UITextInputCurrentInputModeDidChangeNotification return nill in ios 8.3

I want to detect current input mode of keyboard, and change text direction with respect to it (rtl if arabic, and ltr if english) in viewDidLoad:

- (void)viewDidLoad {
[super viewDidLoad];

[[NSNotificationCenter defaultCenter] addObserver:self
                                         selector:@selector(changeInputMode:)
                                             name:UITextInputCurrentInputModeDidChangeNotification object:nil];

} and in changeInputMode:

-(void)changeInputMode:(NSNotification *)notification
{
    UITextInputMode *thisInputMode = [notification object];

    NSLog(@"inputMethod=%@",thisInputMode);
}

but thisInputMode is nill! if I use this code instead:

    NSString *inputMethod = [[UITextInputMode currentInputMode] primaryLanguage];
    NSLog(@"inputMethod=%@",inputMethod);

it works fine and detects current password, but currentInputMode is deprecated. why [notification object] returns nill?