Views from storyboards won't appear in Xcode Preview - ios

I try to use Xcode Preview feature. It works well when I add views directly in code, but if I add any views via storyboard, preview won't show these views. Here is my code:
import UIKit
final class ViewController: UIViewController {
#IBOutlet weak var segmentedControl: UISegmentedControl?
}
#if canImport(SwiftUI) && DEBUG
import SwiftUI
struct ViewControllerRepresentable: UIViewRepresentable {
func makeUIView(context: Context) -> UIView {
return ViewController().view
}
func updateUIView(_ view: UIView, context: Context) {
}
}
#available(iOS 13.0, *)
struct ViewController_Preview: PreviewProvider {
static var previews: some View {
Group {
ViewControllerRepresentable()
}
}
}
#endif
That's my controller in simulator and storyboard:
That's how this controller looks in preview:

Set storyboardID (for example "ViewController") for your ViewController in storyboard.
Then create viewController from storyboard
func makeUIView(context: Context) -> UIView {
let viewController = UIStoryboard(name: "Main", bundle: nil)
.instantiateViewController(withIdentifier: "ViewController")
return viewController.view
}
Use your storyboard name instead of "Main" if it's different.

Related

How can I navigate to Storyboard VC from SwiftUI View?

I created this SwiftUI View:
import SwiftUI
struct ContentView: View {
var body: some View {
NavigationView{
MasterView()
}.navigationViewStyle(DoubleColumnNavigationViewStyle())
}
}
struct MasterView: View {
var body: some View {
Form {
Section(header: Text("Geplant")) {
Section {
NavigationLink(destination: /* How can I navigate to a Storyboard ViewController?*/) { Text("Berlin") }
}
}
}
.navigationBarTitle("Wähle Reise")
}
}
As you can read, I want to navigate at line "NavigationLink(destination: .....) to a Storyboard VC.
Before, I navigated to the SwiftUI ContentView using a UIHostingController from a UIKit VC.
Does anyone can help me?
Feel free to ask me for other Code/ Screenshots :)
Use UIViewControllerRepresentable
struct UIKitView: UIViewControllerRepresentable {
typealias UIViewControllerType = UIKitViewController
func makeUIViewController(context: Context) -> UIKitViewController {
let sb = UIStoryboard(name: "Main", bundle: nil)
let viewController = sb.instantiateViewController(identifier: "UIKitViewController") as! UIKitViewController
return viewController
}
func updateUIViewController(_ uiViewController: UIKitViewController, context: Context) {
}
}
And then now use
NavigationLink(destination: UIKitView()) { Text("Berlin") }

How to hide UIKit Tabbar in UIViewControllerRepresentable in SwiftUI

I am trying to accessing the Storyboard View Controller in SwiftUI by using UIViewControllerRepresentable. I want to hide the UIKit Tabbar which we applied on ItineraryViewController by using the planDetailViewController.hidesBottomBarWhenPushed = true But that solution not working.
let eventGroup : EventGroup?
func makeUIViewController(context: Context) -> UIViewController {
guard let planDetailViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(identifier: "ItineraryViewController") as? ItineraryViewController else {
fatalError("ViewController not implemented in storyboard")
}
planDetailViewController.userActionMode = .viewOnly
planDetailViewController.itinerary = eventGroup!.event
planDetailViewController.shouldDisableCalendarVC = true
planDetailViewController.hidesBottomBarWhenPushed = true
return planDetailViewController
}
func updateUIViewController(_ uiViewController: UIViewControllerType, context: Context) {
}
}```
Your UIViewControllerRepresentable won't get pushed into a UINavigationController like in UIKit so hidesBottomBarWhenPushed will not be respected.
The best way to do this is using Introspect like in this answer: https://stackoverflow.com/a/64182729/3393964

Pass data from UIViewControllerRepresentable to SwiftUI

I have a UIViewControllerRepresentable like this:
#ObservedObject var viewModel: HomeViewModel
typealias UIViewControllerType = ViewController
func makeUIViewController(context: Context) -> ViewController {
let storyboard = UIStoryboard(name: "ViewController", bundle: Bundle.main)
let viewController = storyboard.instantiateViewController(withIdentifier: "ViewController") as! ViewController
// ...
return viewController
}
func updateUIViewController(_ uiViewController: UIKitInboxDetail, context: Context) {
// ...
}
Inside my viewController there is a collectionView.
Now I would like to detect if my collectionView is scrolled and if so perform some actions.
So i've added this method to my ViewController:
func scrollViewDidEndDecelerating(_ scrollView: UIScrollView) {
if let collectionView = scrollView as? UICollectionView {
isFirstCollectionViewScrolled = true
}
}
But i can access this data only when the view is updated and not at run tiem.
Another approach i've tried is the Coordinator, but I cant perform what I want. Any advice?
Recap: I need to perform some action in my SwiftUI View when a scroll is detected.
Update:
class HomeViewModel: ObservableObject { }
And in my viewController i'm just implementing the usual CollectionView delegates.
If i print somethng in the metod ScrollViewDidEndDegelerating it works! I just neet do something in my swiftUI View when this happened! (A boolean maybe is not the best approach since it set it to true and then it stay true)

Passing Data from SwiftUI View to UIViewController

I've been testing SwiftUI to see how far I can go with it. Now, I want to find out whether or not I can pass a string from SwiftUI View directly to UIViewController. And I want to display this string with UILabel. UILabel is all I have on my storyoboard.
The following is my view controller (UIViewController).
import UIKit
import SwiftUI
class HomeViewController: UIViewController {
var message = String()
#IBOutlet weak var messageLabel: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(animated)
messageLabel.text = message
}
}
struct HomeViewControllerRepresentation: UIViewControllerRepresentable {
func makeUIViewController(context: UIViewControllerRepresentableContext<HomeViewControllerRepresentation>) -> HomeViewController {
UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "homeViewController") as! HomeViewController
}
func updateUIViewController(_ uiViewController: HomeViewController, context: UIViewControllerRepresentableContext<HomeViewControllerRepresentation>) {
}
}
My SwiftUI View is the following.
import SwiftUI
struct ContentView: View {
var body: some View {
NavigationView {
VStack {
NavigationLink(destination: HomeViewControllerRepresentation(message: "GGG")) { // Error
Text("Tap me")
}
}
.navigationBarTitle("")
.navigationBarHidden(true)
}
}
}
I hoped that I could just pass a string with HomeViewControllerRepresentation. But it won't work. Is there a simple way of passing data from SwiftUI View to UIViewController? Thanks.
UIViewControllerRepresentable is not a proxy, but wrapper, so everything should be transferred manually, like
struct HomeViewControllerRepresentation: UIViewControllerRepresentable {
var message: String
func makeUIViewController(context: UIViewControllerRepresentableContext<HomeViewControllerRepresentation>) -> HomeViewController {
let controller = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "homeViewController") as! HomeViewController
controller.message = self.message
return controller
}
func updateUIViewController(_ uiViewController: HomeViewController, context: UIViewControllerRepresentableContext<HomeViewControllerRepresentation>) {
}
}

How to add Storyboard ViewController into SwiftUI Project?

I am working on my SwiftUI Project and every View is now in SwiftUI, however due to some limitations of SwiftUI I have to add Storyboard's ViewControllers into my SwiftUI project. I am trying this method,
struct AssetsListView: UIViewControllerRepresentable {
var taskID : String
public typealias UIViewControllerType = AssetsListViewController
func makeUIViewController(context: UIViewControllerRepresentableContext<AssetsListView>) -> AssetsListViewController {
let assetsListVC = AssetsListViewController()
assetsListVC.taskID = taskID
return assetsListVC
}
func updateUIViewController(_ uiViewController: AssetsListViewController, context: UIViewControllerRepresentableContext<AssetsListView>) {
}
}
This works fine and even viewDidLoad() method of my Storyboard's ViewController calls, but I am unable to see any element on my Storyboard Screen. How can I render those elements? Just like the normal Storyboard stuff.
You just created controller by class initialiser, to instantiate it from storyboard you have to do like the following
func makeUIViewController(context:
UIViewControllerRepresentableContext<AssetsListView>) -> AssetsListViewController {
let storyboard = UIStoryboard(name: "Main", // < your storyboard name here
bundle: nil)
let assetsListVC = storyboard.instantiateViewController(identifier:
"AssetsListViewController") // < your controller storyboard id here
assetsListVC.taskID = taskID
return assetsListVC
}

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