Android: is there a way to apply a right-margin span within an edittext?

I'm looking for something similar to LeadingMarginSpan, but capable of applying both left- and right- margins to the text, as opposed to just a left margin.

What I'm trying to do is have the option of making some paragraphs narrower than others within the same edittext, so it might looks something like this:

blah blah blah blah blah blah blah blah
blah blah blah blah blah blah blah blah
blah blah

     blah blah blah blah blah blah
     blah blah blah blah blah blah
     blah blah blah blah blah blah
     blah

blah blah blah blah blah blah blah blah
blah blah blah blah blah blah blah blah
blah blah blah blah blah

As far as I know there are no pre-defined spans that do this, and I don't know how to go about creating a new span from scratch that could do it. Any help would be greatly appreciated!