[self.navigationController.navigationBar setTitleTextAttributes:
@{NSFontAttributeName:[UIFont systemFontOfSize:19],
NSForegroundColorAttributeName:[UIColor whiteColor]}];
[self.navigationController.navigationBar setTitleTextAttributes:
@{NSFontAttributeName:[UIFont systemFontOfSize:19],
NSForegroundColorAttributeName:[UIColor whiteColor]}];