Compose UI component in SwiftUI that respects intrinsic sizing

00_ComposeViewController.kt

private fun measuredViewController(
    onMeasured: (Double, Double) -> Unit,
    content: @Composable () -> Unit,
): UIViewController = ComposeUIViewController {
    Box(
        modifier = Modifier.onGloballyPositioned {
            onMeasured(it.size.width.toDouble(), it.size.height.toDouble())
        },
    ) {
        content()
    }
}

0_Badge.kt

fun _Badge(
    count: Int,
    onMeasured: (Double, Double) -> Unit,
): UIViewController = measuredViewController(onMeasured = onMeasured) {
    Badge(count = count)
}

1_MeasuredView.swift

struct MeasuredView<Content: View>: View {
    
    @State public var measuredWidth: CGFloat = 1000.0
    @State var measuredHeight: CGFloat = 1000.0
    
    var content: (Binding<CGFloat>, Binding<CGFloat>) -> Content
    
    init(@ViewBuilder content: @escaping (Binding<CGFloat>, Binding<CGFloat>) -> Content) { self.content = content }
    
    var body: some View {
        content($measuredWidth, $measuredHeight)
            .frame(width: measuredWidth / UIScreen.main.scale, height: measuredHeight / UIScreen.main.scale)
    }
}

2_UIViewControllerRepresentable.swift

private struct BadgeCountViewControllerRepresentable : UIViewControllerRepresentable {
    
    @State public var count: Int32
    @Binding var measuredWidth: CGFloat
    @Binding var measuredHeight: CGFloat

    public func makeUIViewController(context: Context) -> UIViewController {
        ComponentsKt._Badge(count: count) { w, h in
            measuredWidth = CGFloat(truncating: w)
            measuredHeight = CGFloat(truncating: h)
        }
    }

    public func updateUIViewController(_ uiViewController: UIViewController, context: Context) {
    }
}

3_Badge.swift

public struct Badge: View {
    
    let count: Int32
    
    public var body: some View {
        MeasuredView(
            content: { w, h in
                BadgeCountViewControllerRepresentable(
                    count: count,
                    measuredWidth: w,
                    measuredHeight: h
                )
            }
        )
    }
}

4_ContentView.swift

HStack {
   Badge(count: 3)
}