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I finally got it to work - I changed everything around to separate the implementations from the declaration and the compiler finally started giving me some better messages ('name' : dependent name is not a type) So it turned out that I just needed to throw a couple 'typename' keywords in there. I've never heard of that before... *sigh* Maybe I should stick to C#.
Anyway, here's the working code:
#pragma once
#include <assert.h>
// Declaration:
template <class T>
class LinkedList
{
public:
class Enumerator;
LinkedList();
LinkedList(const LinkedList<T> &objectToCopy);
virtual ~LinkedList();
virtual T GetItem(int index);
virtual int GetCount();
virtual void Add(T value);
virtual void Insert(int index, T value);
virtual void RemoveAt(int index);
virtual Enumerator GetEnumerator();
protected:
struct ListNode;
ListNode *_head;
int _count;
virtual ListNode *AddressOf(int index);
};
template <class T>
struct LinkedList<T>::ListNode
{
T Item;
ListNode* Next;
};
template <class T>
class LinkedList<T>::Enumerator
{
friend Enumerator LinkedList<T>::GetEnumerator();
public:
virtual T GetCurrent();
virtual bool MoveNext();
virtual void Reset();
protected:
LinkedList<T> *_linkedList;
ListNode *_current;
Enumerator();
};
//Implementation:
template <class T>
T LinkedList<T>::Enumerator::GetCurrent()
{
return _current->Item;
}
template <class T>
bool LinkedList<T>::Enumerator::MoveNext()
{
if (_current == 0)
_current = _linkedList->_head;
else
_current = _current->Next;
return _current != 0;
}
template <class T>
void LinkedList<T>::Enumerator::Reset()
{
_current = 0;
}
template <class T>
LinkedList<T>::Enumerator::Enumerator() : _current(0)
{
}
template <class T>
LinkedList<T>::LinkedList() : _count(0), _head(0)
{
}
template <class T>
LinkedList<T>::LinkedList(const LinkedList<T> &objectToCopy) : _count(objectToCopy._count)
{
if (objectToCopy._head == 0)
_head = 0;
else
{
_head = new ListNode;
_head->Item = objectToCopy._head->Item;
ListNode *newestNode = _head;
for (ListNode *nodeToCopy = objectToCopy._head->Next; nodeToCopy != 0; nodeToCopy = nodeToCopy->Next)
{
newestNode->Next = new ListNode;
newestNode = newestNode->Next;
newestNode->Item = nodeToCopy->Item;
}
newestNode->Next = 0;
}
}
template <class T>
LinkedList<T>::~LinkedList()
{
while (_count > 0)
RemoveAt(0);
}
template <class T>
T LinkedList<T>::GetItem(int index)
{
return (AddressOf(index))->Item;
}
template <class T>
int LinkedList<T>::GetCount()
{
return _count;
}
template <class T>
void LinkedList<T>::Add(T value)
{
Insert(_count, value);
}
template <class T>
void LinkedList<T>::Insert(int index, T value)
{
assert(index >= 0 && index <= _count);
ListNode *nodeToInsert = new ListNode;
nodeToInsert->Item = value;
nodeToInsert->Next = AddressOf(index);
if (index == 0)
_head = nodeToInsert;
else
(AddressOf(index - 1))->Next = nodeToInsert;
_count++;
}
template <class T>
void LinkedList<T>::RemoveAt(int index)
{
assert(index >= 0 && index <= _count - 1);
ListNode *nodeToRemove = AddressOf(index);
if (index == 0)
_head = _head->Next;
else
(AddressOf(index - 1))->Next = (AddressOf(index + 1));
_count--;
delete nodeToRemove;
}
template <class T>
typename LinkedList<T>::Enumerator LinkedList<T>::GetEnumerator()
{
Enumerator newEnumerator;
newEnumerator._linkedList = this;
return newEnumerator;
}
template <class T>
typename LinkedList<T>::ListNode *LinkedList<T>::AddressOf(int index)
{
if (index < 0 || index > _count - 1)
return 0;
else
{
ListNode *node = _head;
for (int i = 0; i < index; i++)
node = node->Next;
return node;
}
}
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Not bad at all! I think you over use ‘virtual’, as this is essentially a container type that you would not normally derive from and those methods (other than destructor) would not normally be overridden.
It is a good idea to keep your C++ skills well oiled, shortly after C# first came onto the seen, there where calls for programmers to convert C# code to C++. There should always be a demand for people with good C and C++ skills in addition to the other languages they may know.
The ability to write good templates is a plus and is one area of C++ where you will learn the most about C++.
Reinvent the wheel or anything else that increases your understanding of the language or programming in general. Some programmers rewrite their favorite piece of code in every new language they learn, so that they can get a better understanding of it.
Have fun and Good luck! 
INTP
"Program testing can be used to show the presence of bugs, but never to show their absence."Edsger Dijkstra
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OK, so I'm writing a program that basically locks down the computer. One of the necessary components of this is to disable the alt key, but I can't use a keyhook/DLL, etc., anything external. Intercepting WM_SYSKEY or anything like that doesn't work since most function calls are on a higher level. I can successfully block alt+tab, ctrl+alt+dlt, but not alt+spacebar.
So, what I'm using is scancode mapper to assign the alt key(s) to a null value (in other words, they won't function at all). But, upon changing these registry values, I must restart. I need this to be an almost instanteneous change though.
How can I employ this registry change without going throught the restart process? Would I have to reload keyboard drivers, and if so, how do I do that? I have been researching and googling all over the place, but I've found nothing useful. Please help.
Thanks, sjm96
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I have a CMultiDocTemplate application (Doc/View Arc), I have Open multiple documents in the application, I would like to move a specific document with a particular path name to the top of the rest of the documents that is open.
I was able to find that PathName of the open document with this routine:
POSITION template_pos = AfxGetApp()->GetFirstDocTemplatePosition();
while(NULL!=template_pos)
{
CDocTemplate* pDocTemplate = AfxGetApp()->GetNextDocTemplate(template_pos);
if(NULL!=pDocTemplate)
{
POSITION document_pos = pDocTemplate->GetFirstDocPosition();
while(NULL!=document_pos)
{
CDocument* pDoc_to_check = pDocTemplate->GetNextDoc(document_pos);
AfxMessageBox(pDoc_to_check->GetPathName());
}
}
}
But I would like to move it to the top. How can I do that?
Thanks,
Chien
-- modified at 19:50 Wednesday 4th April, 2007
BTW, There is a similar solution in this site, called WindowsManager (OnActivate), however, the solution is too complicated and it does not make use of the Path name.
-- modified at 20:29 Wednesday 4th April, 2007
OK, I guess I can use the Windows Manager solution provided by Ivan Zhakov in http://www.codeproject.com/docview/windowsmanager.asp BUT I need to be able to store the full path name instead of just the window title
void CWindowDlg::FillWindowList(void)
{
m_wndList.SetRedraw(FALSE);
m_wndList.ResetContent();
HWND hwndT;
hwndT=::GetWindow(m_pMDIFrame->m_hWndMDIClient, GW_CHILD);
while (hwndT != NULL)
{
TCHAR szWndTitle[256];
::GetWindowText(hwndT,szWndTitle,sizeof(szWndTitle)/sizeof(szWndTitle[0]));
int index=m_wndList.AddString(szWndTitle);
m_wndList.SetItemData(index,(DWORD) hwndT);
hwndT=::GetWindow(hwndT,GW_HWNDNEXT);
}
m_wndList.SetRedraw(TRUE);
}
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I am new to window enviroment and I would like to know how I can display grayscale image using visual c++ 6.0?
snowcone
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Hello,
You need to use Win32 along GDI functions like this:
CreateWindow()
GetDC()
SelectObject()
GetStockObject()
SetStretchBltMode()
SetPixel()
StretchBlt()
BitBlt()
…
DeleteDC()
DeleteObject()
etc.
Regards,
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Since I am too new to window visualC++, I am not quite following your flow here. Can you give me code example that I can compile and run in visualc++ to load an grayscale image and display it on window frame?
Thanks.
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Try searching for bitmaps on codeproject.
Peter
"Until the invention of the computer, the machine gun was the device that enabled humans to make the most mistakes in the smallest amount of time."
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of course you can use of SetPixelRGB with two loops for height and width but its not good idea better use of BitBlt and see last parameter of BitBlt on the MSDN
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I have written software that talks to various GPIB instruments. Since most of the instruments are Agilent (old HP), I am using their instrument drivers and everything is working just fine.
My question is this..... Is there some some software out there that I can use to scan the GPIB buss to see what instruments are actually connected or not? Maybe even something that I can modify to fit my specific needs????
Thanks in advance
Pierre
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Hello,
Just try: NI Measurement & Automation Explorer->Devices and Interfaces->GPIB0. Now right click and choose 'Scan for Instruments' menu.
Regards,
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Thank you very much....
But, I was looking for something that I can write into my own code
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Does anyone know of a way to display file sizes larger than 2GB as a string?
I need to display the disk space remaining, but ULARGE_INTEGER, ULONGLONG,__int64 don't have a / operator, so "X / 1GB" won't comPile
Want to show results as: "2.65GB"
Thanks!
-- modified at 15:02 Wednesday 4th April, 2007
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Wes Jones wrote: but ULARGE_INTEGER, ULONGLONG,__int64 don't have a / operator
On what compiler?
This works for me...
__int64 llGigaBytes = 1073741824LL * 4LL;
llGigaBytes = llGigaBytes / 1073741824LL;
Here's how I display memory in my app "About..." dialogs:
double GigaBytes = (double)MemoryStatEx.ullTotalPhys / (double)1073741824.00;
_stprintf(szOutText,TEXT("%.2f GB (%I64d Bytes)"), GigaBytes, MemoryStatEx.ullTotalPhys);
Mark
"If you can dodge a wrench, you can dodge a ball."
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Thanks for the reply, & Sorry I forgot to mention it already, I'm using VC6.0
The line:
double GigaBytes = (double)pMyULARGE->QuadPart / (double)1073741824.00
results in compiler error:
conversion from unsigned __int64 to double not implemented, use signed __int64
I changed my mind & I figured that my app will probably never have worry about running into the signed/unsigned boundary on a 64bit number when displaying file sizes or disk space, so I just cast the ULARGE_INTEGER::QuadPart to LONGLONG & it now works.
In case somebody else is looking for this, I'll post my down & dirty function:
CString FormatSize(PULARGE_INTEGER pul)
{
ASSERT( pul );
const ULONG n1MB = 1024 * 1024;
const ULONG n1GB = n1MB * 1024;
CString str;
if( pul->QuadPart == 0 )
str = _T("0 KB");
else
if( pul->QuadPart < (n1MB) )
str.Format(_T("%.2lf KB"), pul->LowPart / 1024.0);
else
if( pul->QuadPart < n1GB )
str.Format(_T("%.2lf MB"),
((double) ((LONGLONG)pul->QuadPart) / ((double n1MB) ));
else
str.Format(_T("%.2lf GB"),
((double) ((LONGLONG) pul->QuadPart) / ((double)n1GB)));
return str;
}
Thanks!
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Wes Jones wrote: ...so "X / 1GB" won't comfile
What "comfiler" error do you get?
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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 You use VC6 right? Is __int64 not a built-in type on that compiler?
Mark
"If you can dodge a wrench, you can dodge a ball."
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Nothing special needs to be done in order to use it, if that's what you are asking.
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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Then do you know why the code I posted won't compile (according to the OP)?
I'm on VS2003.
ACK I meant "comfile"...
"If you can dodge a wrench, you can dodge a ball."
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Because he did not heed the compiler:
double GigaBytes = (double) ((__int64) MemoryStatEx.ullTotalPhys) / 1073741824.00;
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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That's what I figured. Just wanted to know for future reference.
Thanks man!
Mark
"If you can dodge a wrench, you can dodge a ball."
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Man, sometimes I wonder about the people here... 
Have you looked into StrFormatByteSize64(...)?
Peace!
-=- James Please rate this message - let me know if I helped or not!<HR>If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
See DeleteFXPFiles
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StrFormatByteSize64 isn't defined in the SDK on my machine for one reason or another.
Thanks for the pointer tho!
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Your SDK and/or your MSDN Library is severely out of date - this function is available for use with VC++ 6.0, so even the last version of MSDN Library that integrates with it (which is a few years old) has it.
Note that this function became available with IE 5.0, so you need to have the _WIN32_IE value #defined to 0x0500 or greater for it to become visible. Lookup that identifier/macro if you do not know how to set it correctly.
Peace!
-=- James Please rate this message - let me know if I helped or not!<HR>If you think it costs a lot to do it right, just wait until you find out how much it costs to do it wrong!
Avoid driving a vehicle taller than you and remember that Professional Driver on Closed Course does not mean your Dumb Ass on a Public Road!
See DeleteFXPFiles
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James R. Twine wrote: Man, sometimes I wonder about the people here...
Yeah whatever. So I'm the last one that hasn't memorized all the APIs.
Thanks for that. I know I'll forget it later but I'll remember its existence!
Tidbits like that are the only reason I'm here
Peace!
Mark
"If you can dodge a wrench, you can dodge a ball."
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