why i can not run GPS?

Discussion created by liushub-esrichina-com-cn-esridist on Sep 8, 2010
Latest reply on Sep 8, 2010 by kduarte
I copy the code from the Forums,but it still can run, when i get the GPS's current point's x,y , it always display 0. Could some one help me?
[self.mapView.gps start];
self.mapView.gps.autoPan = YES;