C / C++ / MFC

16-Aug-02 3:11

b::b will be called. You don't need the cast. You'd need the cast if you'd derive b using private/protected inheritance.

Tomasz Sowinski -- http://www.shooltz.com

Never argue with an idiot, he'll bring you to his level and beat you with experience.

Re: C++ Gurus

Raskolnikov17-Aug-02 6:14

Raskolnikov

17-Aug-02 6:14

As mentioned this is perfectly leagal and often usefull, especially in conjuction with virtual functions.

[James Pullicino] wrote:
Which constructor will be called?

The answer is both. b's constructor is called which then imediately calls a's.

class a<br />
{<br />
public:<br />
	a() {cout << "A's Constructor\n";}<br />
};<br />
<br />
class b : public a<br />
{<br />
public:<br />
	b() {cout << "B's Constructor\n";}<br />
}

If you are in doubt about some feature it is always a good idea to use print statements or better yet step through the code with a debugger. Posting your question on a message board is also a good idea. Smile | :)

Display Hexadecimal

Rsh16-Aug-02 2:33

Rsh

16-Aug-02 2:33

i have an unsigned char array which has certain data. I want that data of the array to be displayed in hexadecimal format in CListCtrl. For ex. if i have ch[0]=0x10,it should be displayed as 10 in the list control. can anybody help?
Here is my code, but it displays l in the list control.
******************************
unsigned char DataMsg[32];
LV_ITEM lvitem;
CString dataText= (CString)DataMsg[0];
lvitem.mask = LVIF_TEXT | 0;
lvitem.iItem = iItem;
lvitem.iSubItem = 0;
pStrTemp1= dataText.GetBuffer(dataText.GetLength());
lvitem.pszText = pStrTemp1;
m_listCntrl.InsertItem(&lvitem);
***********************************

Rsh

Re: Display Hexadecimal

Christian Graus16-Aug-02 3:00

Christian Graus

16-Aug-02 3:00

You could use an ostringstream and I think the modifier is hex() to make it display as hex.

Christian

We're just observing the seasonal migration from VB to VC. Most of these birds will be killed by predators or will die of hunger. Only the best will survive - Tomasz Sowinski 29-07-2002 ( on the number of newbie posters in the VC forum )

Cats, and most other animals apart from mad cows can write fully functional vb code. - Simon Walton - 6-Aug-2002

Re: Display Hexadecimal

Tomasz Sowinski16-Aug-02 3:47

Combo box being clipped by parent

16-Aug-02 3:47

Use CString::Format with %x or %X

Tomasz Sowinski -- http://www.shooltz.com

Never argue with an idiot, he'll bring you to his level and beat you with experience.

ReX16-Aug-02 2:26

ReX

16-Aug-02 2:26

Hello,
I have created a CDialog. Inside it I have put a CComboBox and have added items to it. Whats happening is that when i click the drop down arrow it clips the drop list inside the dialog only showing the number of items that will fit above the bottom of the dialog. Is it possible to get it not to clip the droplist within the dialog ?

Thanks ReX

Re: Combo box being clipped by parent

Tomasz Sowinski16-Aug-02 3:12

Re: Combo box being clipped by parent

16-Aug-02 3:12

Dialog shouldn't clip the dropdown part of combo. Make sure that dropdown rectangle is big enough - click on dropdown arrow in resource editor and adjust the rectangle height.

Tomasz Sowinski -- http://www.shooltz.com

Never argue with an idiot, he'll bring you to his level and beat you with experience.

ReX16-Aug-02 4:33

ReX

16-Aug-02 4:33

The size of the dropdown rectangle is correct adjusted in the resource editor. If I size the dialog bigger, the the full dropdown list is shown (because dialog bottom is far enough) Confused | :confused:

ReX

Re: Combo box being clipped by parent

Tomasz Sowinski16-Aug-02 4:47

16-Aug-02 4:47

Strange. I've never seen this behavior. Are you doing dirty tricks with subclassing the dropdown part?

Tomasz Sowinski -- http://www.shooltz.com

Never argue with an idiot, he'll bring you to his level and beat you with experience.

std:string

Shamoon16-Aug-02 2:03

Shamoon

16-Aug-02 2:03

I want to replace the last character of a string represented by std::string with comma. How can i do so ??

Example:

std::string mystring("Hellow World");

I want to replace last character of "Hellow World" i.e 'd' by comma "'"

ReX16-Aug-02 2:23

ReX

16-Aug-02 2:23

I wrote this function for this purpose. I hope this helps.

inline void Replace(std::string* pstr, const char old_char, char* pnew_char)
{
if(!pstr->empty())
{
int n = 0;
while((n = pstr->find(old_char)) != -1)
{
*pstr = pstr->erase(n, 1);
*pstr = pstr->insert(n, pnew_char);
}
}
}

Usage:

Replace(&mystring, 'd', ',');

For the last character only you can take:

mystring.erase(mystring.length(), 1);
mystring.append(',');

Greetings ReX

Mike Nordell17-Aug-02 23:36

17-Aug-02 23:36

That's also a way to burn CPU cycles. Another (possibly better) way to do it could be
std::replace(string.begin(), string.end(), 'a', 'b');
to replace all instances of 'a' with 'b'.

mishgun16-Aug-02 2:26

mishgun

16-Aug-02 2:26

*mystring.rbegin() = '.';

it works Smile | :)

nobody is perfect

Mike Nordell17-Aug-02 23:30

17-Aug-02 23:30

Isn't that to be *(++mystring.rbegin()) = '.'; ?

mishgun18-Aug-02 11:48

mishgun

18-Aug-02 11:48

nope

rbegin() returns last member of container, as i understand it Smile | :)

))

nobody is perfect

Mike Nordell19-Aug-02 1:14

Please help. How do i use acmFormatEnum?

19-Aug-02 1:14

Then, AFAIK, your understanding is wrong. The doc's I've seen says "The rbegin member function returns a reverse iterator that points just beyond the end of the controlled sequence" and every experience I have with rbegin() says the same.

redeemer16-Aug-02 1:45

redeemer

16-Aug-02 1:45

I'm trying to enumerate all the different formats for a specific format type, but every time i run the acmFormatEnum function it returns MMSYSERR_INVALPARAM meaning "At least one parameter is invalid.". Anyone know how to use that function? Anyone have some examples? All help is greatly appreciated, here's my code. I start by running the TagEnum function:

ACMFORMATTAGDETAILS acmTagDetails;

void TagEnum()
{
	HACMDRIVER hAcm;

	acmDriverOpen(&hAcm, id, 0);
	
	acmTagDetails.cbStruct = sizeof(ACMFORMATTAGDETAILS);
	acmFormatTagEnum(hAcm, &acmTagDetails, acmTagCallback, NULL, 0);

	acmDriverClose(hAcm, 0);
}


BOOL WINAPI acmTagCallback(HACMDRIVERID hadid, LPACMFORMATTAGDETAILS paftd, DWORD dwInstance,DWORD fdwSupport)
{
	ACMFORMATDETAILS acmFormat;
	WAVEFORMATEX waveFormat = { 0 };
	HACMDRIVER hAcm;

	memset(&acmFormat, 0, sizeof(acmFormat));
	acmFormat.cbStruct = sizeof(acmFormat);
	acmFormat.cbwfx = sizeof(waveFormat);
	acmFormat.pwfx = &waveFormat;
	acmFormat.dwFormatTag = acmTagDetails.dwFormatTag;

	waveFormat.wFormatTag = acmTagDetails.dwFormatTag;

	acmDriverOpen(&hAcm, hadid, 0);
	acmFormatEnum(hAcm, &acmFormat, formatCallback, NULL, ACM_FORMATENUMF_WFORMATTAG);
	acmDriverClose(hAcm, 0);

	return TRUE;
}

BOOL WINAPI formatCallback(HACMDRIVERID hadid, LPACMFORMATDETAILS pafd, DWORD dwInstance, DWORD fdwSupport)
{
	ACMDRIVERDETAILS details;

	details.cbStruct = sizeof(details);

	acmDriverDetails(hadid, &details, NULL);

	SendMessage(GetDlgItem(ghWnd, IDC_FORMATS), LB_INSERTSTRING, 0, (LPARAM)details.szLongName);

	return TRUE;
}

id is a HACMDRIVERID holding a valid driver id of a driver. Anyone have a clue what could be wrong or have some examples?

All help is apprecaited.

-Rune Svendsen

Re: Please help. How do i use acmFormatEnum?

Mike Nordell18-Aug-02 0:40