Reload main view after modal dismiss - swift

Question

In my Xcode-App, a modal can be opened from every view. Every 'base' view is having a different purpose, some are showing a table, some are doing not. How can I achieve to reload the 'base' view whenever the modal is dismissed?
It seems to be especially tricky as the views have such different structures and purposes. I tried viewWillAppear, viewDidAppear and viewDidLoad, but none of them seem to do the trick.

Answer 1

You can setup a delegate pattern so that your modal view can notify when it will or did disappear.
First you need to create a protocol for your delegate:
protocol ModalViewControllerDelegate: class {
func modalControllerWillDisapear(_ modal: ModalViewController)
}
Then your modal should have a delegate property (that will in the end be the presenting controller) and trigger the modalControllerWillDisapear method when needed:
final class ModalViewController: UIViewController {
weak var delegate: ModalViewControllerDelegate?
override func viewWillDisappear(_ animated: Bool) {
super.viewWillDisappear(animated)
delegate?.modalControllerWillDisapear(self)
}
}
And all view controller that will present your modal controller must conform to that protocol and assign itself as a delegate of the modal when presenting:
final class SomeViewController: UIViewController {
private func presentModalController() {
let modal = ModalViewController()
modal.delegate = self
self.present(modal, animated: true)
}
}
extension SomeViewController: ModalViewControllerDelegate {
func modalControllerWillDisapear(_ modal: ModalViewController) {
// This is called when your modal will disappear. You can reload your data.
print("reload")
}
}
Note: If you are using segues to present your modal, you can assign the delegate property in the prepare(for:sender:) method instead of in a custom method.
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
switch (segue.identifier, segue.destination) {
// Check that the segue identifer matches and destination controller is a ModalViewController
case ("showModalSegue", let destination as ModalViewController):
destination.delegate = self
case _:
break
}
}