ArcGis旋转map上的图标

Drawable drawable = getResources().getDrawable(R.drawable.arrow);
					PictureMarkerSymbol arrow_symbol = new PictureMarkerSymbol(drawable);
					arrow_symbol.setAngle(x);   //角度
					Point  loc= new Point(1.4191862462692365E7,5183685.4328131145); //获取的定位
					Graphic gArrow = new Graphic(loc, arrow_symbol);
					graphicsLayer.updateGraphic(1, gArrow);