我的已知数据是我的当前位置(GeoPoint)和以米为单位的半径。我想根据map投影和半径在当前位置周围画圈。我的mapView叠加层确实覆盖了绘图方法，例如@Overridepublicvoiddraw(Canvascanvas,MapViewmapView,booleanshadow){Projectionprojection=mapView.getProjection();GeoPointmyLocationGeoPoint=getLocationGeoPointFromSomeSource();PointmyPoint=newPoint();projection.toPixel