How do I customize Word 2010 ribbon only on demand in a VSTO4 add-in?

I am currently diving into VSTO add-in development and ribbon customization for Word 2010. This works fine, but has a drawback: The ribbon customization should take place for only certain documents, but the IRibbonExtensi开发者_如何学运维bility.GetCustomUI() method is obviously called on application startup before any document is loaded. How can I accomplish this requirement?

You're right that it's only called once. About your only choice (and what's worked for me reasonably well), is to define EVERYTHING in your ribbon up front, then set the VISIBLE property to false or true as applicable depending on what doc is loaded, or whatever else is happening in your addin.

@drventure is right, you have to define your ribbon up front, then show/hide different buttons on the ribbon.

What might help you though is some of the features in a project I have been working on, VSTO Contrib, it allows you to create a ViewModel, which will be created for each open document, and it will discover and wire up the ribbon xml by convention.

In your case this would mean you can bind the ribbon buttons visibility to a property on the viewmodel, and you don't have to worry about keeping the window/documents syncronised. Have a read of http://jake.ginnivan.net/vsto-contrib/ribbon-factory and see if it will help you solve your problem with a heap less code =)