To create a view controller:
UIViewController * vc = [[UIViewController alloc] init];
To call a view controller (must be called from within another viewcontroller):
[self presentViewController:vc animated:YES completion:nil];
For one, use nil rather than null.
Loading a view controller from the storyboard:
NSString * storyboardName = @"MainStoryboard"; UIStoryboard *storyboard = [UIStoryboard storyboardWithName:storyboardName bundle: nil]; UIViewController * vc = [storyboard instantiateViewControllerWithIdentifier:@"IDENTIFIER_OF_YOUR_VIEWCONTROLLER"]; [self presentViewController:vc animated:YES completion:nil];
Identifier of your view controller is either equal to the class name of your view controller, or a Storyboard ID that you can assign in the identity inspector of your storyboard.