why do serviceSubscriberCellularProviders return nil? (in iOS 12)

Question

Question about CTCarrier from CoreTelephony. I heard that I should use serviceSubscriberCellularProviders instead of subscriberCellularProvider in iOS 12 because subscriberCellu

Answer 1

It's a bug in iOS 12.0.x, and it has fixed in iOS 12.1

Answer 2

I think it's an Apple's bug. Try this:

    CTTelephonyNetworkInfo *networkStatus = [[CTTelephonyNetworkInfo alloc] init];
if (@available(iOS 12.0, *)) {
    NSDictionary *info = networkStatus.serviceSubscriberCellularProviders;
    NSLog(@"%@", [networkStatus valueForKey:@"serviceSubscriberCellularProvider"]);
}

It works well on iPhone XS Max (double Sim cards).And it seems to be a private method.