Xamarin: 'System.Resources.MissingManifestResourceException' on WinPhone - xamarin

Question

I found an issue with localization in WinPhone app. I added couple of resources and implemented localization. It is working fine in simulator, but crashing on Phone with exception Exception thrown: 'System.Resources.MissingManifestResourceException' in mscorlib.ni.dll
Any help?

Answer 1

Thanks to a bit of googling and a helpful blog post I have managed to solve this issue that happened intermittently with Xamarin.Forms projects.
This is the blog post that led me to the solution:
http://blog.tpcware.com/2016/06/xamarin-forms-localization/
Basically, the way you access resources on Android and iOS with Xamarin.Forms and Windows Phone is different:
To make it short, we need to “automagically” use the ResourceLoader.GetString(…) method when running on Store apps, while continuing to use the regular ResourceManager.GetString(…) method on all other platform. And because in the Xamarin Forms solution we use a resource file of type RESX, we also have the automatically generated resource class.
The super clever idea contained in the above linked post is to “hack” the resource class injecting a derived class of ResourceManager with an overridden GetString(…) method into the resource class “resourceMan” property (for a more detailed explanation of this hack, you can read the post).
We need to create our own version of ResourceManager like so and swap it for the existing ResourceManager using reflection:
public class WinRTResourceManager : ResourceManager
{
readonly ResourceLoader _resourceLoader;
private WinRTResourceManager(string baseName, Assembly assembly) : base(baseName, assembly)
{
_resourceLoader = ResourceLoader.GetForViewIndependentUse(baseName);
}
public static void InjectIntoResxGeneratedApplicationResourcesClass(Type resxGeneratedApplicationResourcesClass)
{
resxGeneratedApplicationResourcesClass
.GetRuntimeFields()
.First(m => m.Name == "resourceMan")
.SetValue(null, new WinRTResourceManager(
resxGeneratedApplicationResourcesClass.FullName,
resxGeneratedApplicationResourcesClass.GetTypeInfo().Assembly));
}
public override string GetString(string name, CultureInfo culture)
{
return _resourceLoader.GetString(name);
}
}
All that's then left to do is call this when the app starts for the first time:
WinRTResourceManager.InjectIntoResxGeneratedApplicationResourcesClass(typeof(AppResources));
After making these changes everything should work fine now.
Of course this is absolutely a hack but I have notified the Xamarin.Forms team of the issue and they are looking into it so hopefully it will be solved soon!