Swift3.0 tabbar背景色，文字颜色修改

self.tabBar.tintColor=UIColor.orange

self.tabBar.barTintColor=UIColor.red

UITabBarItem.appearance().setTitleTextAttributes(

[NSForegroundColorAttributeName:UIColor.gray], for:.normal)

UITabBarItem.appearance().setTitleTextAttributes(

[NSForegroundColorAttributeName:UIColor.gray], for:.selected)