Cell blink for DataGridView

After reading many articles on Code project, I realized that it's my time to contribute. Few months ago, I came across a requirement for cells in a DataGridView control to blink when the cell value changed. The code presented here can be applied to any other grid.

The blinking of the grid cell is achieved in the following manner. When we update the value of a cell, we also change the background color of that cell to a blink color. To restore the cell background color to its original value, we run a background thread that iterates through a list of cells that are blinking and resets them to their original non blinking state.

The code
The sample project has two functions. The first function DataInputThreadFunc() is used to generate random values to be filled / updated in the grid. The second function GridBlinkThreadFunc() is used to restore the cells to the non blink state.

Let's take a look at the first function DataInputThreadFunc():

Collapseprivate void DataInputThreadFunc()
{
Random rand = new Random();
while (true)
{
if (dataGridView1.IsDisposed)
break;

CellData data = new CellData();
data.Row = rand.Next(0, 7);
data.Col = rand.Next(0, 3);
data.Time = DateTime.Now;

int value = rand.Next(0, 101);

dataGridView1.Invoke((MethodInvoker)delegate()
{
dataGridView1.Rows[data.Row].Cells[data.Col].Value = value;
dataGridView1.Rows[data.Row].Cells[data.Col].Style
.BackColor = Color.Salmon;
});

lock (_blinkData)
{
_blinkData.Add(data);
}

Thread.Sleep(1000);
}
}


The function uses a while (true) loop as it's a background thread and will be shutdown automatically when the application is closed. if (dataGridView1.IsDisposed) check is done to make sure we do not call dataGridView1.Invoke() on a disposed object. This can happen when the user closes the application.

Next, we initialize an object of the class CellData to store the blink data.

class CellData
{
public int Row;
public int Col;
public DateTime Time;
}

This class is used to store the row number, column number and the time when the value changed.

Next we use dataGridView1.Invoke() to make a call to the user interface thread and set the grid properties. We save the blink data in a generic list to be used later by the blink thread function. Since the list is altered by more than one thread, we synchronize access by locking the list on each access.

Now let's take a look at the blink thread function.

Collapseprivate void GridBlinkThreadFunc()
{
while (true)
{
// Make a copy to avoid invalid operation exception
// while iterating through the map
List tempBlinkData;
lock (_blinkData)
{
tempBlinkData = new List(_blinkData);
}

foreach (CellData data in tempBlinkData)
{
TimeSpan elapsed = DateTime.Now - data.Time;
if (elapsed.TotalMilliseconds > 500) // 500 is the Blink delay
{
if (dataGridView1.IsDisposed)
return;

dataGridView1.BeginInvoke((MethodInvoker)delegate()
{
dataGridView1.Rows[data.Row].Cells[data.Col]
.Style.BackColor = dataGridView1.Columns[data.Col]
.DefaultCellStyle.BackColor;
});

lock (_blinkData)
{
_blinkData.Remove(data);
}
}
}

Thread.Sleep(250); // Blink frequency
}
}

At the very beginning, we make a copy of the _blinkData list. This helps us to modify the list while we iterate through the contents of the temporary copy. For each cell we find in the list, we check to make sure whether the blink time has elapsed or not. In this case the blink time is 500 milliseconds. Any cell that has elapsed the blink time gets its background color reset to the default cell style background color and is removed from the list.

Again we make sure that we set the grid property only in the user interface thread. In addition, we lock the _blinkData list before altering it. Thread.Sleep(250) is the frequency with which we go through the list to turn off the cells. Ideally, it should be half the value of blink delay.

Points of Interest
You will notice this code can be applied to any grid. This code can also be hidden in a class that extends a DataGridView control.

One thing I love about .NET 2.0 is this dataGridView1.Invoke((MethodInvoker)delegate(). This statement lets you get away from writing a function and declaring a delegate. That frees up tons of browsing time!

A good point was made by "Kristof Verbiest" about the use of BeginInvoke() instead of Invoke(). The GridBlinkThreadFunc() uses BeginInvoke() to avoid unnecessary context switch.

A Class to Save and Load Listbox Data

Introduction
This is my first attempt at writing a class and at writing a Code Project article so I hope it will be of some use. I noticed I was using a lot of listbox saving/restoring in my applications so I decided to write a class for this. The class does not contain error handling but it should work fine. To use it just add the files to your project and include ListBoxSafe.h. There are (only) two functions you can use (simplicity):

void LoadList(CListBox &list, CString FileName, int MaxItems, int ItemLen);

and

void SaveList(CListBox &ListToFill, CString FileName, int MaxItems, int MaxItemLen);

list/ListToFill is the ListBox that you need to save or fill.
FileName is the name of the file from which you want to load or to which you want to save to.
MaxItems is the maximum amount of items to be saved or loaded.
ItemLen/MaxItemLen is the maximum length of a listbox item (should be the same if you save and load).

You can give MaxItems the value 0, and it will be 999 by default.
You can give MaxItemLen/ItemLen the value 0, and it will be 30 by default.

Example
CListBoxSafe::SaveList(m_lMyList,"test.dat",0,0);
CListBoxSafe::LoadList(m_lDataList,"data.txt",0,0);

Using virtual lists

Introduction
Let's say you have a large database in your program and you want to show the database to the user. You use a CListCtrl with a couple of columns and fill it with a few thousand, maybe million elements. When you run it, you notice it's a bit (or very) slow. Wouldn't it be great if you didn't need to add all elements to the list, and let the list show them anyway? Does it sound stupid and ridiculous? That's how a virtual list works.

Virtual list
A virtual list is a list that has no data, it only knows how many data items it is supposed to have. But how does it now what data to show? The secret is that the list asks the parent for the information it needs. Assume you have a list with 100 elements, and elements 10-20 are visible. When the list is redrawing, it first asks the parent about element 10. When the parent has answered, the list redraws element 10, and then goes on to the next element.

A virtual list is sending three different messages to the parent. LVN_GETDISPINFO is sent when the list needs information. This is the most important message. The message LVN_ODFINDITEM is sent when the user tries to find an item by writing in the list. LVN_ODCACHEHINT is sent to give you a chance to cache data. You will probably don't care about this message at all.

OK, that's enough fuzzy theory, let's look on some code instead.

Creating a virtual list
Creating a virtual list isn't much harder than creating an ordinary CListCtrl. Add a list control in the resource editor as you usually do. Then check the style "Owner data", and then add a CListCtrl variable for this control. The only difference from an ordinary CListCtrl is the "Owner data" (LVS_OWNERDATA) style.

When you work with a virtual list, you use it mostly in the same way you do with a non-virtual list. Adding columns, selecting items, adding image list and much more works exactly the same way.

Add items to the list
Let's say m_list is the control variable for the list. Normally, you add data to the list like this:

m_list.InsertItem(0, _T("Hello world"));

But in a virtual list, this will not work. Instead, it is up to you to handle the data. Instead of adding, you change the number of elements the list is showing:

//"Add" 100 elements
m_list.SetItemCount(100);

If you set the item count to 100 or 1,000,000 doesn't matter, the time to run this command will still be practically zero. In a non-virtual list, adding a million elements could take hours.

Handling the LVN_GETDISPINFO message
As I said before, the list is asking the parent for information when it needs it. The list does this by sending a LVN_GETDISPINFO message. This is the most important message to handle when you are dealing with a virtual list. A typical function looks like this:

Collapsevoid CVirtualListDlg::OnGetdispinfoList(NMHDR* pNMHDR, LRESULT* pResult)
{
LV_DISPINFO* pDispInfo = (LV_DISPINFO*)pNMHDR;

//Create a pointer to the item
LV_ITEM* pItem= &(pDispInfo)->item;

//Which item number?
int itemid = pItem->iItem;

//Do the list need text information?
if (pItem->mask & LVIF_TEXT)
{
CString text;

//Which column?
if(pItem->iSubItem == 0)
{
//Text is name
text = m_database[itemid].m_name;
}
else if (pItem->iSubItem == 1)
{
//Text is slogan
text = m_database[itemid].m_slogan;
}

//Copy the text to the LV_ITEM structure
//Maximum number of characters is in pItem->cchTextMax
lstrcpyn(pItem->pszText, text, pItem->cchTextMax);
}

//Do the list need image information?
if( pItem->mask & LVIF_IMAGE)
{
//Set which image to use
pItem->iImage=m_database[itemid].m_image;

//Show check box?
if(IsCheckBoxesVisible())
{
//To enable check box, we have to enable state mask...
pItem->mask |= LVIF_STATE;
pItem->stateMask = LVIS_STATEIMAGEMASK;

if(m_database[itemid].m_checked)
{
//Turn check box on
pItem->state = INDEXTOSTATEIMAGEMASK(2);
}
else
{
//Turn check box off
pItem->state = INDEXTOSTATEIMAGEMASK(1);
}
}
}

*pResult = 0;
}

First, we create a LV_DISPINFO pointer, and then a pointer to the item. In itemid, we save which item we should handle. Then we check the mask in pItem. The mask is telling us what kind of information the list needs. First, we check if text information is needed. If it is, we first figure out which column the text is. The first column is for names, the second for slogans (several columns will be shown in report view, in other views only first column will be used).

We also check if image information is needed. If it is, we save which image to use in pItem->iImage (this is the number to an image in the image list connected to the list).

If check boxes are visible, we should send information about that when image information is requested. First, we change pItem->mask to tell that we are sending state information. We also change pItem->stateMask to tell what kind of information we are sending. Then we write if check box is on or off.

The mask could also have the flags LVIF_INDENT, LVIF_NORECOMPUTE, LVIF_PARAM, and LVIF_DI_SETITEM. But I have never used any of them, so I guess they aren't important :-).

It isn't harder to handle the LVN_GETDISPINFO message than this. Check boxes are probably the hardest, but you will probably never use any more complicated code than I have done in this example. When you have written this function, your list will almost act like a normal list. However, it might be a good idea to implement the LVN_ODFINDITEM as well.

Handling the LVN_ODFINDITEM message
First, some basic education: start Explorer and go to a folder where you have a lot of files. Press A. What happens? If you have a file or folder that begins with an 'A', that file should now be selected. Press A again. If you have more than one file that begins with an 'A', the second file should be selected. Write "AB". If there is any file that begins with 'AB', that is now selected. This is how every normal list control behaves. Aren't list controls cool? :-).

Let's look on how a list control normally searches:

Name
Anders
Anna
Annica
Bob
Emma
Emmanuel

Anna is selected. When we are writing anything, the list will search down to find the best match. If it reaches the end, it restarts at the top and searches until it is back on the start item (Anna). If "A" is written, Annika should be selected. If "AND" is written, Anders should be selected. If "ANNK" is written, the selection should stay on Anna. If "E" is written, Emma should be selected.

Unfortunately, this doesn't work with virtual lists. A virtual list doesn't try to find any item at all, unless you handle the LVN_ODFINDITEM message. I usually implement the message like this:

Collapsevoid CVirtualListDlg::OnOdfinditemList(NMHDR* pNMHDR, LRESULT* pResult)
{
// pNMHDR has information about the item we should find
// In pResult we should save which item that should be selected
NMLVFINDITEM* pFindInfo = (NMLVFINDITEM*)pNMHDR;

/* pFindInfo->iStart is from which item we should search.
We search to bottom, and then restart at top and will stop
at pFindInfo->iStart, unless we find an item that match
*/

// Set the default return value to -1
// That means we didn't find any match.
*pResult = -1;

//Is search NOT based on string?
if( (pFindInfo->lvfi.flags & LVFI_STRING) == 0 )
{
//This will probably never happend...
return;
}

//This is the string we search for
CString searchstr = pFindInfo->lvfi.psz;

int startPos = pFindInfo->iStart;
//Is startPos outside the list (happens if last item is selected)
if(startPos >= m_list.GetItemCount())
startPos = 0;

int currentPos=startPos;

//Let's search...
do
{
//Do this word begins with all characters in searchstr?
if( _tcsnicmp(m_database[currentPos].m_name,
searchstr, searchstr.GetLength()) == 0)
{
//Select this item and stop search.
*pResult = currentPos;
break;
}

//Go to next item
currentPos++;

//Need to restart at top?
if(currentPos >= m_list.GetItemCount())
currentPos = 0;

//Stop if back to start
}while(currentPos != startPos);
}

It may not be obvious how this works at a first look, but if you read it carefully, you will understand. Or, you simply skip this, and copy the code and just do the necessary changes - it's up to you :-). If the list is really large, maybe you need to make a faster version of this function, or don't implement it at all.

pFindInfo->lvfi has information on how you should search (like "Restart at top if bottom is reached" or in which direction). I have never cared about that, if you do, you should read in MSDN to get more information.

Handling the LVN_ODCACHEHINT message
LVN_ODCACHEHINT is sent to give you a chance to cache data. If you are working with a database that is in another computer in some network, maybe this is useful, but I haven't used this message in any of my programs. A function that handles this message will probably look something like this:

void CVirtualListDlg::OnOdcachehintList(NMHDR* pNMHDR, LRESULT* pResult)
{
NMLVCACHEHINT* pCacheHint = (NMLVCACHEHINT*)pNMHDR;

// ... Cache the data pCacheHint->iFrom to pCacheHint->iTo ...

*pResult = 0;
}

This is quite simple as you see. But as usual, simple things don't work :-). According to MSDN, you should override OnChildNotify and add the handler in this function. But I will not dig deeper in this, if you need more information about this, read in MSDN.

Changing an item
What should you do to change the data? This is really simple. You don't change the data in the list, but in the database instead. To redraw the list items, call CListCtrl::RedrawItems.

Check boxes
Check boxes are useful, but they are quite tricky to implement when you are working with a virtual list. In a normal non-virtual list, check boxes are toggled when you click on them or when you press space. But in a virtual list, nothing will happen. So you have to implement these events yourself. We start with a simple toggle-check-box-function:

void CVirtualListDlg::ToggleCheckBox(int item)
{
//Change check box
m_database[item].m_checked = !m_database[item].m_checked;

//And redraw
m_list.RedrawItems(item, item);
}

We will call this function when we want to change an item. The function toggles the check box value (in the database!) and forces the list to redraw the item. Quite simple. Toggling a check box when space is pressed is also quite simple. Add a message handler for the LVN_KEYDOWN message. The function should be something like this:

void CVirtualListDlg::OnKeydownList(NMHDR* pNMHDR, LRESULT* pResult)
{
LV_KEYDOWN* pLVKeyDown = (LV_KEYDOWN*)pNMHDR;

//If user press space, toggle flag on selected item
if( pLVKeyDown->wVKey == VK_SPACE )
{
//Toggle if some item is selected
if(m_list.GetSelectionMark() != -1)
ToggleCheckBox( m_list.GetSelectionMark() );
}

*pResult = 0;
}

We check if space is pressed and if any item is selected before we toggle the check box. To toggle check box when we click on it, we have to do a more complicated function. Add a message handler for the NM_CLICK message. My function looks like this:

void CVirtualListDlg::OnClickList(NMHDR* pNMHDR, LRESULT* pResult)
{
NMLISTVIEW* pNMListView = (NM_LISTVIEW*)pNMHDR;

LVHITTESTINFO hitinfo;
//Copy click point
hitinfo.pt = pNMListView->ptAction;

//Make the hit test...
int item = m_list.HitTest(&hitinfo);

if(item != -1)
{
//We hit one item... did we hit state image (check box)?
//This test only works if we are in list or report mode.
if( (hitinfo.flags & LVHT_ONITEMSTATEICON) != 0)
{
ToggleCheckBox(item);
}
}

*pResult = 0;
}

We are using CListCtrl::HitTest to see if we clicked on an item. If we did, the function returns which item we clicked on. We then use hitinfo.flags to see where we clicked. If the flag LVHT_ONITEMSTATEICON is on, then we know that the user clicked on the check box (state image).

Unfortunately, CListCtrl::HitTest doesn't work as it should if the list view is in "Icon" or "Small icon" mode. In these views, hitinfo.flags & LVHT_ONITEMSTATEICON is always 0. I haven't found a solution to this, if you do, let me now. However, using check boxes in these modes is probably quite unusual, so this is not a big problem.

Notes
Unless you are making something very unusual, you will not need to know more information than there is in this article, to use virtual lists. However, there are some minor compatibility issues between a virtual and a non-virtual list. For example, a virtual list can't sort data. But that is quite obvious, isn't it :-)? You find more information about these issues in MSDN.

When should you use a virtual list, and when should you not? For large lists, I personally prefer a virtual list. But a non-virtual list is usually easier to program (message handling is never fun), so for smaller lists, I use the ordinary list.

A very neat thing about virtual lists is that they are very easy to keep synchronized with a database. You just change the database and redraw the list if necessary. So, if you work with a list where the user should change data in the database, a virtual list could be useful even if number of items are low.

Another nice thing is that you sometimes could generate data when necessary. If you want to show row number in one column, that is very easy to do, and it takes practically no memory at all. In a non-virtual list, you would have to add this data on all items.

History

Clipboard backup (Visual C++)

Introduction
This piece of code is to help you backup your clipboard data and restore it after you have finished other clipboard operations.

My experience: while I'm developing Word add-in programs, the icon of the new-added button can only be set through clipboard by "...->PasteFace()". This will empty the clipboard data which is going to be pasted in Word. So, I wrote this class, and it helped me a lot.

Usage:

// the constructor will do backup clipboard operation
CClipboardBackup cbbackup;

// any other clipboard operations
::OpenClipboard(NULL);
::EmptyClipboard();
::SetClipboardData(......);
::CloseClipboard();
....

// restore
cbbackup.Restore();

Advertisement

Copying a Bitmap of the Client Area

The following bit of code renders the client area using OnDraw() into a bitmap. The bitmap is placed on the clipboard as a CF_BITMAP that is recognizable by most applications that accept bitmaps. This code will work will all mapping modes provided that mapping mode is set in the OnPrepareDC() function.

Collapsevoid CXStitchView::OnEditCopy()
{
CRect rect;
CClientDC dc(this);
CDC memDC;
CBitmap bitmap;

GetClientRect(&rect);

// Create memDC
memDC.CreateCompatibleDC(&dc);
bitmap.CreateCompatibleBitmap(&dc, rect.Width(), rect.Height());
CBitmap* pOldBitmap = memDC.SelectObject(&bitmap);

// Fill in memDC
memDC.FillSolidRect(rect, dc.GetBkColor());
OnPrepareDC(&memDC);
OnDraw(&memDC);

// Copy contents of memDC to clipboard
OpenClipboard();
EmptyClipboard();
SetClipboardData(CF_BITMAP, bitmap.GetSafeHandle());
CloseClipboard();

// Clean up
memDC.SelectObject(pOldBitmap);
bitmap.Detach();
}

Copying a Table of Data to the Clipboard
Placing a table of data on the clipboard is easy. It is simply a string of text. Tabs separate columns, new lines separate rows. Here's some example source.

#include

void CClipExamView::OnEditCopy()
{
// Create a shared memory file
CSharedFile sf(GMEM_MOVEABLE | GMEM_SHARE | GMEM_ZEROINIT);

// Place clipboard data in the shared memory file
RenderTableData(sf);

if (sf.GetLength() > 0) {
// Put the data on the clipboard
OpenClipboard();
EmptyClipboard();
SetClipboardData(CF_TEXT, sf.Detach());
CloseClipboard();
}
}

void CClipExamView::RenderTableData(CFile &file)
{
// Columns are separated by tabs ('\t')
// Rows are separated by new lines ('\n')
CString buffer = "1\t2\t3\n4\t5\t6\n";
file.Write(buffer, buffer.GetLength());
}

Copying Formatted Data to the Clipboard
Formatted text can support bold, italic or any other formatting that can be done in a word processor. Formatted text is usually placed on the clipboard as RTF (Rich Text Format).

The Rich Text Format is intended as an interchange format for Word-processing applications. Because of that, it is a rather large and feature rich file format. Fortunately, it is possible to describe a minimal RTF command set for creating simple formatted documents.

Basic RTF commands:
\par - Starts a new paragraph.
\tab - A tab.
\b - Enable Bold (scoped within a group)
\i - Enable Italics (scoped within a group)
\ul - Enable Underline (scoped within a group)

For example, the RTF string:

{\rtf1 {1 \tab 2 \tab 3 \par 4 \tab {\b\i 5} \tab 6}}

Source

#include

void CClipExamView::OnEditCopy()
{
// Create a shared memory file
CSharedFile sf(GMEM_MOVEABLE | GMEM_SHARE | GMEM_ZEROINIT);

// Place clipboard data in the shared memory file
RenderFormattedData(sf);

if (sf.GetLength() > 0) {
// Put the data on the clipboard
OpenClipboard();
EmptyClipboard();
SetClipboardData(::RegisterClipboardFormat(CF_RTF), sf.Detach());
CloseClipboard();
}
}

void CClipExamView::RenderFormattedData(CFile &file)
{
// RTF (Rich Text Format) - Don't forget to escape
// the \ character in your C strings!
CString buffer = "{\\rtf1 {1 \\tab 2 \\tab 3"
" \\par 4 \\tab {\\b\\i 5} \\tab 6}}";
file.Write(buffer, buffer.GetLength());
}

Getting More Info on RTF

Data Drag is coming to town... the drop target

You imagine? Right, there's more than one possibility, this time I'll give you tree. One for your private data, one for the common data in order to receive data from other applications like Excel, WinWord etc. and at last, I'll give you a handy-dandy class you can derive ANY MFC object from, to make it a drop target.

Getting the data from the dropped object, the MFC way
I assume you want to drag the contents of some rows of a CListControl of your CFormView into one of the modal dialogs mentioned earlier in this article series. In real-life, you can use this approach to implement the drop functions to any CWnd-derived object, whether in the modal dialog or not.

The first steps are the same as done when implementing the drop source:

To your drop target class, e.g. my CDialog based class CDropDialog, add a member variable of type UINT: UINT m_DragDropFormat;

In the constructor of the view, initialize it for private data exchange with: m_DragDropFormat =
::RegisterClipboardFormat("YourInterfaceClipboardFormat");

and for the common format just use:

m_DragDorpFormat = CF_TEXT;

Add the following lines to stdafx.h: #include
#include

In your application's InitInstance function, make a call to AfxOleInit() before creating the document template
If the window used as drop target is CView-derived, you are now in luck, most of it is at the hand. In the OnInitialUpdate function, call the Register() function and overwriting the functions OnDragOver and OnDrop (implementation same as CInterfaceDropTarget in step 9) should be enough in "normal" cases - READY!
If you have another kind of target, there's some more work.
Use the ClassWizard to create a new generic(!) class derived from the MFC(!) class COleDropTarget. I call it CInterfaceDropTarget.
Create and initialize a UINT m_DragDropFormat as in step 2.
Create - at least - the functions OnDragOver and OnDrop. CollapseDROPEFFECT CInterfaceDropTarget::OnDragOver (CWnd *pDrop,
COleDataObject* pDataObject, DWORD dwKeyState, CPoint point )
{
CFile *pFile = pDataObject->GetFileData(m_DragDropFormat);
if (pFile != NULL)
// perhaps some point checking here?
return DROPEFFECT_COPY; // data fits
else
return DROPEFFECT_NONE; // data won't fit
}

BOOL CInterfaceDropTarget::OnDrop(CWnd *pDrop,
COleDataObject* pDataObject, DROPEFFECT dropEffect, CPoint point )
{
CFile *pFile = pDataObject->GetFileData(m_DragDropFormat);
if (pFile != NULL)
{
int number, colCou;
CString Data;
// perhaps some point checking first?
TRY
{
CArchive ar(&file, CArchive::load);
TRY
{
if (DragDropFormat != CF_TEXT)
{
// "Serialize" your data object from the archive
// (yes, you may use YourObject.Serialize(ar) here!)
ar >> number;
ar >> colCou;

for (int i=0; i {
ar >> Data ;
#pragma message(__FILE__ " dont't forget to process Data here.....")
}
}
else
{
CString Data, t;

TRY
{
while(ar.ReadString(t))
Data += t + "\n";
}
#pragma message(__FILE__ " ... and here!")
CATCH_ALL(eInnerMost)
{
#ifdef _DEBUG
TCHAR szCause[255];
CString strFormatted;
eInnerMost->GetErrorMessage(szCause, 255);
strFormatted = _T("Exception: ");
strFormatted += szCause;
AfxMessageBox(strFormatted);
#endif //_DEBUG
ASSERT(FALSE);
}
END_CATCH_ALL;
}
ar.Close();
}
CATCH_ALL(eInner)
{
// exception while reading
// from or closing the archive
ASSERT(FALSE);
}
END_CATCH_ALL;
}
CATCH_ALL(eOuter)
{
// exception in the destructor of ar
ASSERT(FALSE);
}
END_CATCH_ALL;
return TRUE;
}
return COleDropTarget::OnDrop(pDrop,
pDataObject, dropEffect, point);
}

Don't forget to process the data in the OnDrop function. You should send the just-dropped-object to your CWnd-class and "do something" with it there. The example does this with the functions ProcessData(CString data) and ProcessData(int rowcount, int linecount, CString Data).
In the CWnd-derived class used as drop target, add a member variable of type CInterfaceDropTarget, for example's sake name it m_DT.
At any point where this window exists (for example: OnInitDialog is great) call the Register function of m_DT: BOOL CDropDialog::OnInitDialog()
{
CDialog::OnInitDialog();
m_DT.Register(this);
// the other stuff follows ....

Time Management for System Administrators

Time Management for System Administrators contains useful advice for SysAdmins looking to use their time more effectively. If you are a techie who wonders why you get bogged down with little tasks while not getting your projects done, this is the book for you. If you don't have the time to read this book, you definitely need to read it.



--------------------------------------------------------------------------------
Copyright notice: All reader-contributed material on freshmeat.net is the property and responsibility of its author; for reprint rights, please contact the author directly.
--------------------------------------------------------------------------------


Title: Time Management for System Administrators
Author: Thomas A. Limoncelli
Publisher: O'Reilly
Purchase URL: http://www.oreilly.com/catalog/timemgmt/


This is a compact book, weighing in at around 200 pages. The size is appropriate for a book intended to help people with too little time. It is basically a pile of advice for those of us who are constantly fixing broken systems, answering user requests, attending meetings, and maybe sometimes actually working on our projects. Some of this advice you have probably figured out on your own, some you will find useful, and some you will disagree with. That's OK; take what you need and leave the rest.

The first chapter is in some ways the most valuable part of the book. It covers how to deal with interruptions, and lists some general principles of time management.

The book moves on to discuss various ways to maintain focus while working on tasks and projects, so that you actually get things done instead of responding to interruptions and destroying your concentration through multitasking. Then it recommends routines, so that you don't forget to do things and so that you don't need to worry about what to do. I have found the advice in these chapters to be useful.

The core of the book is "The Cycle" -- a system for managing your to-do items, appointments, calendar, and even long-term goals. I've been trying out parts of it, and have found that it has helped me avoid schedule conflicts, made me less likely to drop to-do items, and improved my follow-up. So far, it hasn't actually helped me get down to 40 work hours a week, although in all fairness, I'm not yet doing the full system.

The rest of the book discusses prioritization, email management (in particular, the principle of "touch once" -- which I have found to be an extremely effective way of dealing with email), time wasters, documentation (which is time management -- documentation helps you do things faster or delegate them to other people), and automation. Most of the advice here has been useful as well. My only complaint is that the discussion on shell scripting did not seem very useful -- if I didn't already know shell scripting, it would not have taught me much, or convinced me that I needed this skill for time management.

The book also contains advice on various topics that are somewhat tangential. Such topics include customer management, long-term goals, "managing your boss", stress management (which gets its own chapter), and personal time. While not directly related to the nominal purpose of the book, the points mostly seemed valid and useful.

On the whole, I'd say that this book is well worth its $25 asking price. I've known for a while that I have time management problems, so I once bought a different time management book, but never finished it; the other book seemed more oriented towards executives and managers. This book speaks to system administrators, and it does a good job. It's not a panacea -- to fix your time management problems, you not only need to know what the problems are, you also need to go to considerable effort to change your habits. But this book's advice has already helped me to improve my time management, and hopefully it will help you, too.