependent on the fine detail of your application.

But you need to handle the WM_SIZE message to change the details of your scroll bars.
Have a look at the SCROLLINFO structure, and also the nPage member.

Then you'll want to call GetScrollInfo in your painting routine, so you know to offset your painting by a certain amount.

If you *can* use CScrollView, it does all this work for you. And set's up the DC you draw on to with SetViewportOrg etc so it's invisible for you.

I don't use it, and I do all this scroll bar myself - and there's quite a few things to trip you up.

Reading your message again... I'm not sure where this CEdit is coming in. Maybe you should be using a CFormView, put your controls on a dialog, and letting MFC do all this work instead?

Iain.

Codeproject MVP for C++, I can't believe it's for my lounge posts...

Re: Scroll Bars

BobInNJ10-Mar-09 4:19

C HELP PLEASE!! [modified]

10-Mar-09 4:19

Iain,

Thanks for the response. I have a field of type CEdit defined in the main window class of the application. I will definitely take a look at the class CFormView.

Is there a reason why I might not be able use CScrollView?

Thanks

Bob

posidonofthecode9-Mar-09 13:55

posidonofthecode

9-Mar-09 13:55

/* IM TRYING TO WRITE IT SO THAT I CAN SEE EACH LETTER AS IT IS BEING WRITTEN BY THE COMPUTER*/
/* Thanks D'Oh! | :doh:

in advance*/
#include <stdio.h>
main()
{

printf("\n\nH");
sleep(2);
printf("e");
sleep(2);
printf("y");
sleep(2);

return 0;
}

/* Im trying to run it one letter at a time*/

modified on Monday, March 9, 2009 8:30 PM

BobInNJ9-Mar-09 14:14

9-Mar-09 14:14

I think this is what you want:

#include <stdio.h><br />
main()<br />
{<br />
	printf("\n\nH");<br />
	printf("e"); ;<br />
	printf("y");<br />
<br />
	printf( "\n" );<br />
	return 0;<br />
}

Bob

posidonofthecode9-Mar-09 14:41

posidonofthecode

9-Mar-09 14:41

Yes thats good but i want two second delay between each letter written, and going horizontally

BobInNJ9-Mar-09 15:07

9-Mar-09 15:07

Now, if our goal is to write this in portable C, then there is no way to write the sleep function. However, if you use Windows Specific functions, then I believe you can do it. Here is how:

#include <windows.h><br />
<br />
#include <stdio.h><br />
<br />
main()<br />
{<br />
	printf("\n\nH");<br />
	Sleep( 2000 );<br />
	printf("e");<br />
	Sleep( 2000 );<br />
	printf("y");<br />
<br />
	printf( "\n" );<br />
	return 0;<br />
}

The argument to Sleep is the time in milliseconds. I hope this helps. Feel free to ask a follow up question.

Bob

VBasic to VC++ syntax conversion

David Crow9-Mar-09 15:58

David Crow

9-Mar-09 15:58

Assuming you want a 2ms delay (which is not discernable by the human eye) in between each letter, what you have is fine.

"Old age is like a bank account. You withdraw later in life what you have deposited along the way." - Unknown

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

Software20079-Mar-09 11:20

Software2007

9-Mar-09 11:20

Hello,

I need to translate some header file for function calls from Basic to C++ .... I am clueless when it comes to VBasic syntax...could someone provide me with some help on something like the following:

Declare Function Draw Lib "PDF_In_The_Box.dll" (ByVal hBox As Long, ByVal aX As Long, ByVal aY As Long, ByVal hBitmap As Long) As Long
//////////

Sub CallBox(ByVal aFunctionCall As Long)
  Dim Msg As String * 255
  Dim n As Long

  If aFunctionCall = -1 Then
    n = GetErrorMsg(Msg)
    MsgBox Msg, 16, "PDF In-The-Box"
    Stop
  End If
End Sub
////////////////////
Function GetStr(ByVal aBoxHandle As Long, ByVal aPropID As Long) As String
  Dim Result As String * 255
  CallBox GetStrProp(aBoxHandle, aPropID, Result)
  GetStr = Result
End Function
///////////////////////////

sft

Re: VBasic to VC++ syntax conversion

0x3c09-Mar-09 11:48

0x3c0

9-Mar-09 11:48

For a start, the Draw function should come with a header file. If it doesn't, then load "PDF_In_The_Box.dll" using LoadLibrary(), use GetProcAddress() to get the address of the Draw() function, and call the function pointer (I think you may need to do an explicit cast here)

As for the rest:
String * 255 is a pointer to a fixed length char array of length 255 (I think it's a pointer, not sure here)
MsgBox just shows a box, it's easily ignorable
Long seems to be either a 32 or 64 bit integer - use int or long here
Stop is just a break statement

So overall the code looks a little like this

//Don't know how to declare the Draw() function
void CallBox(int aFunctionCall)
{
    //I'm not certain if the array bound specifier looks like this
    char[255] *msg;

    if(aFunctionCall == -1)
    {
        GetErrorMessage(msg);
        //Print the message some other way here
        break;
    }
}

char[255] *GetStr(long aBoxHandle, long aPropId)
{
    char[255] *result;

    CallBox(GetStrProp(aBoxHandle, aPropId, result));
    return result;
}

Re: VBasic to VC++ syntax conversion

Software20079-Mar-09 14:51

Software2007

9-Mar-09 14:51

Good starting point.

Thanks

sft

Application Type - DLL

su_penguin9-Mar-09 10:59

su_penguin

9-Mar-09 10:59

Hello all,

After installing the Visual C++ Express Edition, I've noticed that the Win32 Application Wizard does not allow you to create a DLL as the Application Type. Is there any way around this?

Thanks

Re: Application Type - DLL

su_penguin9-Mar-09 11:03

su_penguin

9-Mar-09 11:03

Just so anyone doesn't think I've posted a Yes or No question: How can I get around this?

Re: Application Type - DLL

su_penguin9-Mar-09 11:40

su_penguin

9-Mar-09 11:40

http://social.msdn.microsoft.com/Forums/en-US/Vsexpressvc/thread/6d37e2d1-7491-450f-a341-a81e7892dce1/

Found it!

Re: Application Type - DLL

Iain Clarke, Warrior Programmer10-Mar-09 1:30

Iain Clarke, Warrior Programmer

10-Mar-09 1:30

Glad you've found the solution. My answer was going to be "spend money"!

Iain.

Codeproject MVP for C++, I can't believe it's for my lounge posts...

Issue with localtime()

Member 38480949-Mar-09 10:53

Member 3848094

9-Mar-09 10:53

I would be very grateful for any constructive comments to the snippet of code below:

time_t lTime
struct tm *tm

time(&lTime)
tm = localtime(&lTime)

It is found that tm->tm_hour agrees with my PC time except between the following dates when it is 1 hour behind:

8 Mar, 2009 2:00 am
15 Mar, 2009 2:00 am

I believe the issue is in TZSET.c and only manifests itself when the day of the 1st of the month of DST is a Sunday (like 2009).

I am using VS6 and have applied KB932509 with no results

Thanks

Peter

Yusuf9-Mar-09 11:12

Yusuf

9-Mar-09 11:12

Member 3848094 wrote:
KB932509

I can't get this on MS site? what is the KB about.

Yusuf

Oh didn't you notice, analogous to square roots, they recently introduced rectangular, circular, and diamond roots to determine the size of the corresponding shapes when given the area. Luc Pattyn[^]

Member 38480949-Mar-09 11:18

Member 3848094

9-Mar-09 11:18

Sorry, my mistake

KB932590

Thanks

Yusuf9-Mar-09 11:23

Yusuf

9-Mar-09 11:23

well, did you check your file version against what is listed on that KB?

Member 38480949-Mar-09 11:39

Member 3848094

9-Mar-09 11:39

Yes.

Do you believe that this download should have fixed the issue?

Yusuf9-Mar-09 13:42

Yusuf

9-Mar-09 13:42

I don't know. What else do you think it would do then?

Another thing you can check is, run dependency walker (or whatever it is called) and check the dll version you application using. I doubt this will turn anything, but you got nothing to loose.