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I have been developing C++ code for many years now, but I am relatively new to MFC. I am going through the book "Programming Windows 95 with MFC" (First Edition) by Jeff Prosise. I have carefully gone through the first seven characters of the book. I also went through all the examples and ran them on my computer with no problems. I have also written three toy MFC applications.
When I get to chapter 8 (which deals with SDI), I cannot get the example to work. I feel that MFC programs written using the SDI model are hard to understand and hard to debug. I do not see the SDI model as a big time saver for the developer. Is it really that good? By the way, if somebody has a small (say under 100 lines) MFC SDI program that they could send me, I would really appreciate it.
The reason I am learning MFC is that I want to write a 1st class Retirement Calculator. Should such a program be written as a SDI application? I am thinking that it should not.
Please comment.
Bob
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The book you've got is really good for learning MFC.
The question I have is: what version of visual studio are you using to run the examples? I found it easy to compile the examples with VC++ 6.0. I think that the newer versions of VC++ will work but you might get some problems.
As far as the need for SDI and MDI applications: you can usually get by just using dialog based apps. However, the SDI apps provide a better design framework. This is especially true if you want to distribute your presentation code from you data handling code. The SDI framework also makes it easy to save your application's data.
One thing that might help you is to try deriving the View class from CFormView. This has the effect of combining the SDI Document/View framework with the ease of Dialog programming. (The App wizard allows you to change the View base class in the last step.)
Good luck
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Can someone give me a example of a assignment statement to compute wages?
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I am going to assume that the person's rate is in the variable rate and that the number of hours
worked is in a varaiable called hours. In addition, I am assuming time and a half after 40.
pay = rate*hours + ( (hours>40) ? (rate*hours/2) : 0 );
Now, there is an issue about the type of the variables. Should they be an integer type or a floating point type. There is also the related issue of rounding. I hope this helps.
Bob
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So if he hours worked is 40, pay rate is 12.75 and the weekly wages = 510. would the assignment statement be:
weekly wages = pay rate*hours worked + ( (hours>;40) ? (12.75*hours/2) : 0 );
Does this make sense.
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You added an extra semicolon, but the statement does make sense. It should be:
weekly wages = 12.75*40 + ( (40>40) ? (12.75*40/2) : 0 );
Now, 12.75*40 = 510 and 40 > 40 is false so we have
weekly wages = 510 + 0
or
weekly wages = 510
Bob
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Last question. Before the statement does it have to be declared?
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I am not sure I understand your question. However, all variables must be declared/defined before use. If you use a variable without declaring it, the compiler will generate a compiler error.
Bob
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I'm sorry for being confusing. Does the assignment statement goes in as a statement like:
//weekly wages = 12.75*40 + ( (40>40) ? (12.75*40/2) : 0 );
modified on Thursday, October 16, 2008 8:53 PM
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It depends on exactly what you want to compute, however, in a word, No. If Weekly wages is suppose to be a variable then you are not allowed to have spaces in the variable.
I get the impression that I am not helping you. I think you need to find a basic tutorail on C or C++ and read it.
Bob
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Bob you helped me out alot. I have a better understanding of what I was doing wrong. Thanks for the help.
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Hi,
I am using API RegEnumValue() to retrieve the regkey's values. However, for DWORD and BINARY datatype it returns some garbage or junk characters in buffer(for the values which has above datatypes).. do I need to typecast this returned data to make it readable in eng ??? if yes how shud I do that, any pointers ?
Thanks in advance.
Regards,
Supriya Tonape
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Please give us an example of the input (i.e. the registry key type & value), the code you're using and the output you're getting.
BTW ALL the info inside any PC has to be translated in some manner in order to read it as English.
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
[My articles]
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The Registry Key Value Type is 'REG_DWORD' and 'REG_BINARY'.
You can create any new key in registry and then create new key values for it which has datatype as above(Selecting 'DWORD Value' and 'BINARY Value') and plz have a look at datavalue to see how data looks like.. For 'REG_SZ' values I am getting data in buffer properly.
Sample Code : (Assume regkey handle and open proc is passing and I am able to access it thru another APIs)
// Enumerate the key values.
if (dwValues)
{
.
.
for (i=0, retCode=ERROR_SUCCESS; i<dwvalues;>
{
.
.
retCode = RegEnumValue(
hkScanKey, // Handle to an open registry key
i, // The index of the value to be retrieved
pszRegValueName, // Pointer to a buffer that receives the name of the value
&dwRegValNameLen, // Size of the buffer pointed to by the 'pszRegValueName'
NULL, // Reserved
&dwRegValType, // Type of data
(LPBYTE)pszRegValData, // Data for the value
&dwRegValLen); // Size of Data
.
.
}
}
so whenever it finds any value with datatype 'REG_DWORD' or 'REG_BINARY' , the buffer 'pszRegValData' has some garbage value or unreadble val...
Regards,
Supriya Tonape
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Are you aware that RegEnumValue returns a 32 bit integer whenever it finds a REG_DWORD? It doesn't return the string representation of the number. The same applies to REG_BINARY. Of course I'm only guessing, since you missed posting input & output value samples.
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
[My articles]
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RegEnumValue returns data in 'BYTE' in one of the OUT parameters and yes it does return the LONG value for the function call.
I am talking about 'lpData' param in below structure.
LONG WINAPI RegEnumValue(
__in HKEY hKey,
__in DWORD dwIndex,
__out LPTSTR lpValueName,
__inout LPDWORD lpcchValueName,
__reserved LPDWORD lpReserved,
__out_opt LPDWORD lpType,
__out_opt LPBYTE lpData,
__inout_opt LPDWORD lpcbData
);
when I iterate thru different values of regkey I get below outputs:
'REG_DWORD' Data : "94f"
lpData = ''
(For 'REG_SZ' datatype its does return proper output)
'REG_SZ' Data : "|386|ADE|ADP"
lpData = '|386|ADE|ADP'
Regards,
Supriya Tonape
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Supriya Tonape wrote: 'REG_DWORD' Data : "94f"
lpData = ''
In the above circumstance, with
DWORD dwValue = *((DWORD *) lpData);
what is the value of dwValue?
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
[My articles]
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Thank you so much! it did help and I didnt want REG_BINARY conversion anymore but yes for REG_DWORD your help is much appreciated !
Regards,
Supriya Tonape
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You're welcome.
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
[My articles]
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I am new to this. I have made an activex edit control that deals only with floating point numbers. It works perfect in the test container, but I cannot get it to work at all in my application. After inserting it the software added the class to my project. It compiles without error or warning, but I cannot update data to the control or read anything frrom it into my application. Any advice would be appreciated.
Thanks
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Just because there wasn't a clear / working link to an old MSDN article that got archived, rewritten, and (insert w/e they do at m$ web oversight here),
http://msdn.microsoft.com/en-us/library/kdzttdcb.aspx[^]
WaitForSingleObject works with beginthreadex because it doesn't close its own handle
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Indeed!
There's several differences described in the current docs[^]
(see the Remarks section).
Mark
Mark Salsbery
Microsoft MVP - Visual C++
![Java | [Coffee]](https://codeproject.freetls.fastly.net/script/Forums/Images/coffee.gif)
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Below is what is suppose to be a valid but minimal MFC Application using SDI. It consists of
two files, the first is a header file, the second is a C++ file.
Header File
#define IDR_MAINFRAME 100
class MainApp : public CWinApp {
public:
virtual BOOL InitInstance();
};
C++ File
#include <afxwin.h>
#include "Main.h"
#define OEMRESOURCE
MainApp myApp;
class MyDocument : public CDocument {
DECLARE_DYNCREATE( MyDocument )
};
IMPLEMENT_DYNCREATE( MyDocument, CDocument )
class MyView : public CView {
DECLARE_DYNCREATE( MyView )
protected:
void OnDraw(CDC *);
};
IMPLEMENT_DYNCREATE( MyView, CView )
void
MyView::OnDraw(CDC *pDC)
{
}
BOOL
MainApp::InitInstance ()
{
SetRegistryKey (TEXT("Programming Windows 95 with MFC"));
LoadStdProfileSettings ();
CSingleDocTemplate* pDocTemplate;
pDocTemplate = new CSingleDocTemplate (
IDR_MAINFRAME,
RUNTIME_CLASS (CDocument),
RUNTIME_CLASS (CFrameWnd),
RUNTIME_CLASS (MyView)
);
AddDocTemplate (pDocTemplate);
RegisterShellFileTypes (TRUE);
CCommandLineInfo cmdInfo;
ParseCommandLine (cmdInfo);
if (!ProcessShellCommand (cmdInfo))
return FALSE;
m_pMainWnd->DragAcceptFiles ();
return TRUE;
}
However, when I compile and run it, it dies in the call to DragAcceptFiles. I do not understand why. I am hoping that somebody here can tell me what is wrong, or the best way to debug this program.
Thanks
Bob
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BobInNJ wrote: it dies in the call to DragAcceptFiles
Hello Bob, when you are experiencing errors saying things like "it doesn't work","it breaks","it dies" is not appropriate. You need to post actual error information. GetLastError() numbers, Exception text, assert information like the line of code containing the assert, etc. Hopefully you get the idea.
BobInNJ wrote: or the best way to debug this program.
I don't know what that means. Debugging is somewhat universal, you break into the execution at a line of code and analyze the state of the process using debugger tools (call stack, memory values).
Also, in case you are trying to implement drop files without a net maybe this will help.[^]
led mike
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Thank you for the response. The error message I get is in the form of a Error Box. The title
of the Box says Microsoft Visaul C++ Debug Library". It also has the line Debug Assertion Failed!. The box also has button on it for Abort, Retry and Ignore.
It gets to the statement:
if (!ProcessShellCommand (cmdInfo))
but it does not get to the statement:
m_pMainWnd->DragAcceptFiles ();
Therefore, I step into the routine ProcessShellCommand. Here is the call stack for the
program after it dies:
> sdi1.exe!AfxMessageBox(unsigned int nIDPrompt=61700, unsigned int nType=0, unsigned int nIDHelp=4294967295) Line 163 + 0x17 bytes C++
sdi1.exe!CSingleDocTemplate::OpenDocumentFile(const wchar_t * lpszPathName=0x00000000, int bMakeVisible=1) Line 113 C++
sdi1.exe!CDocManager::OnFileNew() Line 848 C++
sdi1.exe!CWinApp::OnFileNew() Line 22 C++
sdi1.exe!CWinApp::ProcessShellCommand(CCommandLineInfo & rCmdInfo={...}) Line 26 C++
sdi1.exe!MainApp::InitInstance() Line 46 + 0xc bytes C++
sdi1.exe!AfxWinMain(HINSTANCE__ * hInstance=0x00400000, HINSTANCE__ * hPrevInstance=0x00000000, wchar_t * lpCmdLine=0x00020908, int nCmdShow=1) Line 37 + 0xd bytes C++
sdi1.exe!wWinMain(HINSTANCE__ * hInstance=0x00400000, HINSTANCE__ * hPrevInstance=0x00000000, wchar_t * lpCmdLine=0x00020908, int nCmdShow=1) Line 30 C++
sdi1.exe!__tmainCRTStartup() Line 263 + 0x2c bytes C
sdi1.exe!wWinMainCRTStartup() Line 182 C
kernel32.dll!7c817067()
[Frames below may be incorrect and/or missing, no symbols loaded for kernel32.dll]
Also, it would seem to me that this is a very simple MFC program and that for somebody who understands MFC should be able to tell me what is wrong off the top of his (or her) head. Maybe, I am wrong about this. My limited experience with MFC SDI programs is that they are full of unexpected surprises.
Thanks
Bob
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