Related to my previous question: http://stackoverflow.com/questions/855519/binding-combobox-selecteditem-in-silverlight
I have a ComboBox bound like so:
<ComboBox x:Name="PART_CommentaryList"
HorizontalAlignment="Left"
Margin="3"
ItemsSource="{Binding Path=CurrentVideo.Commentaries}"
SelectedItem="{Binding Path=CurrentCommentary, Mode=TwoWay}">
Both the CurrentVideo and CurrentCommentary property change regularly. After a few times, I get this error:
Category: ManagedRuntimeError
Message: System.ArgumentException: Value does not fall within the expected
range.
at MS.Internal.XcpImports.MethodEx(IntPtr ptr, String name,
CValue[] cvData)
at MS.Internal.XcpImports.MethodPack(IntPtr objectPtr, String methodName,
Object[] rawData)
at MS.Internal.XcpImports.UIElement_TransformToVisual(UIElement element,
UIElement visual)
at System.Windows.UIElement.TransformToVisual(UIElement visual)
at System.Windows.Controls.Primitives.Selector.IsOnCurrentPage(
Int32 index, Rect& itemsHostRect, Rect& listBoxItemRect)
at System.Windows.Controls.Primitives.Selector.ScrollIntoView(
Int32 index)
at System.Windows.Controls.Primitives.Selector.SetFocusedItem(
Int32 index, Boolean scrollIntoView)
at System.Windows.Controls.ComboBox.PrepareContainerForItemOverride(
DependencyObject element, Object item)
at System.Windows.Controls.ItemsControl.UpdateContainerForItem(
Int32 index)
at System.Windows.Controls.ItemsControl.RecreateVisualChildren()
at System.Windows.Controls.ItemsControl.RecreateVisualChildren(
IntPtr unmanagedObj)
This seems like a ComboBox bug to me. I can verify that CurrentVideo changes before CurrentCommentary, so the selected item should always be an item which is in the list.
Related, I really don't want the Mode=TwoWay, because when the ItemsSource is changed, the SelectedItem is temporarily null, which gets set back in my model, which I don't actually want. But the binding doesn't work at all otherwise (which seems like another bug).