TimeSort Error

Michael Sage

December 05, 2013 00:10

Hi 

I'm seeing a bug with Custom sort when doing a sort on DateTime. I have listed my custom sort code as well as the exception below. I believe this happens when updating a datetime of a record already in the list , a result of which causes the record to go to the top of the list. For example, if we have 10 records with timestamps from 9:00 to 9:10 each in a one minute increment and we update the 5th record from 9:05 to 9:30 , it might cause a problem.  I could be wrong, but this is my observation so far. 

Please let me know what you find.

Thanks.

internal class FillTimeCustomSort : ICustomSort
{
public int Compare(Row row1, Row row2, string fieldId, object value1, object value2, int defaultResult)
{
try
{
if (fieldId == "Time")
{
FillsModel tModel1 = row1.DataObject as FillsModel;
FillsModel tModel2 = row2.DataObject as FillsModel;

if (tModel1 != null && tModel2 != null)
{
DateTime t1 = ((FillsModel)row1.DataObject).TimeStamp;
DateTime t2 = ((FillsModel)row2.DataObject).TimeStamp;

if (t1 != null && t2 != null)
{
if (t1.Equals(t2))
return 0;
else
return t1.CompareTo(t2);
}
}
}
}
catch (Exception err)
{
Console.WriteLine("Error in TimeCustomSort " + err.ToString());
}

return defaultResult;
}
}

 

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************** Exception Text **************
System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index
at System.Collections.ArrayList.get_Item(Int32 index)
at Dapfor.Net.Internal.Helper.SingleNodeSort(ArrayList list, Int32 index, IComparer comparer)
at Dapfor.Net.Internal.NodeContainer.MoveNodeToUpdatedPosition(IList`1 sort, ICustomSort customSort, Node node, Int32 oldPosition)
at Dapfor.Net.Internal.Node.SafeUpdate()
at Dapfor.Net.Internal.Node.PropertyIdChangedTask.Execute(Node node, IDataField field, Boolean highlightRow)
at Dapfor.Net.Internal.Node.PropertyIdChangedTask.Execute()
at Dapfor.Net.Threading.GuiDispatcher.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

0

• 

  Dapfor Team

  December 05, 2013 09:03

  Hi,

  The problem is in incorrect implementation of the Compare() method. Indeed, if the grid has sorted columns it stores rows in a sorted way. When you change the sort in a column or the grid gets a notification from INotifyPropertyChanged it calls a kind of the List.Sort (IComparer) method. Thus during value comparing they ​​should be unchanged. When you compare TimeStamp values they can be changed and the grid will throw exceptions.

  In order to avoid this problem, the grid does a snapshot of values ​​by which it sorts. These values are passed as value1 and value2 to the Compare() method. So you should cast these values and compare them.

  Best regards,

  Dapfor

   

  0
• 

  Michael Sage

  December 05, 2013 15:23

  Thanks, that worked. I appreciate your quick response. I know I can be pain in asking too many questions at times but thanks for bearing with me.

  0
• 

  Dapfor Team

  December 05, 2013 15:38

  Hi,

  We are interested in quality of our products and answering your questions, we better understand our customers' needs.

  Best regards,

  Dapfor

  0

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