Use an External ResourceDictionary in a WindowsPhone 7 app

Question

I am trying to create an ResourceFile Called DataTemplate.xaml in an external dll and use that in a WP7 page. When I do the following in the header of my Page I get an erro

Answer 1

I tried the pack syntax while trying to share XAML ResourceDictionary files and got the same error message. I ended up using this syntax and it worked for me.

<Application.Resources>
    <ResourceDictionary>
        <ResourceDictionary.MergedDictionaries>
            <ResourceDictionary Source="/MyDLLName;component/Folder/MyXAMLFile.xaml"/>                
        </ResourceDictionary.MergedDictionaries>
    </ResourceDictionary>
</Application.Resources>

Answer 2

Silverlight doesn't support pack URIs. It's a WPF feature.

If you examine the type of the Source property for the Image object in Silverlight it is Uri. But in WPF the source is a dependency property with a type of ImageSource.

Answer 3

I've managed to get this to work using the following steps:

1. Created a standard WP7 application using the "Windows Phone Application" application template called "WP7ExternalResourcesTest".
2. Added a project to the same solution using the "Windows Phone Class Library" template called "WP7ExternalResourcesTestLibrary".
3. Removed the default Class.cs file form the library project.
4. Added a file called "External.xaml" using the "XML file" template and set the "Build Action" to "Page".

5. Added the following XAML to the new XAML file:

   <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                       xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
       <SolidColorBrush x:Key="ForegroundBrush" Color="Red" />
   </ResourceDictionary>
   

6. Built the library project, and then added a reference to it from the WP7ExternalResourcesTest project.

7. In WP7ExternalResourcesTest, opened App.xaml and changed the Application.Resources section to the following:

   <Application.Resources>
       <ResourceDictionary>
           <ResourceDictionary.MergedDictionaries>
               <ResourceDictionary Source="/WP7ExternalResourcesTestLibrary;component/External.xaml" />
           </ResourceDictionary.MergedDictionaries>
       </ResourceDictionary>
   </Application.Resources>
   

8. In MainPage.xaml, added Foreground="{StaticResource ForegroundBrush}" to the TextBlock named "PageTitle".
9. Ran the application in the emulator. The end result was that the TextBlock correctly displayed the words "page name" in red.

Hope this helps.