我如何检查真假,因为这不是
BOOL *isLoggedIn = [[NSUserDefaults standardUserDefaults] boolForKey:kSignedInBool];
BOOL *userSignedUp = [[NSUserDefaults standardUserDefaults] boolForKey:kHasUserEverSignedUpBool];
if(userSignedUp == NO || isLoggedIn == NO) { // they don't have an account so can't sign in.
//Show the modal opening screen path
[self performSegueWithIdentifier:@"showOpeningScreen" sender:self];
} else { //
// We have signed up before so findNearbyamulanes
[self performSelector:@selector(findNearByAmbulances) withObject:nil afterDelay:4.0];
}