OC 一张图片填充满整个导航栏(包含X系列)

    ///UIBarMetricsCompact 整个充满导航栏
    UIImage *backGroundImage = [UIImage imageNamed:@"vip_nav_bg"];
    backGroundImage = [backGroundImage resizableImageWithCapInsets:UIEdgeInsetsZero resizingMode:UIImageResizingModeStretch];
    [self.navigationController.navigationBar setBackgroundImage:backGroundImage forBarMetrics:UIBarMetricsDefault];
    ///不加下面， 会出现导航栏偏移
    [self.navigationController.navigationBar setTranslucent: YES];