I am trying to change UITabBar background color runtime as theme changed. It is already working in iOS 17 as I am updating UITabBar.appearance().barTintColor and tintColor But for iOS first i need to change because I don't want that new elevated tabbar so I create custom tabbar controller as described in https://stackoverflow.com/questions/78631030/how-to-disable-the-new-uitabbarcontroller-view-style-in-ipados-18 Accepted Answer by awulf. And by doing this, My tabbar looks same like Old and it is working in iPhone and ipad for iOS 16, iOS 17 and iOS 18 too. But the issue is that I am unable to change my tabbar background color. I have also checked this forum: https://forums.developer.apple.com/forums/thread/761056 But not able to change I have set below 3 properties but no effect let appearance = UITabBar.appearance() appearance.backgroundColor = appearance.barTintColor = appearance.tintColor = I have created CustomTabBarController in storyboard and all working fine Also the appearance changed only once per application lifecycle. It will change color by restarting the app then it will pick last selected theme and the colors are changed. but not able to change colors runtime I have also did below code for reloading purpose tabBar.setNeedsLayout() tabBar.setNeedsDisplay() But nothing work