navigationbar+modifier.swift

extension View {
    func navigationBarColor(_ backgroundColor: UIColor?, textColor: UIColor?) -> some View {
        modifier(NavigationBarModifier(backgroundColor: backgroundColor, textColor: textColor))
    }
}

struct NavigationBarModifier: ViewModifier {
        
    var backgroundColor: UIColor?
    var textColor: UIColor?
    
    init( backgroundColor: UIColor?, textColor: UIColor?) {
        self.backgroundColor = backgroundColor
        UINavigationBar.appearance().largeTitleTextAttributes = [.foregroundColor: textColor ?? .black]
        UINavigationBar.appearance().titleTextAttributes = [.foregroundColor: textColor ?? .black]
    }
    
    func body(content: Content) -> some View {
        ZStack{
            content
            VStack {
                GeometryReader { geometry in
                    Color(self.backgroundColor ?? .clear)
                        .frame(height: geometry.safeAreaInsets.top)
                        .edgesIgnoringSafeArea(.top)
                    Spacer()
                }
            }
        }
    }
}