Switching containerView content from within viewController - ios

Question

I have three viewControllers Main, A, B. Main ViewController holds ContainerView and other content as well does all transactions in containerView. ViewControllerA has ButtonA when pressing it content of container has to change to ViewControllerB
how can I do that? I cannot find any similar examples.

Answer 1

You will need to create create delegate for that.
First create a protocol
protocol ViewControllerADelagate {
func didPressOnButtonA()
}
In ViewControllerA add following delegate variable
class ViewControllerA {
....
var delegate : ViewControllerADelagate?
....
}
In ViewControllerA add following on button press
#IBAction buttonAPressed(sender : UIButton) {
self.delegate?.didPressOnButtonA()
}
In MainViewController assign the delegate of ViewControllerA to self
like
vcA.delegate = self
Implement the delegate method in MainViewController like
func didPressOnButtonA {
let storyboard : UIStoryboard = UIStoryboard(name: storyboard, bundle: nil)
let vcB : UIViewController = storyboard.instantiateViewController(withIdentifier: viewControllerIdentifier) as! ViewControllerB
self.addChildViewController(vcB)
self.containerView.addSubview(vcB.view)
vcB.didMove(toParentViewController: self)
vcB.view.frame = CGRect.init(x: 0, y: 0, width: self.containerView.frame.size.width, height: self.containerView.frame.size.height)
}

Answer 2

While click on ButtonA. Post a notification to mainView. There remove viewController A from Container and add View Controller B .

Answer 3

I have created a storybaord with sample. you can download it from here.
You need to change the embed view to a navigation controller and then you can use segue to show second view on button press. also hide/show navigation bar depends on requirement.

Answer 4

I am not fond of using these but you can get the child view controller from parent controller by accessing an array childViewControllers. On view did load you would need to go through all of these and find the one that can be typecast into your view controller type like
childViewControllers.flatMap { $0 as? AViewController }.first.
Now that you found the correct view controller I suggest you to either assign yourself as a delegate
childViewControllers.flatMap { $0 as? AViewController }.first.delegate = self
or simply add a button target
childViewControllers.flatMap { $0 as? AViewController }.first.button.addTarget...
Now this can easily be done if you simply embed the 2 view controllers at the same time (have 2 content views) and hide one or the other depending on which you show. At least this way you can assign connection straight away. When this is not the case then you will need to iterate again when setting a new controller or assign connections where you initialize a new view controller.
In this case it then seems better to turn the system around: When child view controller is loaded rather call
self.delegate = parentViewController as? AViewControllerDelegate
Although this will work it seems wrong that a child view controller will control who its listener is so I advise you to avoid such coding.
I in general use a custom implementation for container view which you could do the same or maybe at least subclass the native one and target the methods so that your code will look something like:
private onBPressed() {
containerView.setViewController(viewController: BViewController(delegate: self), animation: .fade)
}

Answer 5

When you pressing Button A from View A:
#IBAction func BtnAPress(_ sender: Any)
{
//Moving Storyboard
let Storyboard = UIStoryboard(name: "Main", bundle: nil)
let MainVC : UIViewController = Storyboard.instantiateViewController(withIdentifier: "ViewControllerB")
self.present(MainVC, animated: true, completion: nil)
}