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Error when opening date picker inside grid

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GridView
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JP
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JP asked on 22 Apr 2009, 03:04 PM
Hello,

We have come across an error when trying to use a date picker in a grid (v2009.1.413.35).  When you try to open a date picker that is being used in a grid an 'Object reference not set to an instance of an object' exception is thrown.  This problem seems to only occur on machines running Vista 64. 

Steps to reproduce:
1. Install the Telerik controls on a machine running Vista 64
2. Launch the Example app
3. Go to the GridView Editors example
4. Try to edit a date column

Here's the stack trace:
2009-03-25 14:22:40,609 [1] ERROR IRC.Gear.WorkItemManager.Wpf.App - Unhandled exception. System.NullReferenceException: Object reference not set to an instance of an object. at System.Windows.Automation.Peers.AutomationPeer.EnsureChildren() at System.Windows.Automation.Peers.AutomationPeer.UpdateChildren() at System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree() at System.Windows.Automation.Peers.AutomationPeer.UpdatePeer(Object arg) at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Boolean isSingleParameter) at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler)

Please let me know when there is a fix available.

Thanks,

Joel



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Milan
Telerik team
answered on 27 Apr 2009, 02:33 PM
Hi Joel,

I have tried to reproduced the exception by following your notes but I wan unable to crash the demo. Does this also happen if you create a stand-alone application with data editing?

Sincerely yours,
Milan
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JP
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answered on 07 May 2009, 06:40 PM
Hi Milan,

We also tried creating a very simple application with data editing and the same problem occurred.  On the problem machines the error was happening in our app, in the Telerik sample app, and in the simple data editing app.  So far this problem has only occurred on two machines and both of them had these specs:

Compaq 8710w laptop
Vista Business 64-bit
6GB RAM
Visual Studio 2008 SP1
Telerik RadControls For WPF Q1 2009 installed

One of the users recently upgraded to Windows 7 (RC 64-bit) and now he doesn't experience this problem anymore.

Hopefully some of this information is useful.

Joel


0
Milan
Telerik team
answered on 09 May 2009, 08:07 AM
Hi Joel,

Still trying to reproduce the exception but I have found similar problems on google that suggest that the "Tablet PC Input Service" is involved in such scenarios. It might be a shot in the dark but you could disable the service and see if the exception is still there.
It seems that such exceptions are very rare and very difficult to reproduce but we keep trying to find the exact cause.

Greetings,
Milan
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JP
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answered on 11 May 2009, 03:58 PM
Hi Milan,

We tried disabling that service and it had no effect.  The problem still occurred.  If you have anything else you'd like us to try, just let us know.

Thanks for your help, it is much appreciated.

Joel
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Milan
Telerik team
answered on 15 May 2009, 01:08 PM
Hello Joel,

We got an idea that might allow us to get some information about the original source of the problem. Before running your application turn on the "Break on exception" feature for all exception groups from Debug -> Exceptions. Now when the exception occurs some more information might be available in the exception dialog. May I ask you to record all data like stack trace, inner sceptions, etc and send it to us?

Sincerely yours,
Milan
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JP
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answered on 15 May 2009, 08:45 PM
Hi Milan,

It hasn't happened on our any of our developer's machines because none of us seem to have Vista 64 on our dev boxes.  I'll get one of the users that was experiencing this problem to install VS2008 and try your suggestion.  It will take a bit of time though.  I'll let you know what I find out.

Thanks,

Joel
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Michael Kolesnikov
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answered on 18 Jan 2010, 03:12 PM

Hello,

 

 We have the similar problem. We (developers) could not repeat Exception, but one of the clients gets it sometimes.

 It would be great, If you provide any information how can we avoid this exception and in what situations it can occur. Thank you!

 Description:

   What: 

Object reference not set to an instance of an object.
System.NullReferenceException: Object reference not set to an instance of an object.
at System.Windows.Automation.Peers.AutomationPeer.EnsureChildren()
at System.Windows.Automation.Peers.AutomationPeer.UpdateChildren()
at System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree()
at System.Windows.Automation.Peers.AutomationPeer.UpdatePeer(Object arg)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Boolean isSingleParameter)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler)

==================================

   How occurs:

Move focus to some other application and return to current application.

==================================

  How often:

Sometimes - not always.

==================================

 PC, where occurs:

 Windows Vista SP2 Bussines, Telerik 2009.2.813.35.

0
Milan
Telerik team
answered on 20 Jan 2010, 01:25 PM
Hi Michael Kolesnikov,

Unfortunately we haven't been able to reproduce this exception in our environment and it is a bit difficult to provide a solution. 

Thank you providing a stack trace information. Unfortunately the stack trace only reveals that the exception occurs somewhere in the WPF framework and there is no information about our classes. Is this the whole piece of information. If we can get more detailed stack trace we might be able to determine the code that fails. 

Sincerely yours,
Milan
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Michael Kolesnikov
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answered on 26 Jan 2010, 12:54 PM

Hello Milan,

 Thank you for your time! We've got this exception with the usage of Log4Net and the code snippet below.

        /// <summary>  
        /// Global Error Handler for the WPF application  
        /// Logs the error in the eventlog and displays a Messagebox with the error message  
        /// </summary>  
        /// <param name="sender"></param>  
        /// <param name="e"></param>  
        private void Application_DispatcherUnhandledException(object sender, System.Windows.Threading.DispatcherUnhandledExceptionEventArgs e)  
        {  
            log.Fatal(e.Exception.Message, e.Exception);  
 
            Exception exceptionToShow = e.Exception;  
 
            if (e.Exception.InnerException != null)  
            {  
                exceptionToShow = e.Exception.InnerException;  
                log.Fatal(e.Exception.InnerException.Message, e.Exception.InnerException);  
            }  
              
 
            e.Handled = true;  
        } 

So, I guess that there were no any inner exceptions, and we have provided you all that we have in log file. As I have mentioned, we can not get this exception on our developer's PCs.  Please teach me, if you know, which else helpful information can we retrieve from Exception and how? Thanks.

Best regards

Michael

0
Milan
Telerik team
answered on 28 Jan 2010, 08:36 AM
Hi Michael Kolesnikov,

May I ask you to open a support ticket and send us the application that fails so that we can try to reproduce the exception on our machines.  I guess that this is the only way that we could possibly resolve the problem. 

Thank you for your patience and cooperation.


Kind regards,
Milan
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Steffen
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Veteran
answered on 09 Jun 2010, 11:32 AM
Hi,

Same problem occurs randomly but always on the same UserControl (with multiple GridViews).
any update on this?

Best Regards
Steffen
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Vlad
Telerik team
answered on 10 Jun 2010, 09:37 AM
Hi Steffen,

 Can you post more info about your grid version?

Sincerely yours,
Vlad
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Steffen
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answered on 10 Jun 2010, 09:56 AM
Hi,

I'm using Telerik.Windows.Controls.GridView 2010.1.422.35.
I think it happens when the UserControl gets or looses focus (but only sometimes).
It's a "normal" Desktop-Application - no special Input-devices used.
 
This exception is thrown twice:

System.NullReferenceException: Der Objektverweis wurde nicht auf eine Objektinstanz festgelegt.
   bei System.Windows.Automation.Peers.AutomationPeer.EnsureChildren()
   bei System.Windows.Automation.Peers.AutomationPeer.UpdateChildren()
   bei System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree()
   bei System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree()
   bei System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree()
   bei System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree()
   bei System.Windows.Automation.Peers.AutomationPeer.UpdateSubtree()
   bei System.Windows.Automation.Peers.AutomationPeer.UpdatePeer(Object arg)
   bei System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Boolean isSingleParameter)
   bei System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Boolean isSingleParameter, Delegate catchHandler):

Best Regards
Steffen



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Yavor Georgiev
Telerik team
answered on 10 Jun 2010, 10:06 AM
Hi Steffen,

 Please let us know a bit more about your environment. Do the machines that exhibit this behavior possess any touch functionality, such as TabletPC Input Services, touchscreen, digitizer, etc.?

Greetings,
Yavor Georgiev
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Steffen
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answered on 10 Jun 2010, 10:18 AM
Hi,

it happens on my dev-machine (with 2 "normal" TFT's).
Just USB-mouse and USB-keyboard - that's it.
When i catch the exception the application seems to continue running without problems.



Best Regards
Steffen
0
Yavor Georgiev
Telerik team
answered on 10 Jun 2010, 02:30 PM
Hello Steffen,

 Could you please open a support ticket and attach a sample project that reproduces this problem? Also, please let us know what version of Windows you use (Vista 32, Vista 64, 7 32, etc.).

Greetings,
Yavor Georgiev
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Steffen
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answered on 10 Jun 2010, 02:43 PM
Hi,

I'm using Windows 7 64 bit.
Sampleproject is difficult because the Usercontrol is dependend on much application-specific stuff and won't run on its own without a lot of work.


Best Regards
Steffen
0
Yavor Georgiev
Telerik team
answered on 10 Jun 2010, 02:48 PM
Hello Steffen,

 Could you please try and make a new project so that it throws this exception? Automation exceptions are really tricky to investigate, so we need as much assistance on your part as possible.

Greetings,
Yavor Georgiev
the Telerik team

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Steffen
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answered on 10 Jun 2010, 03:21 PM
Hi,

I'm sorry but I don't even know how to reproduce the exception in my working project right now. It only happened 2 or 3 times from hundreds of times this UserControl was used. And also the UserControl has changed much in the meantime. One thing that pretty much stayed the same is the main-gridview. I'll post the XAML. Maybe this helps a little. As soon as I'm able to reliably reproduce the exception I will try to give you a sample. It's not a critical bug to my application - its just weird.
                        <telerik:RadGridView Grid.Row="2" Name="radgv_loadSpreading" ItemsSource="{x:Null}" ShowGroupPanel="False" AutoGenerateColumns="False" VerticalAlignment="Stretch" HorizontalAlignment="Stretch" ignore:ColumnsWidthMode="Auto" CanUserInsertRows="False" CanUserReorderColumns="False" CanUserResizeColumns="False" CanUserSortColumns="False" IsFilteringAllowed="False"  EditTriggers="None" RowIndicatorVisibility="Collapsed" > 
                            <telerik:RadGridView.Columns> 
                                <telerik:GridViewDataColumn IsReadOnly="False"
                                    <telerik:GridViewColumn.CellTemplate> 
                                        <DataTemplate> 
                                            <Expander ExpandDirection="Down" IsExpanded="{Binding Path=aufgeklappt}" > 
                                                <Expander.Header> 
                                                    <StackPanel Orientation="Vertical"
                                                        <StackPanel Orientation="Horizontal" Margin="5"
                                                            <my:NumericTextBox Width="50" Text="{Binding Path=volumen, NotifyOnSourceUpdated=True}" SourceUpdated="revalidate"/> 
                                                            <Label Content="m³" Margin="5,0,0,0" /> 
                                                            <Label Content="{x:Static properties:Resources.Von}" Margin="5,0,5,0"/> 
                                                            <Label Content="{Binding Path=anzeigeBL, FallbackValue='?'}"/> 
                                                            <Label Content="{x:Static properties:Resources.Nach}" Margin="5,0,5,0"/> 
                                                            <Label Content="{Binding Path=anzeigeEL, FallbackValue='?'}"/> 
                                                            <Label Content="{x:Static properties:Resources.ZwischenDem}" Margin="5,0,5,0"/> 
                                                            <telerik:RadDatePicker Name="dp_dateFrom" SelectedDate="{Binding Path=terminVon, Mode=TwoWay, NotifyOnSourceUpdated = True}" SourceUpdated="revalidate" Width="90"/> 
                                                            <Label Content="{x:Static properties:Resources.und}" Margin="5,0,5,0"/> 
                                                            <telerik:RadDatePicker Name="dp_dateTo" SelectedDate="{Binding Path=terminBis, Mode=TwoWay, NotifyOnSourceUpdated = True}" SourceUpdated="revalidate" Width="90"/> 
 
                                                        </StackPanel> 
 
                                                        <StackPanel Orientation="Horizontal" Margin="5"
                                                            <Label Content="{x:Static properties:Resources.Entfernung}"  /> 
                                                            <my:NumericTextBox Width="50" Text="{Binding Path=entfernung, StringFormat=F2}" Margin="5,0,5,0" /> 
                                                            <Label Content="km"/> 
 
                                                            <Label Content="{x:Static properties:Resources.Preis}" Margin="10,0,0,0"/> 
                                                            <my:NumericTextBox Width="100" Text="{Binding Path=preis, StringFormat=C}" Margin="5,0,0,0" /> 
 
                                                            <CheckBox VerticalContentAlignment="Center" VerticalAlignment="Center" Content="{x:Static properties:Resources.UnabhaengigFahrbar}" Margin="5,0,0,0" IsChecked="{Binding Path=unabhaengigFahrbar}"/> 
 
                                                            <CheckBox VerticalContentAlignment="Center" VerticalAlignment="Center" Name="cb_publish" Content="{x:Static properties:Resources.FahrtAbgeben}" Margin="5,0,0,0"/> 
                                                            <Button Name="btn_deleteSpreading" Click="btn_deleteSpreading_Click" Margin="50,0,0,0" ToolTip="{x:Static properties:Resources.FahrtLoeschen}" Height="21" Padding="0"
                                                                <Image Height="21" Width="21"  Source="/MoviNeo;component/MainModule/images/loeschen.gif" Margin="0"/> 
                                                            </Button> 
 
                                                        </StackPanel> 
 
                                                    </StackPanel> 
                                                </Expander.Header> 
                                                <Grid> 
                                                    <Grid.ColumnDefinitions> 
                                                        <ColumnDefinition/> 
                                                        <ColumnDefinition/> 
                                                        <ColumnDefinition/> 
                                                    </Grid.ColumnDefinitions> 
                                                    <telerik:RadGridView Grid.Column="0" HorizontalAlignment="Center" Width="202" ItemsSource="{Binding Path=FK_tbl_fahrt_tbl_fahrt_has_tbl_leistung}" ShowGroupPanel="False" AutoGenerateColumns="False" IsFilteringAllowed="False" CanUserFreezeColumns="False" CanUserInsertRows="False" CanUserReorderColumns="False" CanUserSortColumns="False" CanUserResizeColumns="False"   EditTriggers="None" RowIndicatorVisibility="Collapsed"
                                                        <telerik:RadGridView.Columns> 
 
                                                            <telerik:GridViewDataColumn Header="{x:Static properties:Resources.Leistung}" IsReadOnly="False" Width="100"
                                                                <telerik:GridViewColumn.CellTemplate> 
                                                                    <DataTemplate> 
                                                                        <TextBlock Text="{Binding Path=kuerzel}"/> 
                                                                    </DataTemplate> 
                                                                </telerik:GridViewColumn.CellTemplate> 
                                                            </telerik:GridViewDataColumn> 
 
                                                            <telerik:GridViewDataColumn Header="{x:Static properties:Resources.BL}" IsReadOnly="False" Width="50"
                                                                <telerik:GridViewColumn.CellTemplate> 
                                                                    <DataTemplate> 
                                                                        <my:NumericTextBox Text="{Binding Path=stundenBL}"/> 
                                                                    </DataTemplate> 
                                                                </telerik:GridViewColumn.CellTemplate> 
                                                            </telerik:GridViewDataColumn> 
 
                                                            <telerik:GridViewDataColumn Header="{x:Static properties:Resources.EL}" IsReadOnly="False" Width="50"
                                                                <telerik:GridViewColumn.CellTemplate> 
                                                                    <DataTemplate> 
                                                                        <my:NumericTextBox Text="{Binding Path=stundenEL}"/> 
                                                                    </DataTemplate> 
                                                                </telerik:GridViewColumn.CellTemplate> 
                                                            </telerik:GridViewDataColumn> 
 
                                                        </telerik:RadGridView.Columns> 
                                                    </telerik:RadGridView> 
 
                                                    <telerik:RadGridView Grid.Column="1" HorizontalAlignment="Center" Width="202" ItemsSource="{Binding Path=FK_tbl_fahrt_tbl_fahrt_has_tbl_material}" ShowGroupPanel="False" AutoGenerateColumns="False" IsFilteringAllowed="False" CanUserFreezeColumns="False" CanUserInsertRows="False" CanUserReorderColumns="False" CanUserSortColumns="False" CanUserResizeColumns="False"  EditTriggers="None" RowIndicatorVisibility="Collapsed"
                                                        <telerik:RadGridView.Columns> 
 
                                                            <telerik:GridViewDataColumn Header="{x:Static properties:Resources.Material}" IsReadOnly="False" Width="100"
                                                                <telerik:GridViewColumn.CellTemplate> 
                                                                    <DataTemplate> 
                                                                        <TextBlock Text="{Binding Path=kuerzel}"/> 
                                                                    </DataTemplate> 
                                                                </telerik:GridViewColumn.CellTemplate> 
                                                            </telerik:GridViewDataColumn> 
 
                                                            <telerik:GridViewDataColumn Header="{x:Static properties:Resources.BL}" IsReadOnly="False" Width="50"
                                                                <telerik:GridViewColumn.CellTemplate> 
                                                                    <DataTemplate> 
                                                                        <my:NumericTextBox Text="{Binding Path=anzahlBL}"/> 
                                                                    </DataTemplate> 
                                                                </telerik:GridViewColumn.CellTemplate> 
                                                            </telerik:GridViewDataColumn> 
 
                                                            <telerik:GridViewDataColumn Header="{x:Static properties:Resources.EL}" IsReadOnly="False" Width="50"
                                                                <telerik:GridViewColumn.CellTemplate> 
                                                                    <DataTemplate> 
                                                                        <my:NumericTextBox Text="{Binding Path=anzahlEL}"/> 
                                                                    </DataTemplate> 
                                                                </telerik:GridViewColumn.CellTemplate> 
                                                            </telerik:GridViewDataColumn> 
 
                                                        </telerik:RadGridView.Columns> 
                                                    </telerik:RadGridView> 
 
                                                    <telerik:RadGridView Grid.Column="2" HorizontalAlignment="Center" Width="202" ItemsSource="{Binding Path=FK_tbl_fahrt_tbl_fahrt_has_tbl_transportleistung}" ShowGroupPanel="False" AutoGenerateColumns="False" IsFilteringAllowed="False" CanUserFreezeColumns="False" CanUserInsertRows="False" CanUserReorderColumns="False" CanUserSortColumns="False" CanUserResizeColumns="False"  EditTriggers="None" RowIndicatorVisibility="Collapsed"
                                                        <telerik:RadGridView.Columns> 
 
                                                            <telerik:GridViewDataColumn Header="{x:Static properties:Resources.Typ}" IsReadOnly="False" Width="100"
                                                                <telerik:GridViewColumn.CellTemplate> 
                                                                    <DataTemplate> 
                                                                        <TextBlock Text="{Binding Path=leistungsTyp, Converter={StaticResource transportServiceTypeToStringConverter}}"/> 
                                                                    </DataTemplate> 
                                                                </telerik:GridViewColumn.CellTemplate> 
                                                            </telerik:GridViewDataColumn> 
 
                                                            <telerik:GridViewDataColumn Header="{x:Static properties:Resources.Transport}" IsReadOnly="False" Width="30"
                                                                <telerik:GridViewColumn.CellTemplate> 
                                                                    <DataTemplate> 
                                                                        <TextBlock Text="{Binding Path=kuerzel}"/> 
                                                                    </DataTemplate> 
                                                                </telerik:GridViewColumn.CellTemplate> 
                                                            </telerik:GridViewDataColumn> 
 
                                                            <telerik:GridViewDataColumn Header="{x:Static properties:Resources.Anzahl}" IsReadOnly="False" Width="36"
                                                                <telerik:GridViewColumn.CellTemplate> 
                                                                    <DataTemplate> 
                                                                        <my:NumericTextBox Text="{Binding Path=anzahl}"/> 
                                                                    </DataTemplate> 
                                                                </telerik:GridViewColumn.CellTemplate> 
                                                            </telerik:GridViewDataColumn> 
 
                                                            <telerik:GridViewDataColumn Header="{x:Static properties:Resources.Stunden}" IsReadOnly="False" Width="36"
                                                                <telerik:GridViewColumn.CellTemplate> 
                                                                    <DataTemplate> 
                                                                        <my:NumericTextBox Text="{Binding Path=stunden, StringFormat=F2}"/> 
                                                                    </DataTemplate> 
                                                                </telerik:GridViewColumn.CellTemplate> 
                                                            </telerik:GridViewDataColumn> 
 
                                                        </telerik:RadGridView.Columns> 
                                                    </telerik:RadGridView> 
                                                </Grid> 
                                            </Expander> 
                                        </DataTemplate> 
                                    </telerik:GridViewColumn.CellTemplate> 
                                </telerik:GridViewDataColumn> 
                            </telerik:RadGridView.Columns> 
                        </telerik:RadGridView> 

Best Regards
Steffen
0
Yavor Georgiev
Telerik team
answered on 10 Jun 2010, 04:32 PM
Hi Steffen,

 Thank you for your assistance. We'll continue trying to debug this. In the mean time, please let us know if you encounter such an exception again and under what circumstances.

Kind regards,
Yavor Georgiev
the Telerik team

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Usame Esendir
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answered on 03 Nov 2010, 02:14 PM
Hi All,

I had the same problem but now it has been solved :)
The problem has nothing to do with telerik, it is .net framework.

Install  NDP40-KB2297328 and NDP40-KB2413613 (in order) then restart your computer.

Everything is fine now.

Hope this helps to you.
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Usame Esendir
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answered on 12 Nov 2010, 10:23 AM
In my last post I have declared that the solution has been solved but it is not actually solved.
I am using HP TouchSmart tx2 notebook and after installing those updates while restarting I have connected a monitor to my notebook.
When there is a external monitor program runs normally but when I remove the monitor and restart the computer then I get same error.

Anyhow I was having this error in some of my grids and those have a common which is the line below.

<telerik:GridViewComboBoxColumn x:Name="cmbState" Header="{lex:LocText Key=State, Dict=GridColumns, Assembly=CMCore}" SelectedValueMemberPath="Index" DataMemberBinding="{Binding Path=JobState}" DisplayMemberPath="Value" />

When I remove GridViewComboBoxColum line above, exception is not thrown on load.

I don't know who has to solve but someone should, either telerik or microsoft.
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Vlad
Telerik team
answered on 15 Nov 2010, 11:17 AM
Hi,

 Can you post more info about your grid version? 

Best wishes,
Vlad
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Rayne
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answered on 07 Sep 2011, 01:53 PM
I know this is an old thread, but I was wondering if this was ever resolved. I'm getting those random NullReferenceException errors in automation and the component that seems to causing trouble is a RadGridView with a GridViewComboBox Column.

I'm trying to track down what could be causing this issue so I wanted to see if anything was resolved.
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Rossen Hristov
Telerik team
answered on 07 Sep 2011, 02:27 PM
Hi Rayne,

We don't know whether we have resolved this exact issue, since Usame never wrote us back. We have made many fixes in the last year. Furthermore, Silverlight as a platform got several updates. So it is quite possible that this issue has gone away, but we can't be 100% sure unless we have a sample project which reproduces it.

Are you getting these exceptions with our last official version, which is 2011 Q2? In case you are, could you prepare a small dummy project that exhibits these exception.

The thing is, we have to be able to reproduce and debug an exception in order to be able track it down and fix it, which I am sure you understand as a fellow developer.

All the best,
Ross
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Milan
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