Issue Refreshing Column Filters

[Matthew]

Hello,

I have a RadGridView with an ObservableCollection as it's ItemsSource.

The ObservableCollection holds a collection of objects similar in relation to sports players and teams.

where the Player object looks like:

ObservableCollection<Player> _players;

// Psuedo-code Object Descriptions
Player
{
    UniqueIdentifier (Guid)
    string Name
    Guid TeamID (FK to Team's UniqueIdentifier)
    string Position
    int Number
    //etc.
}

Team
{
    UniqueIdentifier (Guid)
    string Name
    string Location
    //etc.
}

<telerik:RadGridView>
    <telerik:RadGridView.Columns>
        <telerik:GridViewDataColumn Header="Team"
                            DataMemberBinding="{Binding Team.Name}" />
        <telerik:GridViewDataColumn Header="Name"
                            DataMemberBinding="{Binding Name}" />
        <telerik:GridViewDataColumn Header="Position"
                            DataMemberBinding="{Binding Position}" />
        <telerik:GridViewDataColumn Header="Number"
                            DataMemberBinding="{Binding Number}" />
    </telerik:RadGridView.Columns>
</telerik:RadGridView>

The RadGrid I have is displaying columns for all of the properties similar to the XAML posted above.

I query for all the Players, Including the Navigation Property for Team, asynchronously.  In the callback I call _players.Clear() and Add the results from the query to _players.

After the first query the column filters on the RadGridView work fine.  When I perform the Load operation again, and then click on the Filter icon on the Column with Header == "Team" the screen goes blank and I get this message in my output window:
"Binding cannot be changed after it has been used."

I've also seen this error when the site is deployed:

User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; WOW64; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; InfoPath.3; .NET4.0C; BRI/2; MS-RTC LM 8)

Timestamp: Mon, 30 Jan 2012 20:08:56 UTC

Message: Unhandled Error in Silverlight Application [Binding_CannotBeChangedAfterUse]

Arguments:

Debugging resource strings are unavailable. Often the key and arguments provide sufficient information to diagnose the problem. See http://go.microsoft.com/fwlink/?linkid=106663&Version=4.0.60831.0&File=System.Windows.dll&Key=Binding_CannotBeChangedAfterUse  
   at System.Windows.Data.BindingBase.CheckSealed()

   at Telerik.Windows.Data.DataFieldDescriptorExtensions.PrepareBinding(IDataFieldDescriptor fieldDescriptor, Binding memberBinding)

   at Telerik.Windows.Data.DataFieldDescriptorExtensions.CreateConvertedAndFormattedValueFunc(IDataFieldDescriptor fieldDescriptor, Func`2 func)

   at Telerik.Windows.Controls.GridView.FilteringViewModel.InitializeConvertedAndFormattedValueFunc()

   at Telerik.Windows.Controls.GridView.FilteringViewModel.CreateDistinctValueViewModel(Object distinctValue)

   at Telerik.Windows.Controls.GridView.DistinctValueViewModelCollection.AddRangeFromSource(IEnumerable source)

   at Telerik.Windows.Controls.GridView.DistinctValueViewModelCollection.SetSource(IEnumerable source, Func`2 createDistinctValueCallback)

I managed to work around this problem by creating a property (and binding to it instead) on my Player BO similar to:

public string TeamName
{
    get { return this.Team == null ? string.Empty : this.Team.Name; }
}

[Rossen Hristov]

Hi,

What version of our controls are you using?

Can you send us a dummy sample project that reproduces this exception and we will debug it immediately.

Thanks in advance.

Regards,
Ross
the Telerik team

[Matthew]

I'm using Version: 2011.3.1116.1040

I have been unable to reproduce this issue outside my project. It's possible that there is something I am doing while populating the ObservableCollection is causing this problem, but my theory is that it has something to do with how the NavigationProperty is populating.

Sorry I cannot be of more help. I have a workaround I'm willing to live with and don't have a lot of time to spend trying to figure out what's actually going on.