URI prefix is not recognized when setting the source of a resourcedictionary

Question

The URI prefix is not recognized

I am getting the above error message in a System.NotSupportedException.

This line is used to set the source of a ResourceDictionary:

view.Source = new Uri("/DA.EasyTeach.Math;component/View.xaml", UriKind.RelativeOrAbsolute);

This is a snip of my file structure:

View.xaml has a Build Action of Resource.

Try `new Uri("pack://application:,,,/DA.EasyTeach.Math;component/View.xaml")` without UriKind. See [Resource File Pack URIs](https://msdn.microsoft.com/en-us/library/aa970069(v=vs.100).aspx#Resource_File_Pack_URIs___Local_Assembly). Also make sure that `DA.EasyTeach.Math` is an assembly name, not a namespace. — Clemens, Apr 14 '16 at 10:38
@Clemens It's a `ResourceDictionary`, not `Frame`. `View.xaml` contains a `DataTemplate`. — afaolek, Apr 14 '16 at 11:12

score 6 · Answer 1 · edited May 23 '17 at 11:47

6

I have a hybrid application WinForms + WPF and the cause was System.Windows.Application.Current == null. Based on this question I solved it by running following line before creating dictionary Uri:

new System.Windows.Application();

edited May 23 '17 at 11:47

Community

1
1

answered May 11 '17 at 07:32

Jan Zahradník

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score 0 · Answer 2 · answered Apr 18 '16 at 08:45

I finally discovered that the issue was not about the Uri. The ResourceDictionary was part of a plugin for a MEF application. I only had to merge the ResourceDictionary with the resources in the host. Solved!

I'm only putting this as an answer since it could help someone else.

score 0 · Answer 3 · answered Oct 12 '20 at 19:12

Probably it could happen when you use multi-windowed application.

So in such case the possible solution can be to set Application shutdown mode:

public AppConstuctor()
{
    ShutdownMode = ShutdownMode.OnExplicitShutdown;
}

or in xaml:

<Application ...
             ShutdownMode="OnExplicitShutdown">
...
</Application>

URI prefix is not recognized when setting the source of a resourcedictionary

3 Answers3