Silverlight 4 ManagedRuntimeError 4004 Listbox Scrolling Image XamlParseException

Silverlight 4 is crashing on me. The Just-In-Time Debugger says:

An unhandled exception ('Unhandled Error in Silverlight Application')

Code: 4004

Category: ManagedRuntimeError

Message: System.Windows.Markup.XamlparseException: [Line: 0 Position: 0]

I bind a listbox to a collection of 20 (or so) items. the collection loads fine and binds correctly. However, when I scroll to the bottom of the collection and then try to scroll back up silverlight crashes.

The error only occurs when I include a contentcontrol, contentpresenter, or an image control within my Item Template. For instance, If I set the 'InnerBorder' height to 100 and remove the content control silverlight will not crash. Furthermore The {Binding Visual} is a image defined on the item's view model.

Here is my code.

  <Border HorizontalAlignment="Left"
            Margin="2"
            Padding="0">
        <Controls:Expander ExpandDirection="Right"
                           Header="Templates">                
            <ListBox UseLayoutRounding="False" 
                     SelectedItem="{Binding SelectedTemplate, Mode=TwoWay}"
                     Margin="4"
                     ItemsSource="{Binding Templates}"
                     ScrollViewer.VerticalScrollBarVisibility="Visible"
                     Width="250">
                <ListBox.ItemTemplate>
                    <DataTemplate>
                        <Border Style="{StaticResource InnerBorder}"
                                Width="200"
                                Margin="4">
                            <ToolTipService.ToolTip>
                                <ToolTip Content="{Binding Description}" />
                            </ToolTipService.ToolTip>
                            <StackPanel Orientation="Vertical"
                                        VerticalAlignment="Center"
                                        HorizontalAlignment="Center">

                                <ContentControl Content="{Binding Visual}"
                                                MaxWidth="100" />

                                <TextBlock Text="{Binding Name}"
                            开发者_如何学C               HorizontalAlignment="Center" />
                            </StackPanel>
                        </Border>
                    </DataTemplate>
                </ListBox.ItemTemplate>
            </ListBox>
        </Controls:Expander>

Im totally lost. Any help would be greatly appreciated.

I was having this same issue. I managed to track it down to the ToolTipService. If I scroll while a tooltip is displayed, the crash occurs (only on some items). If I remove the tooltip binding, this issue goes away.

I have not yet resolved that problem so that tooltips can be displayed, but at least I can remove the crash.

Update
I managed to resolve the problem and keep tooltips working. Like you, I was directly setting the tooltip content to some text. Instead, I actually set the content to a StackPanel containing a TextBlock that then contained the text and now it works without crashing. I am not entirely sure why this works, unfortunately.