Selection Item Changed Null Reference Exception

10 posts, 0 answers
  1. Damon
    Damon avatar
    4 posts
    Member since:
    Aug 2010

    Posted 15 Aug 2010 Link to this post

    We recently upgraded our solution to the Q2 2010 Sp1 version and now whenever the SelectedItem or SelectedIndex of our combo boxes is changed we recieve a null reference exception with the following call stack:

       at Telerik.Windows.Controls.RadComboBoxAutomationPeer.RaiseSelectionEvents(SelectionChangedEventArgs e)
       at Telerik.Windows.Controls.RadComboBox.OnSelectionChanged(SelectionChangedEventArgs e)
       at System.Windows.Controls.Primitives.Selector.InvokeSelectionChanged(List`1 unselectedItems, List`1 selectedItems)
       at System.Windows.Controls.Primitives.Selector.SelectionChanger.End()
       at System.Windows.Controls.Primitives.Selector.SelectionChanger.SelectJustThisItem(Object item, Boolean assumeInItemsCollection)
       at System.Windows.Controls.Primitives.Selector.OnSelectedItemChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
       at System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
       at System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
       at System.Windows.DependencyObject.NotifyPropertyChange(DependencyPropertyChangedEventArgs args)
       at System.Windows.DependencyObject.UpdateEffectiveValue(EntryIndex entryIndex, DependencyProperty dp, PropertyMetadata metadata, EffectiveValueEntry oldEntry, EffectiveValueEntry& newEntry, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType)
       at System.Windows.DependencyObject.InvalidateProperty(DependencyProperty dp)
       at System.Windows.Data.BindingExpressionBase.Invalidate(Boolean isASubPropertyChange)
       at System.Windows.Data.BindingExpression.TransferValue(Object newValue, Boolean isASubPropertyChange)
       at System.Windows.Data.BindingExpression.Activate(Object item)
       at System.Windows.Data.BindingExpression.AttachToContext(AttachAttempt attempt)
       at System.Windows.Data.BindingExpression.MS.Internal.Data.IDataBindEngineClient.AttachToContext(Boolean lastChance)
       at MS.Internal.Data.DataBindEngine.Task.Run(Boolean lastChance)
       at MS.Internal.Data.DataBindEngine.Run(Object arg)
       at MS.Internal.Data.DataBindEngine.OnLayoutUpdated(Object sender, EventArgs e)
       at System.Windows.ContextLayoutManager.fireLayoutUpdateEvent()
       at System.Windows.ContextLayoutManager.UpdateLayout()
       at System.Windows.UIElement.UpdateLayout()
       at System.Windows.Interop.HwndSource.SetLayoutSize()
       at System.Windows.Interop.HwndSource.set_RootVisualInternal(Visual value)
       at System.Windows.Interop.HwndSource.set_RootVisual(Visual value)
       at System.Windows.Window.SetRootVisual()
       at System.Windows.Window.SetRootVisualAndUpdateSTC()
       at System.Windows.Window.SetupInitialState(Double requestedTop, Double requestedLeft, Double requestedWidth, Double requestedHeight)
       at System.Windows.Window.CreateSourceWindow(Boolean duringShow)
       at System.Windows.Window.CreateSourceWindowDuringShow()
       at System.Windows.Window.SafeCreateWindowDuringShow()
       at System.Windows.Window.ShowHelper(Object booleanBox)
       at System.Windows.Window.Show()



    This isn't happening if we are binding to a Name/Value pair only when we are binding directly to objects and only using a DisplayMemberPath. 

    Thanks for any suggestions!
  2. Konstantina
    Admin
    Konstantina avatar
    2332 posts

    Posted 17 Aug 2010 Link to this post

    Hello Damon,

    Thank you for contacting us.

    We are aware of this issue with RadComboBox. We are now working on it and a fix will be provided in the latest internal build this week, or next week at the latest.
    Sorry for the caused inconvenience.

    If you have any other questions about our controls please let us know.

    Sincerely yours,
    Konstantina
    the Telerik team
    Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Public Issue Tracking system and vote to affect the priority of the items
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  4. Damon
    Damon avatar
    4 posts
    Member since:
    Aug 2010

    Posted 18 Aug 2010 Link to this post

    Are there any known work arounds? So far not everyone on the team experiences this issue. 
  5. Konstantina
    Admin
    Konstantina avatar
    2332 posts

    Posted 19 Aug 2010 Link to this post

    Hi Damon,

    Thank you for getting back to us.

    The work around is to turn off the automation clients, for example the Narrator or the Audio Description from the Ease of Access Center of the Windows.

    Hope this helps. If you need further help please let us know.

    Greetings,
    Konstantina
    the Telerik team
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  6. Damon
    Damon avatar
    4 posts
    Member since:
    Aug 2010

    Posted 23 Aug 2010 Link to this post

    The latest internal build seems to correct this issue how ever i had nothing in the ease of access center active. Is there a signed hot fix available we can use for our publishes? The unlicensed nag screen prevents us from deploying any updates.
  7. Konstantina
    Admin
    Konstantina avatar
    2332 posts

    Posted 24 Aug 2010 Link to this post

    Hi Damon,

    The unlicensed screen is due to the trial version of the assemblies you are using. Once you purchase the controls and become our client, in your account will be available DEV assemblies for download, which you can use for publishing.

    If you have any other questions regarding our controls please feel free to contact us again.

    Regards,
    Konstantina
    the Telerik team
    Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Public Issue Tracking system and vote to affect the priority of the items
  8. Damon
    Damon avatar
    4 posts
    Member since:
    Aug 2010

    Posted 24 Aug 2010 Link to this post

    I have the licensed version but there is no hotfix available that is liscensed and i have no automation clients running so i can't use the paid version. I was inquiring when a hotifx would be available for download.
  9. Konstantina
    Admin
    Konstantina avatar
    2332 posts

    Posted 25 Aug 2010 Link to this post

    Hi Damon,

    Could you please give us the e-mail of the license holder or tell him to contact us. In that way we will be able to add you as a developer to this license and you will be able to download DEV versions and hotfixes of our controls.

    Looking forward to your reply.

    Best wishes,
    Konstantina
    the Telerik team
    Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Public Issue Tracking system and vote to affect the priority of the items
  10. Hung
    Hung avatar
    1 posts
    Member since:
    Sep 2010

    Posted 09 Sep 2010 Link to this post

    I'm license developer and I also get the same problem with Damon. Do you have any hotfix for licence version yet?

    Thanks
    Hung
  11. Valeri Hristov
    Admin
    Valeri Hristov avatar
    2252 posts

    Posted 10 Sep 2010 Link to this post

    Hello Hung,

    The DEV versions of the assemblies are available for evey internal build and service pack. As for the internal builds, you just need to make sure that you have downloaded the latest official service pack under the account you use.

    Kind regards,
    Valeri Hristov
    the Telerik team
    Do you want to have your say when we set our development plans? Do you want to know when a feature you care about is added or when a bug fixed? Explore the Telerik Public Issue Tracking system and vote to affect the priority of the items
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