ZCYTabBarController * tabBarController = (ZCYTabBarController *)self.window.rootViewController;

// 取到navigationcontroller

RTRootNavigationController * nav = (RTRootNavigationController *)tabBarController.selectedViewController;

//取到nav控制器当前显示的控制器

UIViewController * baseVC = (UIViewController *)nav.visibleViewController;

// 否则，跳转到我的消息

JCHATConversationListViewController * helpOrder = [JCHATConversationListViewController new];

[baseVC.navigationController pushViewController:helpOrder animated:YES];