d:DesignData issue, Visual Studio 2010 cant build after adding sample design data with Expression Blend 4

Question

Hi,

VS 2010 solution and Silverlight project builds fine, then:

1. I open MyView.xaml view in Expression Blend 4
2. Add sample data from class (I use my class defined in the same project)

after I add new sample design data with Expression blend 4, everything looks fine, you see the added sample data in the EB 4 fine, you also see the data in VS 2010 designer too.

Close the EB 4, and next VS 2010 build is giving me this errors:

 Error 7 XAML Namespace http://schemas.microsoft.com/expression/blend/2008 is not resolved. C:\Code\source\...myview.xaml

and:

Error 12 Object reference not set to an instance of an object. ... TestSampleData.xaml

when I open the TestSampleData.xaml I see that namespace for my class used to define sample data is not recognized.

However this namespace and the class itself exist in the same project!

If I remove the design data from the MyView.xaml:

d:DataContext="{d:DesignData /SampleData/TestSampleData.xaml}"

it builds fine and the namespace in TestSampleData.xaml is recognized this time?? and then if add:

d:DataContext="{d:DesignData /SampleData/TestSampleData.xaml}" 

I again see in the VS 2010 designer sample data, but the next build fails and again I see studio cant find the namespace in my TestSampleData.xaml containing sample data.

That cycle is driving me crazy. Am I missing something here, is it not possible to have your class defining sample design data in the same project you have the MyView.xaml view??

cheers Valko

Answer 1

I know this is and old question, but do you have the line mc:Ignorable="d" in your xaml? Without this line you will get this error.