Weird exception when viewing design

[Tony]

I've got a window that contains a RadSplitButton control in it.  Here's a snippet of the code surrounding the RadSplitButton:

<Window x:Class="CarSystem.AlarmsDialog"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:telerik="http://schemas.telerik.com/2008/xaml/presentation"
        xmlns:c="clr-namespace:CarSystem"
        xmlns:cc="clr-namespace:CarSystem.CustomControls;assembly=CustomControls"
        xmlns:tl="clr-namespace:Telerik.Windows.Controls;assembly=Telerik.Windows.Controls.Navigation"
        Background="Transparent"
        BorderBrush="Black"
        BorderThickness="5"
        Closing="Window_Closing"
        Foreground="White"
        HorizontalAlignment="Center"
        Height="890"
        Icon=". . .
        Loaded="Window_Loaded"
        ResizeMode="CanMinimize"
        Title=". . ."
        VerticalAlignment="Center"
        Width="890"
        WindowStartupLocation="CenterScreen"
        WindowStyle="None">

    <StackPanel Background="#FF3C4B66">

    . . .

                <StackPanel FocusManager.IsFocusScope="true" HorizontalAlignment="Right" Orientation="Horizontal" >
                    <Button Background="{DynamicResource ButtonBackground}"
                            Click="CorrectButton_Click"
                            Content="CORRECT"
                            FontSize="20"
                            FontWeight="Bold"
                            Foreground="{DynamicResource ButtonForeground}"
                            Height="60"
                            HorizontalAlignment="Right"
                            Margin="10"
                            Name="CorrectButton"
                            Width="156"
                            VerticalAlignment="Center" />
                    <telerik:RadSplitButton Background="{DynamicResource ButtonBackground}"
                                            Click="MisreadButton_Click"
                                            CloseOnEscape="False"
                                            Content="INCORRECT"
                                            DropDownIndicatorVisibility="Visible"
                                            DropDownPlacement="Top"
                                            FontSize="20"
                                            FontWeight="Bold"
                                            Foreground="{DynamicResource ButtonForeground}"
                                            Height="60"
                                            HorizontalAlignment="Right"
                                            Margin="10"
                                            Name="IncorrectButton"
                                            Style="{StaticResource RadSplitButtonStyle1}"
                                            VerticalAlignment="Center"
                                            Width="200">
                        <telerik:RadSplitButton.DropDownContent>
                            <tl:RadContextMenu>
                                <tl:RadMenuItem Header="DEFER (8 hrs)" Click="DeferAlarm_Click" />
                                <tl:RadMenuItem Header="MISREAD" Click="MisreadAlarm_Click" />
                                <tl:RadMenuItem Header="NO PLATE" Click="NoPlate_Click" />
                                <tl:RadMenuItem Header="HL ENTRY EXPIRED" Click="ExpiredHLEntry_Click" />
                                <tl:RadMenuItem Header="WRONG STATE" Click="WrongState_Click" />
                                <tl:RadMenuItem Header="UNKNOWN" Click="Unknown_Click" />
                            </tl:RadContextMenu>
                        </telerik:RadSplitButton.DropDownContent>
                    </telerik:RadSplitButton>


                </StackPanel>
            </StackPanel>

    . . .

    </StackPanel>
</Window>

When the program runs, everything works fine and the window displays without any errors.  But, when I view the window in the Designer panel in Visual Studio 2010, an exception is reported!

Here's the exception that appears instead of the rendering of the window:

 

System.Reflection.TargetInvocationException

Exception has been thrown by the target of an invocation.

at System.RuntimeMethodHandle._InvokeMethodFast(IRuntimeMethodInfo method, Object target, Object[] arguments, SignatureStruct& sig, MethodAttributes methodAttributes, RuntimeType typeOwner) at System.RuntimeMethodHandle.InvokeMethodFast(IRuntimeMethodInfo method, Object target, Object[] arguments, Signature sig, MethodAttributes methodAttributes, RuntimeType typeOwner) at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture, Boolean skipVisibilityChecks) at System.Delegate.DynamicInvokeImpl(Object[] args) 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)



System.Windows.Markup.XamlParseException

Failed to create a 'Path' from the text '(my:RadSplitButton.ToggleContentRotateAngle)'.

at System.Windows.Markup.XamlReader.RewrapException(Exception e, Uri baseUri) at System.Windows.FrameworkTemplate.LoadTemplateXaml(XamlReader templateReader, XamlObjectWriter currentWriter) at System.Windows.FrameworkTemplate.LoadTemplateXaml(XamlObjectWriter objectWriter) at System.Windows.FrameworkTemplate.LoadOptimizedTemplateContent(DependencyObject container, IComponentConnector componentConnector, IStyleConnector styleConnector, List`1 affectedChildren, UncommonField`1 templatedNonFeChildrenField) at System.Windows.FrameworkTemplate.LoadContent(DependencyObject container, List`1 affectedChildren) at System.Windows.StyleHelper.ApplyTemplateContent(UncommonField`1 dataField, DependencyObject container, FrameworkElementFactory templateRoot, Int32 lastChildIndex, HybridDictionary childIndexFromChildID, FrameworkTemplate frameworkTemplate) at System.Windows.FrameworkTemplate.ApplyTemplateContent(UncommonField`1 templateDataField, FrameworkElement container) at System.Windows.FrameworkElement.ApplyTemplate() at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) at System.Windows.Controls.Grid.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Grid.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Control.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.StackPanel.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.StackPanel.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) at System.Windows.Controls.Grid.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.StackPanel.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) at System.Windows.Controls.ContentPresenter.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Grid.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Border.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Control.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Documents.AdornerDecorator.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) at System.Windows.Controls.Grid.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Border.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Border.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.DockPanel.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Border.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Grid.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Control.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Border.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at MS.Internal.Designer.ZoomableViewPresenter.DesignerBackground.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at Microsoft.Windows.Design.Interaction.DesignerView.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at MS.Internal.Designer.Viewport.MeasureOverride(Size availableSize) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) at System.Windows.Controls.ScrollContentPresenter.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Grid.MeasureCell(Int32 cell, Boolean forceInfinityV) at System.Windows.Controls.Grid.MeasureCellsGroup(Int32 cellsHead, Size referenceSize, Boolean ignoreDesiredSizeU, Boolean forceInfinityV) at System.Windows.Controls.Grid.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.ScrollViewer.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Grid.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at MS.Internal.Helper.MeasureElementWithSingleChild(UIElement element, Size constraint) at System.Windows.Controls.ContentPresenter.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Controls.Control.MeasureOverride(Size constraint) at System.Windows.FrameworkElement.MeasureCore(Size availableSize) at System.Windows.UIElement.Measure(Size availableSize) at System.Windows.Interop.HwndSource.SetLayoutSize() at System.Windows.Interop.HwndSource.set_RootVisualInternal(Visual value) at MS.Internal.DeferredHwndSource.ProcessQueue(Object sender, EventArgs e)



System.Xaml.XamlParseException

Prefix 'my' does not map to a namespace.

at MS.Internal.Xaml.XamlContext.ResolveXamlType(String qName, Boolean skipVisibilityCheck) at MS.Internal.Xaml.Context.ObjectWriterContext.ServiceProvider_Resolve(String qName) at MS.Internal.Xaml.ServiceProviderContext.System.Windows.Markup.IXamlTypeResolver.Resolve(String qName) at System.Windows.PropertyPath.GetTypeFromName(String name, Object context) at System.Windows.PropertyPath.ResolvePropertyName(String name, Object item, Type ownerType, Object context, Boolean throwOnError) at System.Windows.PropertyPath.ResolvePathParts(ITypeDescriptorContext typeDescriptorContext) at System.Windows.PropertyPath.PrepareSourceValueInfo(ITypeDescriptorContext typeDescriptorContext) at System.Windows.PropertyPath..ctor(String path, ITypeDescriptorContext typeDescriptorContext) at System.Windows.PropertyPathConverter.ConvertFrom(ITypeDescriptorContext typeDescriptorContext, CultureInfo cultureInfo, Object source) at MS.Internal.Xaml.Runtime.ClrObjectRuntime.CreateObjectWithTypeConverter(ServiceProviderContext serviceContext, XamlValueConverter`1 ts, Object value) at MS.Internal.Xaml.Runtime.ClrObjectRuntime.CreateFromValue(ServiceProviderContext serviceContext, XamlValueConverter`1 ts, Object value, XamlMember property) at System.Xaml.XamlObjectWriter.Logic_CreateFromValue(ObjectWriterContext ctx, XamlValueConverter`1 typeConverter, Object value, XamlMember property, String targetName, IAddLineInfo lineInfo)

Does anyone have any explanation for what's going on?  I'm not using the "my" prefix anywhere in my code.

Tony

[Petar Mladenov]

Hello Tony,

 We weren't able to reproduce such exception. Could you please examine our test project and let us know if we have missed something? Thank you in advance.

All the best,
Petar Mladenov
the Telerik team