android - ImageView Is Not Touchable in a View Class When tried to draw on it -

imageview not touchable in view class when tried draw on ... problem when try draw on imageview m not able draw on ... tried lot .. not able ..... declared iv.setontouchlistener(this); still not touchable .. appreciated , thanks!

public class brushview extends view implements ontouchlistener {         private paint brush = new paint();         private path path = new path();         public layoutparams params;         imageview iv;          public brushview(context context) {             super(context);             brush.setantialias(true);             brush.setcolor(color.blue);             brush.setstyle(paint.style.stroke);             brush.setstrokejoin(paint.join.round);             brush.setstrokewidth(15f);             iv = new imageview(context);             iv.setontouchlistener(this);             iv.setbackgroundresource(r.drawable.ic_launcher);             params = new layoutparams(layoutparams.match_parent,                     layoutparams.match_parent);             iv.setlayoutparams(params);          }          @override         protected void ondraw(canvas canvas) {             canvas.drawpath(path, brush);         }          @override         public boolean ontouch(view v, motionevent event) {             float pointx = event.getx();             float pointy = event.gety();              // checks event occurs             switch (event.getaction()) {             case motionevent.action_down:                 path.moveto(pointx, pointy);                  return true;             case motionevent.action_move:                 path.lineto(pointx, pointy);                 break;             case motionevent.action_up:                 break;             default:                 return false;             }             // force view draw.             postinvalidate();             return false;          }     }