1、修改导航栏字体颜色
self.title = @"title";
[self.navigationController.navigationBar setTitleTextAttributes:
@{NSFontAttributeName:[UIFont systemFontOfSize:12],
NSForegroundColorAttributeName:[UIColor redColor]}];
2、修改导航栏背景颜色颜色
self.navigationController.navigationBar.barTintColor = [UIColor whiteColor];
