Question

I used the codes below to notify the menu selection index

    NSDictionary *userInfo=  [NSDictionary dictionaryWithObject:[NSString stringWithFormat:@"123"] 
                                              forKey:@"Index"];
   [[NSNotificationCenter defaultCenter] postNotificationName: @"notifyToMenuSelectionNotification"
                                                    object: userInfo];



-(void)menuSelectionNotification:(NSNotification *)notification
{
  NSLog(@"%@", notification.userInfo);


}

menuSelectionNotification is triggered correctly,

but NSLog output notification.userInfo is still {null}

Welcome any comment1

Answer 1

you are passing object in wrong way. Please try this –

NSDictionary *userInfo=  [NSDictionary dictionaryWithObject:[NSString stringWithFormat:@"123"] 
                                              forKey:@"Index"];

[[NSNotificationCenter defaultCenter] postNotificationName:@"notifyToMenuSelectionNotification"
                                      object:nil
                                      userInfo:userInfo];