android - Zoomed in RecyclerView does not scroll all the way -

i have custom recyclerview zooms, when zoomed in, doesn't scroll through whole view. stops little short on each end. since recyclerview nested inside horizontalscrollview, not scroll left , right completely. how fix this?

zoomrecyclerview.java

public class zoomrecyclerview extends recyclerview { private scalegesturedetector scalegesturedetector; private static final string tag = zoomrecyclerview.class.getsimplename();  private float scalefactor = 1.f; private static final float minscale = 1.0f; private static final float maxscale = 3.0f;  public zoomrecyclerview(context context, attributeset attrs) {     super(context, attrs);     scalegesturedetector = new scalegesturedetector(getcontext(), new scalegesturedetector.onscalegesturelistener() {         @override         public boolean onscale(scalegesturedetector detector) {             scalefactor *= detector.getscalefactor();              //makes sure user not zoom in or out past amount             scalefactor = math.max(minscale, math.min(scalefactor, maxscale));              //refresh view , compute size of view in screen             invalidate();              return true;         }          @override         public boolean onscalebegin(scalegesturedetector detector) {             return true;         }          @override         public void onscaleend(scalegesturedetector detector) {          }     }); }  @override public boolean ontouchevent(motionevent event) {     super.ontouchevent(event);      if (event.getpointercount() > 1) {         //notify scalegesturedetector event has happened         scalegesturedetector.ontouchevent(event);     }      return true; }  @override protected void dispatchdraw(@nonnull canvas canvas) {     //scales display, centered on user touching display     canvas.scale(scalefactor, scalefactor, scalegesturedetector.getfocusx(), scalegesturedetector.getfocusy());      super.dispatchdraw(canvas); } }