I need to extend my contentView in DM-5.5 to include an extra column. How much code do I need to duplicate in my extension, to make it do what I want it to do, as well as what it already does?

For example, if I want everything to be the same, but want to add one column to the resulted display, whether the result of just browsing the sections, workspaces or seeing search results, do I need to completely rewrite the code for contentViews or can I just include an xml fragment that defines the widget and document_virtual_navigation_listing_ajax layout and all views can pull that widget into use?

If I can figure out how to clarify my question, I will edit this post.