方法一
入栈
UIChildDemoViewController *childView = [[UIChildDemoViewController alloc] init];
[self.navigationController pushViewController:childView animated:YES];
出栈
[self.navigationControllerpopToRootViewControllerAnimated:YES];
方法二
入栈
UIChildDemoViewController *childView = [[UIChildDemoViewController alloc] init];
[self.navigationController pushViewController:childView animated:YES];
出栈
[self.navigationController presentModalViewController:childView animated:YES];