Silverlight: Fixing the "Tag Expander Does Not Exist" Compiler Error
If you create a new Silverlight Navigation project, then compile immediately with no changes, you will get the following compiler error:
The tag 'Expander' does not exist in XML namespace 'clr-namespace:System.Windows.Controls;assenbly=System.Windows.Controls'
This is because the Expander element (as well as DockPanel, WrapPanel, HeaderedContentControl, Viewbox, and DataForm have been moved to the Silverlight Toolkit.
To fix this problem:
1. If you haven't already done so, download and install the Silverlight Toolkit (http://www.codeplex.com/Silverlight)
2. Add the System.Windows.Controls.Toolkit assembly to your project
3. Add the following namespace reference to the top of your project's ErrorWindow.xaml file:
xmlns:controlsToolkit="clr-namespace:System.Windows.Controls;assembly=System.Windows.Controls.Toolkit"4.
4. In the body of the ErrorWindow.xaml file, change the prefix of the Expander control from "controls" to "controlsToolkit". Remember to do this on both the opening and closing tags:
<controlsToolkit:Expander Grid.Row="2" Header="Details" Margin="0, 10, 0, 0" >
<TextBox Text="{Binding ErrorDetails}"
Height="100"
TextWrapping="Wrap" IsReadOnly="True"
VerticalScrollBarVisibility="Auto" />
</controlsToolkit:Expander>
Best Regards,
Kevin McNeish
INETA Speaker
Chieft Architect, MM .NET Application Framework
www.oakleafsd.com