Triangle triangle = triangleShape.getGraphicsAlgorithm; EList<Point> trianglePoints = triangle.getPoints(); trianglePoints.get(0).setX(1); trianglePoints.get(0).setY(1); trianglePoints.get(1).setX(2); trianglePoints.get(1).setY(2); trianglePoints.get(2).setX(3); trianglePoints.get(2).setY(3);