Objective-C: whose view is not in the window hierarchy - ios

Question

I have this code that works so that once i press a button the view changes in my storyboard:
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
ViewController *viewController = (ViewController *)[storyboard instantiateViewControllerWithIdentifier:#"view1"];
[self presentViewController:viewController animated:YES completion:nil];
This code work but when i use it again to change back to my original view using:
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard" bundle:nil];
ViewController *viewController = (ViewController *)[storyboard instantiateViewControllerWithIdentifier:#"view2"];
[self presentViewController:viewController animated:YES completion:nil];
It does not work and i receive this error:
Warning: Attempt to present <UIViewController: 0x863ad30> on <UITabBarController: 0x86309b0> whose view is not in the window hierarchy!
The identifies are set and i am not the functions in my viewdidload so i do not know how to fix this.
Can anybody help?

Answer 1

Try this,
First Method
-(IBAction)signin:(id)sender
{
UIStoryboard *sb = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
UIViewController *vc = [sb instantiateViewControllerWithIdentifier:#"viewController"];
[[[[UIApplication sharedApplication] delegate] window] setRootViewController:vc];
}
Second method (to return back to the previous view)
- (IBAction)signout:(id)sender
{
UIStoryboard *sb = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
UIViewController *vc = [sb instantiateViewControllerWithIdentifier:#"parentViewController"];
[[[[UIApplication sharedApplication] delegate] window] setRootViewController:vc];
}

Answer 2

This might happen if you call the method before calling makeKeyAndVisible, so move the calling after that.
If not try the hack below:
[[[[[UIApplication sharedApplication] delegate] window] rootViewController] presentViewController:viewController animated:YES completion:nil];

Answer 3

The error message says all: you have to add the view controller's view to the window before presenting the view controller:
UIWindow* keyWindow= [[UIApplication sharedApplication] keyWindow];
[keyWindow addSubview: viewController.view];
[self presentViewController:viewController animated:YES completion:nil];