1. 从self.navigationController.viewControllers中拿出需要保留的View Controller放到一个数组中
2. 向数组中添加需要push的View Controller
3. 调用[self.navigationController setViewControllers:array animated:YES]
1. 从self.navigationController.viewControllers中拿出需要保留的View Controller放到一个数组中
2. 向数组中添加需要push的View Controller
3. 调用[self.navigationController setViewControllers:array animated:YES]