如何使用Highcharts灰色主题？

Question

过去，我使用Highcharts灰色主题制作背景为深色背景和浅色的图形。我需要做的只是包括灰色主题脚本：

UITabBarController *tabBarController = (UITabBarController *)self.window.rootViewController;
tabBarController.selectedIndex = 1;
UITabBar *tabBar = tabBarController.tabBar;
UITabBarItem *tabBarItem1 = [tabBar.items objectAtIndex:0];
UITabBarItem *tabBarItem2 = [tabBar.items objectAtIndex:1];
UITabBarItem *tabBarItem3 = [tabBar.items objectAtIndex:3];
UITabBarItem *tabBarItem4 = [tabBar.items objectAtIndex:4];
tabBarItem1.title = @"Tab1"; tabBarItem2.title = @"Tab2";
tabBarItem3.title = @"Tab3"; tabBarItem4.title = @"Tab4";
[[UITabBarItem appearance] setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys: [UIColor whiteColor], NSForegroundColorAttributeName, nil] forState:UIControlStateNormal];
UIColor *titleHighlightedColor = [UIColor colorWithRed:153/255.0 green:192/255.0 blue:48/255.0 alpha:1.0];
[[UITabBarItem appearance] setTitleTextAttributes:[NSDictionary dictionaryWithObjectsAndKeys: titleHighlightedColor, NSForegroundColorAttributeName, nil] forState:UIControlStateHighlighted]; return YES;

包含此脚本不再更改图表主题。现在怎么样？