google maps middle of a polyline (centroid?)

Question

I have a list of polylines, just like google maps does when I click on the polyline I want an infowindow to show up just where I clicked, and it works just fine with this fu

Answer 1

Might be a bit old as well, but why not add the infobox on the click?

infowindow.setPosition(event.latLng);
infowindow.open(this.getMap());

If it's a click that is.