How can I programmatically present a view controller modally? - ios

Question

Edit: When solving this problem, I found that it is much easier to start with your UITabBarController, then perform login validation via your AppDelegate.m's didFinishLaunchingWithOptions: method.
Question:
This code is in the the application didFinishLaunchingWithOptions: method in my AppDelegate.m
if([result isEqualToString: #"log"])
{
UIStoryboard *storyboard = [UIStoryboard storyboardWithName:#"Main" bundle:nil];
UIViewController *ivc = [storyboard instantiateViewControllerWithIdentifier:#"TabBarControl"];
[(UINavigationController*)self.window.rootViewController pushViewController:ivc animated:NO];
NSLog(#"It's hitting log");
}
It simply takes an HTTP response for the user being logged in, and takes them to my TabBarController. The problem is that it's using a push rather than a modal transition to display the page. Since presentModalViewController method is deprecated or deleted in iOS7, how can I programmatically force a modal presentation?
EDIT:
)

Answer 1

Swift
This is how you would do it in Swift without referencing the navigation controller:
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let secondViewController = storyboard.instantiateViewController(withIdentifier: "secondViewController") as! SecondViewController
self.present(secondViewController, animated: true, completion: nil)
Change the storyboard name, view controller, and id as needed.
See also how to dismiss a view controller programmatically.

Answer 2

In swift 4.2 you can do it like this. For those who want this answer in swift updated version.
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let controller = storyboard.instantiateViewController(withIdentifier: "ExampleViewController")
self.present(controller, animated: true, completion: nil)

Answer 3

In Swift 3/4
let storyB = UIStoryboard(name: "Main", bundle: nil)
let secondViewController = storyB.instantiateViewController(withIdentifier: "SecondViewControllerID") as! SecondViewController
self.present(secondViewController, animated: true, completion: nil)

Answer 4

let storyB = UIStoryboard(name: "Main", bundle: nil)
let secondViewController =
storyB.instantiateViewController(withIdentifier:
"SecondViewControllerID") as! SecondViewController
self.present(secondViewController, animated: true, completion: nil)
In the secondViewController use this code to go back.
self.dismiss(animated: true, completion: nil)