导航栏背景和文字设置
导航栏 背景和title颜色
背景色
self.navigationController.navigationBar.barTintColor = [UIColor colorWithHex:@"#FFFEFE"];//[UIColor whiteColor];
title颜色(想显示啥样就啥样)
[self.navigationController.navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor colorWithHex:@"#db2533"]}];