Send SMS to Selected Contacts in iPhone

Question

I want to send SMS invite to multiple phone numbers selected from the contact list, I tried to use ABPeoplePicker but it is not coming correctly, my contact list is always showing blank.

- (void)viewDidLoad
{
  [super viewDidLoad];

   UIBarButtonItem *addButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(showAddressBook)];

   self.navigationItem.rightBarButtonItem = addButton;
}

#pragma mark - Private method implementation

-(void)showAddressBook{
    _addressBookController = [[ABPeoplePickerNavigationController alloc] init];
   [_addressBookController setPeoplePickerDelegate:self];
   [self presentViewController:_addressBookController animated:YES completion:nil];
}

I feel I am doing something wrong, can anyone help me.