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System.ArgumentNullException: Value cannot be null

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GridView

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WILLIAM asked on 06 Sep 2013, 04:35 PM

Hi telerik team,

I've come across a really weird situation and I have not been able to successfully debug it. I was wondering if you could give me some clues to look for or events to subscribe to try and figure it out.

About the grid:
It has several columns of various types.
All columns are read-only except for one which is a date column
The grid is grouped by the date column
This grid one of several controls in a xaml view.

Our user has found an issue where if she updates the date (I believe either by manually editing the date, or using the date picker). She immediately clicks on a completely different view (not the view that the grid is part of) and I get the exception below. It seems that all updating of the field and the underlying datasource all works just find. Also, this only happens the first time you edit a date. You can continue to change dates as you wish an with no exceptions; it only happens from the first date change.

I have subscribed to the Cell.LostFocus and GridView.LostFocus events and these are not fired when I get the exception.

Any ideas on how to approach this would be greatly appreciated!!
Thanks

System.ArgumentNullException: Value cannot be null.

Parameter name: element

at Telerik.Windows.Controls.ParentOfTypeExtensions.<GetParents>d__0.MoveNext()

at System.Linq.Enumerable.<OfTypeIterator>d__aa`1.MoveNext()

at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection)

at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source)

at Telerik.Windows.Controls.GridView.GridViewCell.HandlePendingEdit(UIElement focusedElement)

at Telerik.Windows.Controls.GridView.GridViewCell.HandlePendingEditOnLostFocus()

at Telerik.Windows.Controls.GridView.GridViewCell.Editor_LostFocus(Object sender, RoutedEventArgs e)

at MS.Internal.CoreInvokeHandler.InvokeEventHandler(UInt32 typeIndex, Delegate handlerDelegate, Object sender, Object args)

at MS.Internal.JoltHelper.FireEvent(IntPtr unmanagedObj, IntPtr unmanagedObjArgs, Int32 argsTypeIndex, Int32 actualArgsTypeIndex, String eventName, UInt32 flags)

System.ArgumentNullException: Value cannot be null

2 Answers, 1 is accepted