A storyboard "container view" is just a standard UIView
object. There is no special "container view" type. In fact, if you look at the view hierarchy, you can see that the "container view" is a standard UIView
:
To achieve this programmatically, you employ "view controller containment":
- Instantiate the child view controller by calling
instantiateViewController(withIdentifier:)
on the storyboard object.
- Call
addChild
in your parent view controller.
- Add the view controller's
view
to your view hierarchy with addSubview
(and also set the frame
or constraints as appropriate).
- Call the
didMove(toParent:)
method on the child view controller, passing the reference to the parent view controller.
See Implementing a Container View Controller in the View Controller Programming Guide and the "Implementing a Container View Controller" section of the UIViewController Class Reference.
For example, in Swift 4.2 it might look like:
override func viewDidLoad() {
super.viewDidLoad()
let controller = storyboard!.instantiateViewController(withIdentifier: "Second")
addChild(controller)
controller.view.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(controller.view)
NSLayoutConstraint.activate([
controller.view.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 10),
controller.view.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -10),
controller.view.topAnchor.constraint(equalTo: view.topAnchor, constant: 10),
controller.view.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -10)
])
controller.didMove(toParent: self)
}
Note, the above doesn't actually add a "container view" to the hierarchy. If you want to do that, you'd do something like:
override func viewDidLoad() {
super.viewDidLoad()
// add container
let containerView = UIView()
containerView.translatesAutoresizingMaskIntoConstraints = false
view.addSubview(containerView)
NSLayoutConstraint.activate([
containerView.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 10),
containerView.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -10),
containerView.topAnchor.constraint(equalTo: view.topAnchor, constant: 10),
containerView.bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -10),
])
// add child view controller view to container
let controller = storyboard!.instantiateViewController(withIdentifier: "Second")
addChild(controller)
controller.view.translatesAutoresizingMaskIntoConstraints = false
containerView.addSubview(controller.view)
NSLayoutConstraint.activate([
controller.view.leadingAnchor.constraint(equalTo: containerView.leadingAnchor),
controller.view.trailingAnchor.constraint(equalTo: containerView.trailingAnchor),
controller.view.topAnchor.constraint(equalTo: containerView.topAnchor),
controller.view.bottomAnchor.constraint(equalTo: containerView.bottomAnchor)
])
controller.didMove(toParent: self)
}
This latter pattern is extremely useful if ever transitioning between different child view controllers and you just want to make sure one child's view is in the same location and the previous child's view (i.e. all the unique constraints for the placement are dictated by the container view, rather than needing to rebuild these constraints each time). But if just performing simple view containment, the need for this separate container view is less compelling.
In the examples above, I’m setting translatesAutosizingMaskIntoConstraints
to false
defining the constraints myself. You obviously can leave translatesAutosizingMaskIntoConstraints
as true
and set both the frame
and the autosizingMask
for the views you add, if you’d prefer.
See previous revisions of this answer for Swift 3 and Swift 2 renditions.
ViewController
's life cycle. The embeddedViewController
's life cycle by Interface Builder is normal, but the one added programmatically hasviewDidAppear
, neitherviewWillAppear(_:)
norviewWillDisappear
. – BluesviewWillAppear
andviewWillDisappear
are called on the child view controller, just fine. If you have an example where they're not, you should clarify, or post your own question asking why they're not. – Cautery