InvalidOperationException when Scrolling DataGrid: The binding expression already belongs to a BindingGroup

Question

When trying to scroll down on a DataGrid, I'm getting an InvalidOperationException stating, "The binding expression already belongs to a BindingGroup; it cannot be added to a different BindingGroup". I don't know of any BindingGroups in use so I'm not really sure what it's talking about. I've narrowed it down to occurring with only the column below. I suspect it also has to do with virtualization. Any ideas?

Here is the DataGrid markup:

<DataGrid x:Name="dgStudentSNP" 
              AutoGenerateColumns="False"

              Grid.Row="1" Margin="6,10" 
              HorizontalAlignment="Stretch"
              HeadersVisibility="Column"
              CanUserSortColumns="True"
              CanUserAddRows="False"
              CanUserResizeColumns="True"
              CanUserDeleteRows="False"
              BorderThickness="1"
              SelectedValuePath="SNPEnrollmentID" VerticalScrollBarVisibility="Auto" VerticalAlignment="Top" Height="Auto" IsReadOnly="True">
            <DataGrid.Columns>
                <DataGridTemplateColumn Header="Student Name" MinWidth="120">
                    <DataGridTemplateColumn.CellTemplate>
                        <DataTemplate>
                            <TextBlock>
                                    <Hyperlink Click="GetStudentFamily" >
                                        <Run>
                                            <Run.Text >
                                                <MultiBinding StringFormat="{}{0} {1}">
                                                    <Binding Path="FirstName"/>
                                                    <Binding Path="LastName" />
                                                </MultiBinding>
                                            </Run.Text>                                                              
                                        </Run>
                                    </Hyperlink>
                            </TextBlock>
                        </DataTemplate>
                    </DataGridTemplateColumn.CellTemplate>
                </DataGridTemplateColumn>
              </DataGrid.Columns>
            </DataGrid>

Here is the stack trace for the exception:

Stack Trace :    at System.Windows.Data.BindingExpressionBase.JoinBindingGroup(BindingGroup bg, Boolean explicitJoin)
   at System.Windows.Data.BindingExpressionBase.RejoinBindingGroup(Boolean isReflective, DependencyObject contextElement)
   at System.Windows.Data.BindingExpression.OnDataContextChanged(DependencyObject contextElement)
   at System.Windows.Data.BindingExpression.HandlePropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.Data.BindingExpressionBase.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.Data.BindingExpression.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.Data.MultiBindingExpression.HandlePropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.Data.BindingExpressionBase.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.DependentList.InvalidateDependents(DependencyObject source, DependencyPropertyChangedEventArgs sourceArgs)
   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.TreeWalkHelper.OnInheritablePropertyChanged(DependencyObject d, InheritablePropertyChangeInfo info)
   at System.Windows.DescendentsWalker`1._VisitNode(DependencyObject d)
   at System.Windows.DescendentsWalker`1.VisitNode(DependencyObject d)
   at System.Windows.DescendentsWalker`1.WalkLogicalChildren(FrameworkElement feParent, FrameworkContentElement fceParent, IEnumerator logicalChildren)
   at System.Windows.DescendentsWalker`1.IterateChildren(DependencyObject d)
   at System.Windows.DescendentsWalker`1._VisitNode(DependencyObject d)
   at System.Windows.DescendentsWalker`1.VisitNode(DependencyObject d)
   at System.Windows.DescendentsWalker`1.WalkLogicalChildren(FrameworkElement feParent, FrameworkContentElement fceParent, IEnumerator logicalChildren)
   at System.Windows.DescendentsWalker`1.WalkFrameworkElementLogicalThenVisualChildren(FrameworkElement feParent, Boolean hasLogicalChildren)
   at System.Windows.DescendentsWalker`1.IterateChildren(DependencyObject d)
   at System.Windows.DescendentsWalker`1._VisitNode(DependencyObject d)
   at System.Windows.DescendentsWalker`1.VisitNode(FrameworkElement fe)
   at System.Windows.DescendentsWalker`1.VisitNode(DependencyObject d)
   at System.Windows.DescendentsWalker`1.WalkFrameworkElementLogicalThenVisualChildren(FrameworkElement feParent, Boolean hasLogicalChildren)
   at System.Windows.DescendentsWalker`1.IterateChildren(DependencyObject d)
   at System.Windows.DescendentsWalker`1.StartWalk(DependencyObject startNode, Boolean skipStartNode)
   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.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal)
   at System.Windows.Controls.ContentPresenter.OnContentChanged(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.OnDataContextChanged(DependencyObject contextElement)
   at System.Windows.Data.BindingExpression.HandlePropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.Data.BindingExpressionBase.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.Data.BindingExpression.OnPropertyInvalidation(DependencyObject d, DependencyPropertyChangedEventArgs args)
   at System.Windows.DependentList.InvalidateDependents(DependencyObject source, DependencyPropertyChangedEventArgs sourceArgs)
   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.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal)
   at System.Windows.Controls.ItemContainerGenerator.LinkContainerToItem(DependencyObject container, Object item, Boolean isRecycled)
   at System.Windows.Controls.ItemContainerGenerator.OnItemReplaced(Object oldItem, Object newItem, Int32 index)
   at System.Windows.Controls.ItemContainerGenerator.OnCollectionChanged(Object sender, NotifyCollectionChangedEventArgs args)
   at System.Windows.Controls.ItemContainerGenerator.System.Windows.IWeakEventListener.ReceiveWeakEvent(Type managerType, Object sender, EventArgs e)
   at System.Windows.WeakEventManager.DeliverEventToList(Object sender, EventArgs args, ListenerList list)
   at System.Windows.WeakEventManager.DeliverEvent(Object sender, EventArgs args)
   at System.Collections.Specialized.CollectionChangedEventManager.OnCollectionChanged(Object sender, NotifyCollectionChangedEventArgs args)
   at System.Collections.Specialized.NotifyCollectionChangedEventHandler.Invoke(Object sender, NotifyCollectionChangedEventArgs e)
   at System.Windows.Data.CollectionView.OnCollectionChanged(NotifyCollectionChangedEventArgs args)
   at System.Windows.Controls.ItemCollection.System.Windows.IWeakEventListener.ReceiveWeakEvent(Type managerType, Object sender, EventArgs e)
   at System.Windows.WeakEventManager.DeliverEventToList(Object sender, EventArgs args, ListenerList list)
   at System.Windows.WeakEventManager.DeliverEvent(Object sender, EventArgs args)
   at System.Collections.Specialized.CollectionChangedEventManager.OnCollectionChanged(Object sender, NotifyCollectionChangedEventArgs args)
   at System.Windows.Data.CollectionView.OnCollectionChanged(NotifyCollectionChangedEventArgs args)
   at System.Windows.Data.ListCollectionView.ProcessCollectionChangedWithAdjustedIndex(NotifyCollectionChangedEventArgs args, Int32 adjustedOldIndex, Int32 adjustedNewIndex)
   at System.Windows.Data.ListCollectionView.ProcessCollectionChanged(NotifyCollectionChangedEventArgs args)
   at System.Windows.Data.CollectionView.OnCollectionChanged(Object sender, NotifyCollectionChangedEventArgs args)
   at System.Windows.Controls.MultipleCopiesCollection.OnCollectionChanged(NotifyCollectionChangedEventArgs e)
   at System.Windows.Controls.MultipleCopiesCollection.set_CopiedItem(Object value)
   at System.Windows.Controls.Primitives.DataGridCellsPresenter.OnItemChanged(Object oldItem, Object newItem)
   at System.Windows.Controls.DataGridRow.OnItemChanged(Object oldItem, Object newItem)
   at System.Windows.Controls.DataGridRow.NotifyPropertyChanged(DependencyObject d, String propertyName, DependencyPropertyChangedEventArgs e, DataGridNotificationTarget target)
   at System.Windows.Controls.DataGridRow.OnNotifyRowPropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
   at System.Windows.DependencyObject.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
   at System.Windows.FrameworkElement.OnPropertyChanged(DependencyPropertyChangedEventArgs e)
   at System.Windows.Controls.DataGridRow.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.SetValueCommon(DependencyProperty dp, Object value, PropertyMetadata metadata, Boolean coerceWithDeferredReference, Boolean coerceWithCurrentValue, OperationType operationType, Boolean isInternal)
   at System.Windows.DependencyObject.SetValue(DependencyProperty dp, Object value)
   at System.Windows.Controls.DataGridRow.PrepareRow(Object item, DataGrid owningDataGrid)
   at System.Windows.Controls.DataGrid.PrepareContainerForItemOverride(DependencyObject element, Object item)
   at System.Windows.Controls.ItemsControl.MS.Internal.Controls.IGeneratorHost.PrepareItemContainer(DependencyObject container, Object item)
   at System.Windows.Controls.ItemContainerGenerator.System.Windows.Controls.Primitives.IItemContainerGenerator.PrepareItemContainer(DependencyObject container)
   at System.Windows.Controls.VirtualizingStackPanel.InsertContainer(Int32 childIndex, UIElement container, Boolean isRecycled)
   at System.Windows.Controls.VirtualizingStackPanel.AddContainerFromGenerator(Int32 childIndex, UIElement child, Boolean newlyRealized)
   at System.Windows.Controls.VirtualizingStackPanel.MeasureOverride(Size constraint)
   at System.Windows.Controls.Primitives.DataGridRowsPresenter.MeasureOverride(Size constraint)
   at System.Windows.FrameworkElement.MeasureCore(Size availableSize)
   at System.Windows.UIElement.Measure(Size availableSize)
   at System.Windows.ContextLayoutManager.UpdateLayout()
   at System.Windows.ContextLayoutManager.UpdateLayoutCallback(Object arg)
   at System.Windows.Media.MediaContext.InvokeOnRenderCallback.DoWork()
   at System.Windows.Media.MediaContext.FireInvokeOnRenderCallbacks()
   at System.Windows.Media.MediaContext.RenderMessageHandlerCore(Object resizedCompositionTarget)
   at System.Windows.Media.MediaContext.RenderMessageHandler(Object resizedCompositionTarget)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.DispatcherOperation.InvokeImpl()
   at System.Windows.Threading.DispatcherOperation.InvokeInSecurityContext(Object state)
   at System.Threading.ExecutionContext.runTryCode(Object userData)
   at System.Runtime.CompilerServices.RuntimeHelpers.ExecuteCodeWithGuaranteedCleanup(TryCode code, CleanupCode backoutCode, Object userData)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean ignoreSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Windows.Threading.DispatcherOperation.Invoke()
   at System.Windows.Threading.Dispatcher.ProcessQueue()
   at System.Windows.Threading.Dispatcher.WndProcHook(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndWrapper.WndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam, Boolean& handled)
   at MS.Win32.HwndSubclass.DispatcherCallbackOperation(Object o)
   at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
   at MS.Internal.Threading.ExceptionFilterHelper.TryCatchWhen(Object source, Delegate method, Object args, Int32 numArgs, Delegate catchHandler)
   at System.Windows.Threading.Dispatcher.InvokeImpl(DispatcherPriority priority, TimeSpan timeout, Delegate method, Object args, Int32 numArgs)
   at MS.Win32.HwndSubclass.SubclassWndProc(IntPtr hwnd, Int32 msg, IntPtr wParam, IntPtr lParam)
   at MS.Win32.UnsafeNativeMethods.DispatchMessage(MSG& msg)
   at System.Windows.Threading.Dispatcher.PushFrameImpl(DispatcherFrame frame)
   at System.Windows.Threading.Dispatcher.PushFrame(DispatcherFrame frame)
   at System.Windows.Application.RunDispatcher(Object ignore)
   at System.Windows.Application.RunInternal(Window window)
   at System.Windows.Application.Run(Window window)
   at Oasis.App.Main()

Answer 1

I just ran into a similar problem, but didn't have a MultiBinding in my DataTable. In this case we had a classic Textblock Run with a binding that was not set to Mode=OneWay yet. It didn't cause an error immediately (as is usual). The error only appeared when we started scrolling with the built in VerticalScrollBar when we limited the Height. Hope this is useful to someone else who lands here.

Answer 2

Setting the BindingGroupName to null does indeed work. This is mysterious to me and I wish someone else who understood what was going on a little better would post an answer. But, in the documentation eran otzap posted above:

http://msdn.microsoft.com/en-us/library/system.windows.data.bindinggroup.aspx

It says the following:

You set the BindingGroup property on FrameworkElement or FrameworkContentElement. Child elements inherit the BindingGroup from their parent elements, just as with any other inheritable property. A binding on a descendent element is added to a BindingGroup if one of the following situations occurs:

• The binding's source and the DataContext of the element that has the BindingGroup are the same object and the BindingGroupName property is not set.

• The BindingGroupName property of the binding is equal to the Name of the BindingGroup and they are not explicitly set to null. In the example of the address, suppose that the DataContext of the Panel is set to the object of type Address. The binding for each TextBox is added to the BindingGroup of the panel.

It would appear that when you use a multibinding in a datagrid the BindingGroup does not match the BindingGroupName for the binding, and so when you try to update those binding errors ensue.

The solution is to explicitly set the BindingGroupName of the MultiBinding to null like

   <MultiBinding StringFormat="{}{0} {1}" BindingGroupName="{x:Null}">
      <Binding Path="FirstName"/>
      <Binding Path="LastName" />
   </MultiBinding>

I have no idea what effect this will have later down the line but it makes this specific exception go away.