C / C++ / MFC

Re: Owner Draw ListBox not recognising tab commands in strings

3-Dec-09 3:02

maycockt wrote:
...even when configuring LBS_USETABSTOPS.

Did you send the control a LB_SETTABSTOPS message?

"One man's wage rise is another man's price increase." - Harold Wilson

"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

maycockt3-Dec-09 3:32

Re: Owner Draw ListBox not recognising tab commands in strings

3-Dec-09 3:32

Hi,

I hadn't sent a LB_SETTABSTOPS message, but I had used SetTabStops funtion, which had no effect.

In my OnInitDialog I have tried the following......

<per>
m_plbMyControl = new CCustomListBox();

if(NULL != m_plbMyControl )
{
CRect rList(10, 10, 580, 285);
DWORD dwStyle = LBS_NOTIFY | LBS_OWNERDRAWVARIABLE | LBS_NOINTEGRALHEIGHT | LBS_HASSTRINGS | LBS_USETABSTOPS | WS_BORDER | WS_HSCROLL;

if(TRUE == m_plbMyControl->Create(dwStyle, rList, this, IDC_LIST_CONTROL))
{
//m_plbMyControl->SetTabStops(16);
::SendMessage(m_plbMyControl->m_hWnd, LB_SETTABSTOPS, (WPARAM)1, (LPARAM)16);
}
}

Whereas the SetTabStops call had no effect, the ::SendMessage just gets an unhandled exception.
I am sure the SetTabStops or LB_SETTABSTOPS is the right way to go, I just cant seem to work out how to use it properly!!!

Any further help would be much appreciated.

TIA

Tony

David Crow3-Dec-09 3:39

Re: Owner Draw ListBox not recognising tab commands in strings [modified]

3-Dec-09 3:39

maycockt wrote:
//m_plbMyControl->SetTabStops(16);
::SendMessage(m_plbMyControl->m_hWnd, LB_SETTABSTOPS, (WPARAM)1, (LPARAM)16);

Just to see if the tabstops are even being used, have you played around with other values besides 16? Four character units does not seem large enough to separate anything but very small (1-2 characters) words.

maycockt3-Dec-09 3:57

Re: Owner Draw ListBox not recognising tab commands in strings

3-Dec-09 3:57

Hi,

I've tried 0, 1, 4, 8, 16........
Each time using ::SendMessage it crashes with an Unhandled Exception.

TIA

Tony

modified on Thursday, December 3, 2009 10:06 AM

David Crow3-Dec-09 4:13

Re: Owner Draw ListBox not recognising tab commands in strings [modified]

3-Dec-09 4:13

maycockt wrote:
I've tried 0, 1, 4, 8, 16........

(I think) You need to use larger values, not smaller.

maycockt3-Dec-09 4:21

Re: Owner Draw ListBox not recognising tab commands in strings

3-Dec-09 4:21

A value of 16 should give 4 display units I believe, so bigger than that would cause larger gaps in my spacing?

I don't understand why the ::SendMessage is failing though, each time it falls over in the first ::CallWidnowProc of DefWindowProc, i.e. m_pfnSuper is valid.

I can use a WPARAM of 0, and a LPARAM of NULL and it doesnt fail, but the ListBox still ignores TabStops.....

I'm beginning to think a redesign using a list control and hidden HeaderCtrl might be the way to go........

Tony

modified on Thursday, December 3, 2009 10:45 AM

David Crow3-Dec-09 5:41

Re: Owner Draw ListBox not recognising tab commands in strings

3-Dec-09 5:41

maycockt wrote:
A value of 16 should give 4 display units I believe, so bigger than that would cause larger gaps in my spacing?

Yes, of course. The intent was to see if the tabstops were even working. At this point, you don't know if the tabstops are just not large enough, or if the LBS_USETABSTOPS style is being ignored, or if the LB_SETTABSTOPS message is wrong.

maycockt3-Dec-09 5:48

Re: Owner Draw ListBox not recognising tab commands in strings

3-Dec-09 5:48

Hi David,

That probably was more blunt than I intended. I was more sort of querying that my understanding was correct of the dimensions.

The LBS_USERTABSTOPS I would guess is being ignored, probably because of one of the other settings.

Incidentally, would SetTabStops(16) have the same effect as the SendMessage()?

I would have thought it should.

Thanks for your help so far

Tony

David Crow3-Dec-09 5:55

Re: Owner Draw ListBox not recognising tab commands in strings

3-Dec-09 5:55

maycockt wrote:
The LBS_USERTABSTOPS I would guess is being ignored, probably because of one of the other settings.

That's easy enough to test. Create a non-ownerdraw listbox, and call AddString() to add the strings to it. If that works, then the problem likely has to do with the LBS_OWNERDRAWVARIABLE style.

maycockt wrote:
Incidentally, would SetTabStops(16) have the same effect as the SendMessage()?

Yes. The former is just a convenient wrapper around the latter.

maycockt3-Dec-09 6:05

Re: Owner Draw ListBox not recognising tab commands in strings

3-Dec-09 6:05

Having removed the LBS_OWNERDRAWVARIABLE the formatting is using the tabs appropriately, but with that I am back to square 1 of needing to intercept the drawing as I need to have some of the text emboldened.

Do you think then that my style settings must be wrong?

I currently rule out and include in the PreCreateWindow as follows

<per>
// Turn off disallowed styles
cs.style &= ~( LBS_SORT |
LBS_OWNERDRAWFIXED |
LBS_MULTICOLUMN);
// Turn on mandatory styles
cs.style |= ( LBS_NOTIFY |
LBS_HASSTRINGS |
LBS_OWNERDRAWVARIABLE |
LBS_NOINTEGRALHEIGHT |
LBS_USETABSTOPS |
WS_BORDER );

Anything I am missing?

Tony

David Crow3-Dec-09 6:22

Re: Owner Draw ListBox not recognising tab commands in strings

3-Dec-09 6:22

Are you calling TextOut() in the CCustomListBox::DrawItem() method? If so, try calling TabbedTextOut() instead. Also, the call to SetTabStops() seems to be unnecessary.

maycockt6-Dec-09 20:38

Re: Owner Draw ListBox not recognising tab commands in strings

6-Dec-09 20:38

Hi David,

Thanks for your help.
TabbedTextOut was the solution to achieve what I wanted. I'm still a bit confused why LB_USETABSTOPS wasnt working, but hey ho - we have what the moeny men want now.

Thanks again

Tony

raymondc05-Dec-09 12:03

raymondc0

5-Dec-09 12:03

Um, it's owner-draw. You're the one doing the drawing. If it's not drawing the way you want, then fix your drawing code.

Re: Owner Draw ListBox not recognising tab commands in strings

maycockt6-Dec-09 20:41

Re: Owner Draw ListBox not recognising tab commands in strings

6-Dec-09 20:41

Thanks for your wonderful pearls of wisdom.

It must be nice to know everything and never be in need of asking a question, especially when helpful suggestions made don't bear fruition.

I had an issue, I asked a question, and someone was kind enough to work with me to get a result. Is that not what these forums are about?

raymondc07-Dec-09 4:09

raymondc0

7-Dec-09 4:09

Sorry, I thought I was being helpful: You have an owner-draw listbox. Therefore, you are doing the drawing. If it's not drawing the way you want, then you need to look more carefully at your drawing code. Since you didn't post your drawing code, it's not clear what further assistance was possible.

Re: Owner Draw ListBox not recognising tab commands in strings

David Crow3-Dec-09 5:52

Re: Owner Draw ListBox not recognising tab commands in strings

3-Dec-09 5:52

I doubt it's part of the problem, but is there any reason why you are creating a heap-based CCustomListBox object?

maycockt3-Dec-09 5:56

3-Dec-09 5:56

Hi David,

The answer to that question is that my DIalog design wasn't working, and I was wondering whether it was to do with creation etc, and I didnt go back to it yet.
As I'm getting the same results as with my original design, I will go back to it.

Either way, the tab stops dont seem to want to work Frown | :(

Tony

mysql_fetch_field

MsmVc3-Dec-09 0:38

MsmVc

3-Dec-09 0:38

Hello All
I getting exception while I use

mysql_fetch_field

.I use debug then I found when table rows is more than 229000 then Iam getting exception in this line

field1=mysql_fetch_field(res1);

Unhandled exception at 0x10010d74 in SQLconvert.exe: 0xC0000005: Access violation reading location 0x00000040.

Call stack shows

libmySQL.dll!10010d74() 	
 	[Frames below may be incorrect and/or missing, no symbols loaded for libmySQL.dll]	
>	SQLconvert.exe!CSQLconvertDlg::EnumRow(ATL::CStringT<char,StrTraitMFC<char,ATL::ChTraitsCRT<char> > > tab="sheet1")  Line 1400 + 0xc bytes	C++
 	SQLconvert.exe!CSQLconvertDlg::Convert()  Line 1147	C++
 	SQLconvert.exe!readThread(void * p=0x0012f254)  Line 56	C++
 	SQLconvert.exe!_AfxThreadEntry(void * pParam=0x0012e5c0)  Line 109 + 0xf bytes	C++
 	SQLconvert.exe!_callthreadstartex()  Line 348 + 0xf bytes	C
 	SQLconvert.exe!_threadstartex(void * ptd=0x003fd628)  Line 331	C
 	kernel32.dll!7c80b699()

code is here

QueryResultsPtr Qry;
MYSQL_FIELD	*field1;
MYSQL_RES	*res;
enum enum_field_types type;
	if (!mysql_query(conn," SELECT * FROM tes")) 
	{
		res = mysql_store_result(conn) ;
		int numrows = (int)mysql_num_rows(res);
		int numflds = (int)mysql_num_fields(res);
		
		while (row = mysql_fetch_row(res)) 
		{
			
			res1=mysql_list_fields(conn,tab,"%");
			for(long y=0; y<numflds; y++)
			{
				
				str2.Empty();
				field1=mysql_fetch_field(res1);
				if(field1->flags & AUTO_INCREMENT_FLAG)
					continue;
				str2+=(LPTSTR)row[y];
				type=field1->type;
				
			}
}
}

includeh103-Dec-09 1:26

includeh10

3-Dec-09 1:26

It may be a bug, but I don't think that you need to SELECT * from the huge table, why do not where something to reduce fetched rows?

try to use mysql_use_result() rather than mysql_store_result() to see if the problem can be fixed.

BTW: mysql_num_rows() is invalid if using mysql_use_result().

Rajesh R Subramanian3-Dec-09 1:26

Rajesh R Subramanian

3-Dec-09 1:26

MsmVc wrote:
int numrows = (int)mysql_num_rows(res);

res is an uninitialised pointer and is probably pointing to some random memory location. If mysql_num_rows() attempts to write anything to the memory pointed by res, the Universe will end.

Why can't you try this instead?

MYSQL-RES res;
...//bunch of stuff
mysql_num_rows(res);

That applies to other pointer variables as well.

“Follow your bliss.” – Joseph Campbell

MsmVc3-Dec-09 1:30

MsmVc

3-Dec-09 1:30

sorry

res is an initialised Globel MYSQL_RES *res;

Rajesh R Subramanian3-Dec-09 1:33

Rajesh R Subramanian

3-Dec-09 1:33

MsmVc wrote:
res is an initialised Globel MYSQL_RES *res;

The results will still be the same, won't it be? I do not know if the method that accepts that particular pointer will do a write operation to it, or probably call some method on it if it's a class object.

Either ways, how do you expect an uninitialised pointer to work? Confused | :confused:

Try creating the variable on the stack and use it instead.

“Follow your bliss.” – Joseph Campbell

MsmVc3-Dec-09 1:40

MsmVc

3-Dec-09 1:40

sir
my code is working fine when table rows is less than 229000.I am getting error when table rows is more than 229000.
So there is no need to discusses about res is an initialised or uninitialised.Matter is why

mysql_fetch_field(res1);

generating exception if table rows is more than 229000.
Plz help me