pointsCanvas(canvas);
if (pointList.size() > 0) {
   Point a = pointList.get(0);
   for (int i = 0; i < pointList.size(); i++) {
       Point b = pointList.get(i);
       LineCanvas(canvas,a,b);
       a = b;
   }
   if (movingNoPoint) {
       LineCanvas(canvas,a,new Point(movingX,movingY));
   }