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Hello;

I'm in trouble with CListCtrl. I've creating a CListCtrl object at runtime without any problem on CView. But problem appearing when i want to use GetItemData()method. Object has returning 0 value for each item. But i have set item data for each item with following code;

CListCtrl* m_box = reinterpret_cast<clistctrl*>(this->GetDlgItem(IDC_LIST_JOBVIEW));

while(SQL_NO_DATA!=SQLFetch(hstmt)) {
m_sdk.StrTrim(reinterpret_cast<unsigned char*="">(plugin));
m_box->InsertItem(i, plugin, (DWORD)atoi(pcstat));
m_box->SetItemData(i, id);
i++;
}

But, int f = m_box->GetItemData(2); return 0.

What is the problem? Any scope problem?
Thank you...

Ahmet Orkun GEDiK

Is your list sorted?

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

"Yields falsehood when preceded by its quotation" yields falsehood when preceded by its quotation.

Short answer, no. Smile | :)

Ahmet Orkun GEDiK

What is id?

Is it a local variable. I'm assuming it is a pointer, but are you deleting it before you call to GetItemData?

Michael Smile | :)

Time flies like an arrow. Fruit flies like a banana

No. I know, it's local variable. But i have created the object on heap with new keyword. i didn't delete the pointer.

<br />
CListCtrl* m_box = reinterpret_cast<CListCtrl*>(this->GetDlgItem(IDC_LIST_JOBVIEW));<br />
.<br />
.<br />
.<br />
	i=0;<br />
	while(SQL_NO_DATA!=SQLFetch(hstmt))	{<br />
		m_sdk.StrTrim(reinterpret_cast<unsigned char*>(plugin));<br />
		m_box->InsertItem(i, plugin, (DWORD)atoi(pcstat));<br />
		m_box->SetItemData(i, id); <br />
		i++;<br />
	}<br />
	int f = m_box->GetItemData(2);<br />

as a result, damn! f=0;
Something strange!!!

Ahmet Orkun GEDiK

Yipe!!!
I've found the solution. SetItemData has a bug i guess. It doesn't set mask to LVIF_PARAM of item which makes problem.

Isn't strange???
Smile | :)

Ahmet Orkun GEDiK

Hi!

I generated a custom class derived from CTreeCtrl which contains tree items with different iIntegrals. The tree can't calculate the correct height which causes a problem with vertical scrolling: I can't scroll to the end of the tree - the last items are not accessible by scrolling...
Anyone an idea how to manage this problem?

Thnx!

How can I have a splash screen in VC6?

Mazy

"If I go crazy then will you still
Call me Superman
If I’m alive and well, will you be
There holding my hand
I’ll keep you by my side with
My superhuman might
Kryptonite"Kryptonite-3 Doors Down

There's one in VC++ built-in component gallery.

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

"Yields falsehood when preceded by its quotation" yields falsehood when preceded by its quotation.

Here are two articles

www.codeproject.com/dialog/dialogspl.asp

www.codeproject.com/dialog/splasher.asp

If you insist in finding evil in me you will find it, whether it is there or not.

Hi,

I created a CListCtrl in CView Class as follows:

<br />
m_ctrlMesgList->Create(WS_CHILD | WS_VISIBLE | WS_BORDER | LVS_ALIGNLEFT |<br />
			LVS_REPORT , rect, this, 1);<br />

How do I add a vertical scroll bar to this CListCtrl??
adding WS_VSCROLL to Create(...) is not working Frown | :(

Thanx in advance...

List control displays a vertical scrollbar only if needed, e.g. when there's enough items in list to make scrolling necessary.

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

"Yields falsehood when preceded by its quotation" yields falsehood when preceded by its quotation.

try EnableScrollBar(SB_VERT); + ShowScrollBar(SB_VERT);

<

Please describe me step-by-step.

As it happens, the full code for an mp3 player is here on CP, but it's listed under mpeg instead of mp3. Search for skinnable mpeg and you'll find it.

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

MS DirectX SDK 8 has a built-in MP3 decoder,

And I swallow a small raisin.

Winamp is open source, also, and have developer forums.
http://www.winamp.com/nsdn
Might get some info there, also.

BW
{insert witty/thought-provoking saying here}

Hi All,

Can anyone please explain me on how to write a variable(integer type) into the registry and also how to read it back

Thanks
Uday

Check the API function with names starting with Reg prefix, like RegSetValueEx. If you're using MFC, you can also use CWinApp::WriteProfileXXX methods.

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

"Yields falsehood when preceded by its quotation" yields falsehood when preceded by its quotation.

Following code isn't perfect but it works and should get you started. If you look at the documentation for RegSetValueEx() you can set the dwType param to REG_DWORD for numbers but I usually just deal with strings and use atoi() or similar to convert.

bool bGetRegistryEntry(const HKEY hKey, const char* name, unsigned char* const dest)
{
bool bReturnVal = true;
unsigned long lType = 0;
unsigned long ulSize = MAX_PATH;

if (ERROR_SUCCESS != RegQueryValueEx(hKey, name, NULL, &lType, dest, &ulSize))
{
bReturnVal = false;
}

return (bReturnVal);
}

bool bSetRegistryEntry(const HKEY hKey, const char* name, unsigned char const* dest)
{
bool bReturnVal = true;
unsigned long lType = 0;
LONG lRESULT = 0;

lRESULT = RegSetValueEx(hKey, name, 0, REG_SZ, dest, _mbslen(dest) + 1);
//ERROR_ACCESS_DENIED indicates it already exists
if ((lRESULT != ERROR_SUCCESS) && (lRESULT != ERROR_ACCESS_DENIED))
{
bReturnVal = false;
}
return (bReturnVal);
}

// Open or create registry.
void vRegOpenKey()
{
HKEY hKey=0;
//char *my_App = "Registry_Example";
CString sAppId = "SOFTWARE\\RegKeyExample";
bool bReturnVal = false;
DWORD dwDisposition = 0;

if (ERROR_SUCCESS != RegOpenKeyEx(HKEY_LOCAL_MACHINE, sAppId, 0, KEY_READ, &hKey))
{

LONG lRESULT = 0;
lRESULT = RegCreateKeyEx(HKEY_LOCAL_MACHINE,
sAppId,
0,
REG_NONE,
REG_OPTION_NON_VOLATILE,
KEY_ALL_ACCESS,
NULL,
&hKey,
&dwDisposition);
if (lRESULT != ERROR_SUCCESS)
{
MessageBox(NULL, "Registry not available!", NULL, NULL);
return;

}
}

const unsigned char name[5] = "this";
if (!bSetRegistryEntry(hKey, "value1", &name[0]))
{
MessageBox(NULL, "Unable to set registry value1", NULL, NULL);
}
else
{
unsigned char name2[5];
if (bGetRegistryEntry(hKey, "value1", name2))
{
CString sText;
sText.Format("Registry value1 is %s", name2);
MessageBox(NULL, sText, NULL, NULL);
}
else
{
MessageBox(NULL, "Unable to get registry value1", NULL, NULL);
}
}

RegCloseKey( hKey );

}

Excuse the lengthy post : but I've been getting quite frustrated researching this topic, and I'd like to get someones informed advice if possible.

I have written an MFC app, using OpenGL to provide my own custom 3D model editor. I am using the CDocument/View architecture and everything is fine.

Now I want to code plugins for tools that manipulate the data in the model.

Having spent a few days researching on the web, I come to the following conclusions :

1) DLL's should be fairly straightforward to use
2) No two sources agree on how they should be done
3) Microsoft don't help matters.

:S

This is what I want to do :-

a) Create a "tool" class that plugs into the main app (ie. CPluginExtrude).

b) The main app then checks its plugins directory on loading, for any .dll's present, installs them, and attaches them to the CMainFrame menu so that the user can invoke them.

c) The plugin is given a pointer (on initialisation) to the CDocument derived model, and the main app so that it has full access to the application and its data.

d) When a plugin is invoked, it may simply perform it's function on the model data, or it may invoke a dialog asking for parameters beforehand.

e) It is vital that I can create plugins as and when, without the necessity to recompile/rebuild the main application.

I have coded a partial plugin implementation - which works upto the pointer where I attempt to use GetProcAddress to find a function pointer by its name, this always returns null, even though the function I am trying to obtain has been declared with __declspec (dllexport) in the plugin .dll

I am using VC6, and the W2K MFC dll's

Having rattled off all of that, if someone can supply a link to a site that explains all (which I have as yet been unable to find Frown | :(

) then that would be great...

Thanks in advance!

(PS : I may provide the results of my research & solution as an article somewhere - possibly gamedev - and full credit will be given Wink | ;)

)

makom42 wrote:
which works upto the pointer where I attempt to use GetProcAddress to find a function pointer by its name, this always returns null, even though the function I am trying to obtain has been declared with __declspec (dllexport) in the plugin .dll

The trick is to use both extern "C" and __cdecl - this way your function name won't be mangled by the compiler and you'll easily get the pointer:

extern "C" __declspec(dllexport) 
void __cdecl ZoopaDoopa(CRuntimeClass *&pViewClass, CRuntimeClass *&pFrameClass)
{
...
}

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

"Yields falsehood when preceded by its quotation" yields falsehood when preceded by its quotation.

Already being done...

I am convinced this is something stupid somewhere... a missing macro definition or something... thanks anyway Tomasz Big Grin | :-D

1) Check plugin dll with depends.exe. Right click on .dll icon in the Windows Explored and select 'View dependencies'. You'll see the list of functions exported from your .dll. Ensure that function names aren't mangled - they shouldn't contain @ characters and letters/digits appended by compiler

2) If you're absolutely sure that plugin exports the functions, check the GetProcAddress side. Ensure that function name isn't misspelled. Check the HMODULE you're passing to GetProcAddress. If it still fails, call GetLastError() and post result here.

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

"Yields falsehood when preceded by its quotation" yields falsehood when preceded by its quotation.