How to push a view in iOS8 and Swift - swift

Question

I am updating an app that pre-dates iOS5 - consequently much needs to change.
In the existing app we push a view (created in a nib) onto a screen that contains a UIPickerView/UIDatePicker to allow the user to make selections.
I this should be an easy thing to migrate to iOS8/Swift but I have spent the past 24h trying to work out the best way to do this with Storyboard/Segue, Container views, viewControllers, UIPopoverPresentationControler etc. with little consensus (even apple's sample code pushes the UIDatePicker in a table cell)
This seems to be a common requirement and I would appreciate any advice/comments on how others have solved this.
Many thanks

Answer 1

Try this
self.performSegueWithIdentifier("your segue identifier", sender: self)

Answer 2

Thanks for the answers and questions seeking clarification.
After a weekend of investigation I realize that I have been stuck in an old iOS paradigm.
With iOS8 everything has moved to ViewController presentation, allowing the developer to control the animation and define behavior on a range of devices (in different orientations).
The definitive answer to my question (I believe) is as follows:
Use UIPresentationController to present the desired UIViewController:
The view controller is the view to display (use code, nib or storyboard to create the picker view)
The presentation controller manages how it is presented (e.g. size, presentationStyle)
This is also the place to handled transparent/blurred views to cover existing content
check out:
func sizeForChildContentContainer(container: UIContentContainer, withParentContainerSize parentSize: CGSize) -> CGSize
func frameOfPresentedViewInContainerView() -> CGRect
The UIPresentationController needs a transitioning delegate to manage the presentation (conforms to UIViewControllerTransitioningDelegate)
{
// We need to create a presentation controller to manage the presentation of VC
func presentationControllerForPresentedViewController(presented: UIViewController, presentingViewController presenting: UIViewController!, sourceViewController source: UIViewController) -> UIPresentationController? {
let opc = OverlayPresentationController(presentedViewController: presented, presentingViewController: source)
return opc
}
// Get hold of an animation controller for presentation
func animationControllerForPresentedController(presented: UIViewController, presentingController presenting: UIViewController, sourceController source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
let animationController = OverlayAnimatedTransitioning()
return animationController
}
// Get hold of an animation controller for dismissal
func animationControllerForDismissedController(dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
let animationController = OverlayAnimatedTransitioning()
return animationController
}
which in turn requires an animation controller (UIViewControllerAnimatedTransitioning) to handle the animation (slide, dissolve or something more adventurous):
func transitionDuration(transitionContext: UIViewControllerContextTransitioning) -> NSTimeInterval {
return 0.5
}
func animateTransition(transitionContext: UIViewControllerContextTransitioning) {
let fromViewController = transitionContext.viewControllerForKey(UITransitionContextFromViewControllerKey)!
let toViewController = transitionContext.viewControllerForKey(UITransitionContextToViewControllerKey)!
let containerView = transitionContext.containerView()
let animationDuration = self .transitionDuration(transitionContext)
containerView.addSubview(toViewController.view)
UIView.animateWithDuration(animationDuration, animations: { () -> Void in
<<< Animation Here>>>)
}) { (finished: Bool) in
transitionContext.completeTransition(true)
}
With the building blocks in place, the desired UIViewController may then be called (using an action/selector/segue) and by setting the transitioningDelegate property of the desired view the desired effect will be invoked:
#IBAction func showOVC(sender: AnyObject) {
let ovc = OverlayViewController()
let overlayTransitioningDelegate = OverlayTransitioningDelegate()
ovc.transitioningDelegate = overlayTransitioningDelegate
self.presentViewController(ovc, animated: true, completion: nil)
}
Dismissal is handled in the same way, simply by calling:
dismissViewControllerAnimated(true, completion: nil)
More information can be obtained via the docs and the excellent WWDC video which made everything clear for me: A look inside presentation controllers
or see apple's example code: LookInside
Bottom line - not as simple as before (assuming a single device in one orientation), but for a little more complexity there is far greater control of views and animation, with the ability to scale to multiple devices.
I hope that this helps people in a similar position
Thanks