Using SwiftUI in UIKit as UIViewController

The good thing about SwiftUI is you can gradually adopt it. We can use SwiftUI view in UIKit by turning it to UIViewController.

In this article, I will show you how to integrate SwiftUI view as a UIViewController.

How to use SwiftUI View as UIViewController

To use SwiftUI view as a UIViewController, we need help from UIHostingController.

UIHostingController is a view controller that wrap a SwiftUI view so it can be used in the UIKit project.

To wrap a SwiftUI view inside a UIHostingController, we specify it in the initializer. This specified view will used as the root view for the hosting view controller.

I create a simple SwiftUI view as an example.

struct SwiftUIView: View {
    var body: some View {
        Text("Hello, SwiftUI!")
            .font(.title)
            .buttonStyle(.borderedProminent)
    }
}

I can use it in UIKit like this.

import SwiftUI

let vc = UIHostingController(rootView: SwiftUIView())

You can easily support sarunw.com by checking out this sponsor.

Tiny OCR: Extract text from image directly from your mac.

Try it for Free

Bridging between SwiftUI view and UIViewController

UIHostingController does a good job bridging between SwiftUI and UIKit. You can use any SwiftUI feature, and it will seamlessly translate into the UIKit world.

As an example, I will create a SwiftUI view and push it to a UINavigationController.

struct SwiftUIView: View {
    // 1
    @Environment(\.dismiss) private var dismiss

    var body: some View {
        VStack {
            Text("Hello, SwiftUI!")
                .font(.title)
                .buttonStyle(.borderedProminent)
            Button("Dismiss") {
                // 2
                dismiss()
            }
        }
        // 3
        .navigationTitle("SwiftUI")
    }
}

1 I add @Environment(\.dismiss) to pop our view out of a navigation stack when users tap the dismiss button 2.
3 I also set a navigation title using .navigationTitle("SwiftUI") modifier.

Then, we push our SwiftUI view when the button is tapped.

@IBAction func didTapButton(_ sender: Any) {
    let vc = UIHostingController(rootView: SwiftUIView())
    
    navigationController?.pushViewController(vc, animated: true)
}

Here is the result. As you will see

• We can pop the SwiftUI view out of UINavigationController using SwiftUI dismissal action, @Environment(\.dismiss).
• The navigation title set with the .navigationTitle modifier also takes effect in UIKit.