wpf class library with resource dictionary

Question

Is it possible to have a resource dictionary in a WPF class library assembly (.dll)? I ask this because I have an "Application WPF" assembly (.exe), if I try to turn the type of the assembly to "WPF Class Library" I get the error:

Impossible to specify the element ApplicationDefinition in the project file of the Library

How can I make it work?

Answer 1

This will be the build action of one of your XAML files. I would use a WPF User Control Library or WPF Custom Control Library instead of a general class library.

Answer 2

You get that error because one of your XAML files has a Build Action set to ApplicationDefinition. Usually, that is App.xaml. Remove that file or change it's Build Action from Properties Window to Page to stop getting that error.