C / C++ / MFC

25-Sep-09 8:58

Hello

I am working on an Up-Down spin control which is used to update values in
a text control.

The range of values are from 20 to -20.

What i have seen is, if i click the UP or DOWN arrow and keep it
pressed, then somehow after counting 15 it will stop decrementing or inceremting.

i.e., if the current value is 20 and now am clicking the DOWN button and keep
it pressed, the text control value will decrement upto 5, and then will stop there.

Now i have to release the mouse button and then again click the DOWN arrow to further decrement.
Now again after 15 decrements it will stop decrementing and i have to release the
mouse and click again.

Any idea why this happening?

David Crow25-Sep-09 9:08

25-Sep-09 9:08

dipuks wrote:
I am working on an Up-Down spin control which is used to update values in
a text control.

Are you referring to an msctls_updown32 control? If you are using MFC, do you have a CSpinButtonCtrl object associated with it?

dipuks wrote:
The range of values are from 20 to -20.

How did you set this range?

I just tried this and it works fine for me.

"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

dipuks25-Sep-09 9:25

25-Sep-09 9:25

Are you referring to an msctls_updown32 control?

YES

If you are using MFC, do you have a CSpinButtonCtrl object associated with it?

I am not using MFC, am working using Win32 API's

David Crow25-Sep-09 9:28

25-Sep-09 9:28

dipuks wrote:
I am not using MFC, am working using Win32 API's

So then are you sending the control a UDM_SETRANGE message?

dipuks25-Sep-09 9:37

25-Sep-09 9:37

Yes UDM_SETRANGE32

Am using all 32 bit messages,

UDM_SETPOS32, UDM_GETPOS32,...

in UDM_DELTAPOS i try to update the value in text control

David Crow25-Sep-09 9:41

25-Sep-09 9:41

dipuks wrote:
UDM_SETPOS32, UDM_GETPOS32,...

in UDM_DELTAPOS i try to update the value in text control

By default, these are not necessary. Assuming the up/down control comes right after the edit control in the Z-order, do you have the UDS_AUTOBUDDY and UDS_SETBUDDYINT styles set?

dipuks25-Sep-09 9:48

25-Sep-09 9:48

Rules for what you can/can't do inside DOC class serialization(loading) routine

Rolf Kristensen26-Sep-09 7:39

Rolf Kristensen

26-Sep-09 7:39

Maybe this can help: CNumSpinCtrl - a simple numeric spin control[^]

al250025-Sep-09 6:27

al2500

25-Sep-09 6:27

Hi all,

I have a MDI document which has to load an ascii file into a collection class on File-Open, preferably before serialization of the classes that I load using the standard CArchive serialization since those elements are dependent on the collection class. In other words my code looks like this -

void CMyDoc::Serialize(CArchive& ar)
{

if (ar.IsStoring())
	{.....

else {

CFile ChartFile;
  if (!ChartFile.Open(m_DataPathName, CFile::modeRead)){
	return FALSE;
   }

  CArchive archive(&ChartFile, CArchive::load);

  while (archive.ReadString(FileData) != NULL){

   //misc code to format ascii data

   m_MyCArray.Add();

 ar >> MyVar1
    >> MyVar2
    >> ....
}

It's all working now but the code to read the ascii file originally read some variables from the DOC class and also wrote some to the DOC class. Here is what happened before I removed that code -

1. I would get random exceptions on accesses to the variables in the doc class (sometimes they would happen, sometimes not) when exercising the File-Open menu.

2. Any Doc class variable that was set from inside this routine would be garbage after it completed.

The odd thing about this is that the container class m_MyCArray is valid after exiting this routine. Perhaps it's because m_MyCArray is instantiated (indirectly) in the Doc class while I accessed the other Doc variables with a pointer to the doc class (because the ascii file read routine is actually a seperate module instantiated in the doc class - to complex to show above).

I got this idea from an example in Jeff Prosise's book so presumably it's valid but I think there were some timing issues with my code. Perhaps the new doc class is still being initialized or is initialized after the completion of serialization. Mike Blaszczak's book has some info on how a new doc comes to life but he does not say anything about serialization in this regard.

As I said, after removing all pointer based accesses to the doc class everything seems to work fine but it would be nice to understand what state the doc class is in at the time of serialiazation or what happens afterward.

Thanks

Re: Rules for what you can/can't do inside DOC class serialization(loading) routine

Iain Clarke, Warrior Programmer25-Sep-09 21:21

Iain Clarke, Warrior Programmer

25-Sep-09 21:21

I don't actually trust the serialisation of MFC all that much - it looks fine for trivial things, but it doesn't take a lot before it fails, or is not flexible enough.

I have a few questions...

You say about doc variables being valid in another routine, but that's hidden with a comment - we can't help you a lot there.

Do you make sure you clear all your doc variables in the constructor so they're valid but... boring... ?

Where does the file name m_DataPathName come from? It's not from the opening process? But as the Serialize function is called during CDocuments auto loading process, which include constructing the CDocument, ehen do you set it?

Iain.

I have now moved to Sweden for love (awwww).
If you're in Scandinavia and want an MVP on the payroll (or happy with a remote worker), or need cotract work done, give me a job! http://cv.imcsoft.co.uk/[^]

Function does not return String as wanted

Tomicmanka25-Sep-09 6:26

25-Sep-09 6:26

Hi Guys,

I am pretty new to C++. And would require your help.

I am trying to get surname into a string using getline(cin,surName) and then passing it to a function to convert the string to upper case. Please note that I know there are functions available to do the conversion but I am trying to learn passing / returning "string" from a function.

Thanks in Advance
Tomic

char* conv_str_to_upper (char* str_io)
{
int stringlength = strlen(str_io);
for (int i=0; i

markkuk25-Sep-09 7:05

markkuk

25-Sep-09 7:05

A C++ string isn't a char*. You can't apply old C char* based methods to handling C++ strings.

David Crow25-Sep-09 7:51

25-Sep-09 7:51

Tomicmanka wrote:
for (int i=0; i str_io[i] = std::toupper(str_io[i]);

Did you bother to preview this before posting?

Tomicmanka wrote:
conv_str_to_upper (surName);

Is conv_str_to_upper() going to know what to do with a string object?

Tomicmanka wrote:
free (pstrText);

What are you freeing?

Go back and edit your post so that it is: 1) syntactically correct, and 2) easier to read.

Tomicmanka25-Sep-09 8:47

25-Sep-09 8:47

Sorry mate, The text "free (pstrText);" was part of a larger program.

As I said I am very new (I have benn working on C++ for the last one week) so just bear with me.

I just want to know how to write a c++ function that accepts a string as parameter and return a string back to the main() function.

At this moment in time I want to convert a lowercase Surname to uppercase using a C++ function.

char* conv_str_to_upper (char* str_io)
{
int stringlength = strlen(str_io);

for (int i=0; i
str_io[i] = std::toupper(str_io[i]);
}
return (str_io);
}

The code above may be wrong, I just want to know how it can be done.

Thanks

David Crow25-Sep-09 8:57

25-Sep-09 8:57

Tomicmanka wrote:
I just want to know how to write a c++ function that accepts a string as parameter and return a string back to the main() function.

string foo1( string str )
{
    string strTemp;
    strTemp = str;
    return strTemp;
}
  
void foo2( string &str )
{
    str = ...
}

Tomicmanka wrote:

At this moment in time I want to convert a lowercase Surname to uppercase using a C++ function.

Use the transform() function. See here

Tomicmanka25-Sep-09 9:28

25-Sep-09 9:28

Thanks David

My code now works

Stuart Dootson26-Sep-09 0:07

Stuart Dootson

26-Sep-09 0:07

Tomicmanka wrote:
I just want to know how to write a c++ function that accepts a string as parameter and return a string back to the main() function.

Rather than passing a string by value, you should generally prefer passing a string by reference to minimise copying.

std::string conv_str_to_upper (std::string const& str)
{
   std::string upper;
   // Tell upper how long it's going to end up being, so we can allocate that space all at once
   upper.reserve(str.length());
   // Copy s to upper, but upper-case each character as we go.
   std::transform(s.begin(), s.end(), std::back_inserter(upper), (int (*)(int))&std::toupper);
   return upper;
}

The code for the function is taken from this page[^], which is kind of on your topic.

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

Tomicmanka26-Sep-09 0:55