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POSilverlight Xaml Editor error when inheriting from a custom class
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  1. POSilverlight Xaml Editor error when inheriting from a custom class
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    copied!<p>I've created an abstract class which inherits from UserControl, and has an abstract method. I have a couple controls implementing this abstract class. The Silverlight control runs fine, but in the XAML editor, I get an InstanceBuilderException thrown, and thus it won't let me view the XAML preview. Is there a way to get around this, or am I just doing something wrong? Thanks!</p> <p>The abstract class is very simple:</p> <pre><code>public abstract class Widget : UserControl { public abstract void Close(); } </code></pre> <p>The implementation is here:</p> <pre><code>public partial class OnlineUserWidget : Widget { ..... } </code></pre> <p>And the XAML</p> <pre><code>&lt;local:Widget x:Class="Prototype.Widgets.OnlineUserWidget" xmlns:local="clr-namespace:Prototype.Widgets" .... &lt;/local:Widget&gt; </code></pre> <p>Finally the error: </p> <p>Cannot create an instance of "Widget". at Microsoft.Expression.DesignModel.Core.InstanceBuilderOperations.InstantiateType(Type type, Boolean supportInternal, Boolean supportProtected) at Microsoft.Expression.DesignModel.InstanceBuilders.ClrObjectInstanceBuilder.InstantiateTargetType(IInstanceBuilderContext context, ViewNode viewNode) at Microsoft.Expression.DesignModel.InstanceBuilders.ClrObjectInstanceBuilder.Instantiate(IInstanceBuilderContext context, ViewNode viewNode) at Microsoft.Expression.Platform.Silverlight.InstanceBuilders.DependencyObjectInstanceBuilder.Instantiate(IInstanceBuilderContext context, ViewNode viewNode) at Microsoft.Expression.Platform.Silverlight.InstanceBuilders.FrameworkElementInstanceBuilder.Instantiate(IInstanceBuilderContext context, ViewNode viewNode) at Microsoft.Expression.Platform.Silverlight.InstanceBuilders.UserControlInstanceBuilder.Instantiate(IInstanceBuilderContext context, ViewNode viewNode) at MS.Internal.Services.DesignModeValueProviderService.DesignModeValueProviderBuilder.Instantiate(IInstanceBuilderContext context, ViewNode viewNode) at Microsoft.Expression.DesignModel.Core.ViewNodeManager.Instantiate(ViewNode viewNode)</p>
 

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