c# - Loading merged ResourceDictionary from different assembly fails

Question

I've put all of my application's ResourceDictionaries into a separate assembly and merged them into one ResourceDictionary which I want to include as a resource in my application:

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <ResourceDictionary.MergedDictionaries>
        <ResourceDictionary Source="InputStyles.xaml"/>
        <ResourceDictionary Source="DataGridStyles.xaml"/>
        <ResourceDictionary Source="ComboboxStyles.xaml"/>
        <ResourceDictionary Source="CheckboxStyles.xaml"/>
        <ResourceDictionary Source="TabControlStyles.xaml"/>
        <ResourceDictionary Source="ButtonStyles.xaml"/>
    </ResourceDictionary.MergedDictionaries>
</ResourceDictionary>

Declaring resource:

<Window.Resources>
    <ResourceDictionary Source="pack://application:,,,/StyleAssembly;component/Styles.xaml"/>
</Window.Resources>

Looking at the designer in VS all controls are displayed with the styles from the files but when I try to start the application I'm getting the following error:

"Cannot locate resource 'inputstyles.xaml'."

The build action is set to 'Page' for all files and the build for both projects succeeds. What am I doing wrong?

Answer 1

The build action should be defined as Resource or Content if you are willing to do some of the leg work.

Your resource must be defined as part of the project as a Resource build action. If you include a resource .xaml file in the project as Resource, you do not need to copy the resource file to the output directory, the resource is already included within the compiled application. You can also use Content build action, but you must then copy the files to the output directory and also deploy the resource files in the same path relationship to the executable.