Getting IClassifier to work with custom content type

Question

I am trying to add syntax highlighting for a custom content type based on text e.g.

static class RTextContentType
{
    public const string ContentTypeName = Constants.CONTENT_TYPE;
    [Export, Name(ContentTypeName), BaseDefinition("text")]
    internal static ContentTypeDefinition ContentTypeDefinition = null; // set via MEF
}

Then the classifier provider is declared like this,

[Export(typeof(IClassifierProvider)), ContentType(Constants.CONTENT_TYPE)]
class RTextClassifierProvider : IClassifierProvider
{
   ...
}

The problem is, that the constructor of the provider is never get called for my specified extensions. Note here, that I provide the editor factories and the file extensions are associated with the factory. I can see the factory getting initialized through debugging for all associated files.

If I change the content type to "text" the constructor gets called.

So the question is, how can one map a custom content type to a file extension ?

Second note, using FileExtensionToContentTypeDefintion

is not an option, as this does not allow a lot of features..

Thanks for the help :)

Oregon

Answer 1

Your implementation of IVsEditorFactory is responsible for setting the content type of the text displayed in the editor. The default implementation of this interface includes special support for FileExtensionToContentTypeDefinitionAttribute as a simple extension mechanism for users that don't require some of the more advanced features (e.g. projection buffers for multiple content types).

The DjangoEditorFactory class includes a nested class named TextBufferEventListener, which shows one example for how an editor factory might assign the content types to the buffers displayed in an editor window.

Overawe

Yes, I am looking at this implementation right now. Seems rather complicated. So I guess I will also have to implement an instance of this, but probably without the elision buffer. What do you mean by default implementation btw ? The template from Visual Studio ? I am not planning on having multiple content types, so maybe this default implementation could be helpful. – Oregon

If you do not associate your file extension with a custom editor factory, then Visual Studio will use its own internal implementation of the editor factory. That implementation assigns content types through a number of different ways, one of which is the attribute you mentioned. – Overawe

But of course, using the default implementation doesn't allow man to create navigation bars etc. or adding new file extensions to the editor.. – Oregon

@Oregon You are correct about user-defined file extensions, but not about the navigation bars. However, the navigation bars cannot be added by MEF so you'll need to use a VSPackage for it. – Overawe

I did manage to add navigation bars, but then there were conflicts between my plugin and power productivity tools. Ctrl+Clicking on a token of my extension give the error "No symbol references are found". All this happened after I added the LanguageService - so now I am trying to go the "right" way.. :) I mean I have a tokenizer,parser and everything. I just need to get them triggered.. – Oregon

I found why my plugin was not working with power productivy tools : visualstudiogallery.msdn.microsoft.com/… Everything work perfect now :) – Oregon