iOS改变NavigationBar和TabBar相关颜色

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
    UIColor * mainColor = [UIColor colorWithRed:61 / 255.0f green:189 / 255.0f blue:119 / 255.0f alpha:1.0f];
    //单例获取NavigationBar
    UINavigationBar * navigationBar = [UINavigationBar appearance];
    //改变背景颜色
    [navigationBar setBarTintColor:mainColor];
    //改变标题颜色
    [navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName:[UIColor whiteColor]}];
    //改变Item颜色
    [navigationBar setTintColor:[UIColor whiteColor]];
    //设置tab被选中的颜色
    UITabBar * tabBar = [UITabBar appearance];
    [tabBar setTintColor:mainColor];
    
    return YES;
}