C / C++ / MFC Discussion Boards

paresh_joe13-Sep-07 21:02

13-Sep-07 21:02

i am using Dialog based MFC application.
simple application i have create is add new node in Tree-view as text specified in edit box.

now problem is that when i am adding i dont want duplicated node being added to Tree-view.
i should get reference to already existing node when i try to add node with same text.

Help needed : how to search node in tree-view ..
Rose | [Rose]

Re: Search node in TreeView

nbugalia13-Sep-07 21:23

nbugalia

13-Sep-07 21:23

You can use HTREEITEM hKid = GetChildItem (hParent); in a loop to get all the children of a parent, but the better idea is to maintain a array of nodes or labels that are already added in the tree.
You can search in the array to check if this node or label is already added.

If you want to check the labels, then it's always good to use CMapStringToString class, as you can directely check if the string is there or not. (In array, you have to search the whole array to find if item is there or not)

Re: Search node in TreeView

Nishad S13-Sep-07 21:28

Nishad S

13-Sep-07 21:28

You have to search the node using GetNextItem. It will return the HTREEITEM. If the text is same, you can call SetItemState for that node

- NS -

Re: Search node in TreeView

paresh_joe13-Sep-07 21:32

paresh_joe

13-Sep-07 21:32

Thank you ...

i am sooo Sniff | :^)

that no direct function available ....

Connection Error

Programm3r13-Sep-07 20:37

Programm3r

13-Sep-07 20:37

Hi all,

I'm trying to connect to an Oracle database, with the following function:

...
	ret = SQLConnect(m_hDbc, 
					(SQLCHAR*)szDSN, 
					strlen(szDSN), 
					(SQLCHAR*)szUser, 
					strlen(szUser),
					(SQLCHAR*)szPass, 
					strlen(szPass));
...

But I keep recieving the following error:

[Microsoft][ODBC driver for Oracle][Oracle]ORA-12154: TNS:could not resolve the connect identifier specified

I have added the entry to the tnsnames.ora file, and checked the "tnsping" using TNS service name, which worked.

Can anyone please help?
Many Thanks in advacne

Regards,

The only programmers that are better that C programmers are those who code in 1's and 0's Green Alien | [Alien]

Programm3r
My Blog: ^_^

Re: Connection Error

p_13-Sep-07 23:35

13-Sep-07 23:35

hi try this code to connect to oracle

SAConnection con; // connection object
SACommand cmd; // command object
{
con.Connect("test", "tester", "tester", SA_Oracle_Client);
cmd.setConnection(&con);
}

How to get the byte order of a computer?

kcynic13-Sep-07 20:01

kcynic

13-Sep-07 20:01

I want to know a computer's byte order.
Somebody would like to tell me how to get the order?
Thanks.

GOOD LUCK.

Re: How to get the byte order of a computer?

Azteke13-Sep-07 20:06

Azteke

13-Sep-07 20:06

It depends on your CPU. I believe most (if not all) PCs are Little-Endian, meaning (going off memory here) that the bytes are ordered, within a word, with the least significant byte first. You can google "Endian-ness" for a more complete and correct answer.

Re: How to get the byte order of a computer?

kcynic13-Sep-07 22:23

kcynic

13-Sep-07 22:23

OK,I will go and have a look.
Thanks.

Re: How to get the byte order of a computer?

Maxwell Chen13-Sep-07 22:32

Maxwell Chen

13-Sep-07 22:32

Endianness[^]

Maxwell Chen

Re: How to get the byte order of a computer?

David Crow14-Sep-07 3:22

David Crow

14-Sep-07 3:22

Maxwell Chen wrote:
Endianness[^]

Were you afraid that kcynic would not be able to Google the suggestion from Azteke correctly?

"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: How to get the byte order of a computer? [modified]

kakan13-Sep-07 20:48

kakan

13-Sep-07 20:48

One way to do it. I'm not sure if it works on 64-bits CPU's though.
Remark (before I get flamed): Yes, it is old C code.

Detection of Little- and Big-endian:

bool bIsLittleEndian = false;
unsigned int test = 0x12345678;
unsigned char firstByte = *(unsigned char *) &test;

if(firstByte == 0x78) bIsLittleEndian = true;

Detection of Little-, Middle and Big-endian:

enum {LITTLE_ENDIAN, MIDDLE_ENDIAN, BIG_ENDIAN};

int endian;
unsigned int test = 0x12345678;
unsigned char firstByte = *(unsigned char *) &test;

if(firstByte == 0x78) endian = LITTLE_ENDIAN;
else if(firstByte == 0x34) endian = MIDDLE_ENDIAN;
else endian = BIG_ENDIAN;

-- modified at 5:38 Friday 14th September, 2007
Maxwell Chen made me aware there are such a thing as Middle-endian, so I made another sample. (Middle-endian is appearantly used in some PDAs and mobile phones that is using CPU's with ARM architecture.)

Alcohol. The cause of, and the solution to, all of life's problems - Homer Simpson

Re: How to get the byte order of a computer?

Maxwell Chen13-Sep-07 22:30

Maxwell Chen

13-Sep-07 22:30

There is also the "Middle-endian"[^] as well. :->

Maxwell Chen

Re: How to get the byte order of a computer?

kakan13-Sep-07 23:28

kakan

13-Sep-07 23:28

Thanks for the comment.
I will change my reply, since it could be fatal to execute my code on a PDP 11 machine. Laugh | :laugh:

OK, it seems as some PDAs and mobile phones uses CPU's with ARM architecture. That scenario seems a bit more likely. I will change my reply accordingly.
Thaks for pointing it out.

Alcohol. The cause of, and the solution to, all of life's problems - Homer Simpson

Re: How to get the byte order of a computer?

Azteke14-Sep-07 18:10

Azteke

14-Sep-07 18:10

Kakan,

That's interesting, I never though of using code to determine the Endian=Ness. I'll remember that.

Azteke

Reading microphone input

Azteke13-Sep-07 19:35

Azteke

13-Sep-07 19:35

Hi, I'm working on a project where I need to do the following:

1) Constantly (at some defined rate that approximates "constant") sample the microphone input.
2) Take the input that is read and determine the frequency of the tone being input.

If it's possible, number 2 would run on each execution cycle. The idea is to have a big if-block that performs different logic depending on what range the frequency is in.

What I need is an API (and a document to help explain it would be helpful) that will allow me to do this sampling/frequency determination. I'm new to PC programming for the most part, coming from about a year and a half of embedded (fairly basic) development, but I'm excited to start learning! I do know the basics of MFC apps/dialogs and I have VS2005 Professional at my disposal.

The one last thing is that I would like this to run on Linux also eventually so if there's a good API that is cross-platform that would be ideal if it doesn't add too much trouble.

Much appreciated,
Tim

Re: Reading microphone input

Russell^'13-Sep-07 22:04

Russell^'

13-Sep-07 22:04

1) you can use sleeep function, or better, ose a timer to be alerted after a specified time

2) To do this take a look at these articles:

http://www.codeproject.com/audio/wave_class_for_playing_and_recording.asp[^]

http://www.codeproject.com/useritems/julienT.asp[^]

http://www.codeproject.com/audio/oscilloscope.asp[^]

Russell

Re: Reading microphone input

Azteke14-Sep-07 18:12

Azteke

14-Sep-07 18:12

Ressell, after a quick scan-through I think that third link is exactly what I need. Thanks. Does anyone know of a cross platform API though for future Linux ports?

Thanks,
Tim

Re: Reading microphone input

Russell^'14-Sep-07 22:25

Russell^'

14-Sep-07 22:25

Thanks

About Linux:
I don't know anything about it to help you, sorry.

You can start a new thread,...but think also to post it in another forum: here more than 90% of members are expert on Windows. I don't want to mean that here noone can help you, but that it is not so impossible.

good luck
Rose | [Rose]

Russell

Reg. Structure variable [modified]

rajaratk13-Sep-07 19:22

rajaratk

13-Sep-07 19:22

Hello,

Good Day!

Step 1:

struct user
{

unsigned short us_nbs;
unsigned short us_debit;
unsigned short us_flowctrl;
};

Step 2:

In another header file contains this:

"class C_User : public CObject, public user"

Step 3:

class C_Subscriber : public C_User

Step 4:
C_Subscriber subdeviceSubs = *lpSubscr;

Step 5:
I got that us_flowctrl value is "0" by executing this statement : subdeviceSubs.us_flowctrl. How?

Thanks in advance
Raja Ratheesh

-- modified at 1:56 Friday 14th September, 2007

Re: Reg. Structure variable

Nishad S13-Sep-07 20:23

Nishad S

13-Sep-07 20:23

rajaratk wrote:
C_Subscriber subdeviceSubs = *lpSubscr;

What is this lpSubscr?

- NS -

Re: Reg. Structure variable

rajaratk13-Sep-07 22:47

rajaratk

13-Sep-07 22:47

Instance of

typedef struct user far *LPUSER;

Re: Reg. Structure variable

Nishad S14-Sep-07 1:44

Nishad S

14-Sep-07 1:44

So you are getting values changed...

class C_User : public CObject, public user
class C_Subscriber : public C_User
typedef struct user far *LPUSER

C_Subscriber subdeviceSubs = *lpSubscr;

So the C_Subscriber has CObject in the first memory area. I doubt that it could be the problem.

Dont you get any compilation error by "C_Subscriber subdeviceSubs = *lpSubscr;" ?

- NS -

Tab Order

msr_codeproject13-Sep-07 17:10

msr_codeproject

13-Sep-07 17:10

Hi friends........

I have a question on tab oreder.......?

How the tab order will effect the visibility of controls placed on a dialog?

Thank u in advance.....

Sairam Madem

Re: Tab Order

Mark Salsbery13-Sep-07 18:07

Mark Salsbery

13-Sep-07 18:07

The WS_VISIBLE style effects the visibility of controls on a dialog.

If you meant the Z-order, the controls are created in the order they
appear in the DIALOG resource, so initially, the first control will be at the
bottom of the z-order, the last control at the top.

Setting the tab order sets the order of the control definitions in the resource.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

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