swift 5 UITabBar的文字颜色设置

第一种当时，拿到UITabBarItem的appearance 前景色
UITabBarItem.appearance().setTitleTextAttributes([NSAttributedString.Key.font:UIFont.systemFont(ofSize: 26)], for: .normal)

    UITabBarItem.appearance().setTitleTextAttributes([NSAttributedString.Key.font:UIFont.systemFont(ofSize: 26)], for: .selected)
    
    self.tabBar.backgroundColor = UIColor.systemGray5
    tabBar.barTintColor = UIColor.black

直接设置。
第二种方式在
添加每一个ChildVc，拿到

tabBarItem?.setTitleTextAttributes([NSAttributedString.Key.foregroundColor : UIColor.gray,
                                                NSAttributedString.Key.font : UIFont.systemFont(ofSize: 18)],
                                               for: .normal)
            tabBarItem?.setTitleTextAttributes([NSAttributedString.Key.foregroundColor : UIColor.black,
                                                NSAttributedString.Key.font : UIFont.systemFont(ofSize: 18)],
                                               for: .selected)

            tabBarItem?.titlePositionAdjustment = UIOffset(horizontal: 0, vertical: -15)
       
            tabBarItem?.imageInsets = UIEdgeInsets(top: 5.5, left: 0, bottom: -5.5, right: 0)