UINavigationController从父级转换为孙级

Question

我需要在UINavigationController层次结构中从父视图控制器转换到孙视图控制器。我怎样才能做到这一点？我试过这些......

NSMutableArray *vcs = [[self.navigationController viewControllers] mutableCopy];

// menuvc is next 
NOZMenuTVController *menuvc = [self.storyboard instantiateViewControllerWithIdentifier:@"menuViewController"];
[vcs addObject:menuvc];

// payvc comes after menu vc as in a master detail relationship 
NOZPaymentViewController *payvc = [self.storyboard instantiateViewControllerWithIdentifier:@"paymentViewController"];
[vcs addObject:payvc];

// This causes a crash
[self.navigationController setViewControllers:vcs animated:YES];

这首先起作用，但当我回来再试一次时会导致崩溃

NOZMenuTVController *menuvc = [self.storyboard instantiateViewControllerWithIdentifier:@"menuViewController"];
[self.navigationController pushViewController:menuvc animated:NO];

NOZPaymentViewController *payvc = [self.storyboard instantiateViewControllerWithIdentifier:@"paymentViewController"];
[self.navigationController pushViewController:payvc animated:YES];

Answer 1

第二种解决方案有效。它没有提前工作，因为在子控制器的某个地方，我正在设置UINavigationController的委托（在dealloc期间将navctrl的委托设置为nil没有帮助），当用户回来时，导航控制器本身就不再存在了。