Hi, I have tried the library it is very perfectly if I am adding an UILabel or UIView. But now I am trying to add UIActivityIndicatorView, seems it doesn't work. Is this syntax below correct ?. I tried this but the view is not showing anything, but once I try with UILabel or UIView, it works fine.

UIActivityIndicatorView(style: .large)
                .swiftUIView(layout: .fixed(size: CGSize(width: 100, height: 100)))
                .set(\.color, to: UIColor.blue)
                .set(\.isHidden, to: false)
                .fixedSize()

second question, how did I trigger a function that preserved from one of the subclass of UIView ? Let say this activity indicator has an open function called as startAnimating(). however I can't using the declarative syntax in above code, is it expected to only set a value but can't call any derived method ?

Thank you before, @AvdLee

public struct ContentView: View {
        var body: some View {
                return AnyView(
                        ViewController().view
                                .swiftUIView(layout: .intrinsic)
                )
        }
}

class ViewController: UIViewController {
	
	var scrollView = UIScrollView()
	let contentView = UIView()
	var pullControl = UIRefreshControl()
	
	override func viewDidLoad() {
		super.viewDidLoad()
		
		setupScrollView()
		setupViews()
	}
	
	@objc func handleRefreshControl() {
		// Update your content…
		print("hi")
		// Dismiss the refresh control.
		DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
			self.scrollView.refreshControl?.endRefreshing()
		}
	}
	
	func setupScrollView(){
		scrollView.translatesAutoresizingMaskIntoConstraints = false
		contentView.translatesAutoresizingMaskIntoConstraints = false
		
		view.addSubview(scrollView)
		scrollView.addSubview(contentView)
		
		scrollView.centerXAnchor.constraint(equalTo: view.centerXAnchor).isActive = true
		scrollView.widthAnchor.constraint(equalTo: view.widthAnchor).isActive = true
		scrollView.topAnchor.constraint(equalTo: view.topAnchor).isActive = true
		scrollView.bottomAnchor.constraint(equalTo: view.bottomAnchor).isActive = true
		scrollView.backgroundColor = UIColor.red
		
		scrollView.refreshControl = pullControl
		
		
		scrollView.refreshControl?.addTarget(self, action:
												#selector(handleRefreshControl),
											 for: .valueChanged)
		
		
		contentView.centerXAnchor.constraint(equalTo: scrollView.centerXAnchor).isActive = true
		contentView.widthAnchor.constraint(equalTo: scrollView.widthAnchor).isActive = true
		contentView.topAnchor.constraint(equalTo: scrollView.topAnchor).isActive = true
		contentView.bottomAnchor.constraint(equalTo: scrollView.bottomAnchor).isActive = true
	}
	
	func setupViews(){
		child.view.sizeToFit()
		child.view.translatesAutoresizingMaskIntoConstraints = false
		contentView.addSubview(child.view)
		child.view.centerXAnchor.constraint(equalTo: contentView.centerXAnchor).isActive = true
		child.view.topAnchor.constraint(equalTo: contentView.topAnchor).isActive = true
		child.view.widthAnchor.constraint(equalTo: contentView.widthAnchor).isActive = true
		child.view.bottomAnchor.constraint(equalTo: contentView.bottomAnchor).isActive = true
	}
	
	let child: UIHostingController = UIHostingController(rootView: TestView())
}

public struct TestView : View {
	public var body: some View {
		VStack {
			Group {
				Text("Test1")
				Text("Test2")
				Text("Test3")
				Text("Test4")
				Text("Test5")
				Text("Test6")
				Text("Test7")
				Text("Test8")
				Text("Test9")
				Text("Test10")
			}
		}
	}
}

When I swipe to refresh, refreshData isn't being called. The refresh animation plays endlessly. However, my code works when it isn't embedded in a SwiftUI view. Is this issue fixable?

struct ContentView: View {
    @State var counter = 0
    
    var body: some View {
        VStack {
            
            Text("Hello no \(counter) from SwiftUI")
                .padding()
            
            UILabel() // <- This can be any `UIKit` view.
                .swiftUIView(layout: .intrinsic) // <- This is returning a SwiftUI `View`.
                .set(\.text, to: "Hello no \(self.counter) from UIKit") // <- Use key paths for updates.
                .fixedSize()
        }
        .onAppear {
            if counter == 0 {
                schedule()
            }
        }
    }
    
    func schedule() {
        counter += 1
        DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
            self.schedule()
        }
    }
}

I expected the UILabel to be updated and behave like my SwiftUI Text-view, but instead it is showing just 0. Also, recreating the UILabel every time the view hierarchy is declared is not a good idea as it may happen many many times. I think this is a fundamental issue with the approach in this library. I find this approach better and easier

import SwiftUI
import UIKit

struct UIViewMaker<ViewType: UIView>: UIViewRepresentable {
    
    typealias UIViewType = ViewType
    
    var make: () -> ViewType = ViewType.init
    var update: (ViewType) -> ()
    
    func makeUIView(context: Context) -> ViewType {
        return make()
    }
    
    func updateUIView(_ uiView: ViewType, context: Context) {
        update(uiView)
    }
}

struct ContentView: View {
    @State var counter = 0
    
    var body: some View {
        VStack {
            
            Text("Hello no \(counter) from SwiftUI")
                .padding()
            
            
            UIViewMaker<UILabel> {
                $0.text = "Hello no \(self.counter) from UIKit"
            }
            .fixedSize()
            
        }
        .onAppear {
            if counter == 0 {
                schedule()
            }
        }
    }
    
    func schedule() {
        counter += 1
        DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
            self.schedule()
        }
    }

}

I initially built SwiftUIKitView to create previews for UIKit views quickly. Though, many started using this framework in production code, for which it was not optimized.

Code changes in this PR do optimize for production, making it easier to use UIKit views in production apps.

Fixes #2 Fixes #3

UILabel Preview Example in project SwiftUIKitExample.xcodeproj does not work.

        UILabel() // <- This is a `UIKit` view.
            .swiftUIView(layout: .intrinsic) // <- This is a SwiftUI `View`.
            .set(\.text, to: "Hello, UIKit!") // <- Use key paths for updates.
            .fixedSize() // <- Make sure the size is set
            .previewLayout(.sizeThatFits)
            .previewDisplayName("UILabel Preview Example")
    }

Expected to see the text "Hello, UIKit!" but that text is not visible in the preview :(

https://user-images.githubusercontent.com/4176826/193900800-b6b01da1-5898-43b8-a3a8-2606e380f04c.mov

Tested with Xcode 14.0.1 and iPhone 13 (iOS 16) simulator

This PR leverages dynamicMemberLookup to allow setting properties in the same style as SwiftUI.

Unfortunately DML cannot be implemented by a protocol so the implementation needs to be duplicated between the conforming types (UIViewContainer and ModifiedUIViewContainer)