javascript - backbone.paginator - update per page -

i'm using backbone.paginator in project. have dropdown allows users select results per page. have figure out how make work :-)

so far if this:

this.collection.goto(page, {     data: {per_page: newresultsperpage} }); 

where newresultsperpage number of results user has selected dropdown. correct number of results come server, backbone.paginator doesn't correctly update number of pages. there method can call update / reset backbone.paginator plugin?

it looks there howmanyper method missed in documentation. i'll leave question else searching similar issue in future.