iOS 15 适配
1.滑动导航栏变白
2.滑动tabBar背景色变化
3.tabItem文字颜色不会改变，默认系统蓝色
4.UITableView 顶部多出空白

对更新到iOS15后，出现的问题，可以分别做以下设置进行适配：
1.对UINavigationBar做如下设置

if #available(iOS 15.0, *) {
            let appearnce = UINavigationBarAppearance()
            appearnce.configureWithOpaqueBackground()
            appearnce.backgroundColor = HEX_ThemeBlack
            appearnce.titleTextAttributes = [<#NSAttributedString#>,<#NSAttributedString#>]
            navigationBar.standardAppearance = appearnce
            navigationBar.scrollEdgeAppearance = appearnce
}

2.对UITabBar做如下设置

if #available(iOS 15.0, *) {
            let appearnce = UITabBarAppearance()
            appearnce.configureWithOpaqueBackground()
            appearnce.backgroundColor = HEX_ThemeBlack
            tabBarController.tabBar.standardAppearance = appearnce
            tabBarController.tabBar.scrollEdgeAppearance = appearnce
 }

3.对UITabBarItem做如下设置

if #available(iOS 15.0, *) {
            let appearnce = UITabBarAppearance()
            let itemAppearance = UITabBarItemAppearance()
            itemAppearance.normal.titleTextAttributes = <#Dictionary<NSAttributeString.Key,Any>#>
             itemAppearance.selected.titleTextAttributes = <#Dictionary<NSAttributeString.Key,Any>#>
            appearnce.stackedLayoutAppearance = itemAppearance
            appearnce.configureWithOpaqueBackground()
            appearnce.backgroundColor = HEX_ThemeBlack
            tabBarController.tabBar.standardAppearance = appearnce
            tabBarController.tabBar.scrollEdgeAppearance = appearnce
 }

4.对UITableView的设置
可以在基类的初始化方法中添加，也可以使用methodSwizzle去替换方法中添加

if #available(iOS 15.0, *) {
            self.sectionHeaderTopPadding = 0
}