registerUserNotificationSettings不显示警报

Question

I'm asking the user for permission to use local notifications on iOS 8 like this:

    if ([UIApplication instancesRespondToSelector:@selector(registerUserNotificationSettings:)]){
    UIUserNotificationType types = UIUserNotificationTypeBadge |
    UIUserNotificationTypeSound | UIUserNotificationTypeAlert;
    UIUserNotificationSettings *notificationSettings =
    [UIUserNotificationSettings settingsForTypes:types categories:nil];
    [[UIApplication sharedApplication] registerUserNotificationSettings:notificationSettings];
}

And I'm handling like this in my AppDelegate:

-(void)application:(UIApplication *)application didRegisterUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings {
[[NSNotificationCenter defaultCenter] postNotificationName:@"didRegisterUserNotificationSettings" object:nil];
}

But no alert is shown? It skips right to the delegate callback. Why is this? I'm doing this in the iOS simulator.

Thanks!

Answer 1

警报仅显示一次，要在模拟器上再次显示，请按iOS Simulator -> Reset Contents and Settings