SwiftUI UIScrollView content can be scrolled out of frame - swiftui

Question

I implemented a UIScrollView from UIKit in SwiftUI (without storyboard) because there is nothing similar in SwiftUI. It works quite well so far, but the ScrollView is not limited by the size of the content, but you can still scroll over the edge of the content. The stronger the zoom factor, the stronger this effect becomes apparent.
UIScrollView Wrapper in SwiftUI:
struct ZoomableScrollView<Content: View>: UIViewRepresentable {
#Binding var didZoom: Bool
private var content: Content
init(didZoom: Binding<Bool>, #ViewBuilder content: () -> Content) {
_didZoom = didZoom
self.content = content()
}
func makeUIView(context: Context) -> UIScrollView {
let scrollView = UIScrollView()
scrollView.delegate = context.coordinator
scrollView.maximumZoomScale = 20
scrollView.minimumZoomScale = 1
scrollView.bouncesZoom = true
let hostedView = context.coordinator.hostingController.view!
hostedView.translatesAutoresizingMaskIntoConstraints = true
hostedView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
hostedView.frame = scrollView.bounds
hostedView.backgroundColor = .black
scrollView.addSubview(hostedView)
return scrollView
}
func makeCoordinator() -> Coordinator {
return Coordinator(hostingController: UIHostingController(rootView: self.content), didZoom: $didZoom)
}
func updateUIView(_ uiView: UIScrollView, context: Context) {
context.coordinator.hostingController.rootView = self.content
assert(context.coordinator.hostingController.view.superview == uiView)
}
class Coordinator: NSObject, UIScrollViewDelegate {
var hostingController: UIHostingController<Content>
#Binding var didZoom: Bool
init(hostingController: UIHostingController<Content>, didZoom: Binding<Bool>) {
self.hostingController = hostingController
_didZoom = didZoom
}
func viewForZooming(in scrollView: UIScrollView) -> UIView? {
return hostingController.view
}
func scrollViewDidEndZooming(_ scrollView: UIScrollView, with view: UIView?, atScale scale: CGFloat) {
didZoom = !(scrollView.zoomScale == scrollView.minimumZoomScale)
}
}
}
SwiftUI ContentView:
struct ContentView: View {
var body: some View {
ZoomableScrollView {
Rectangle()
.frame(width: 420, height: 600)
}
}
}

Answer 1

You're making whole screen zoomable if you want to make only rectangle zoomable then only wrap that rectangle within zoomablescrollview
struct ContentView: View {
var body: some View {
ZStack{
ZoomableScrollView {
Rectangle()
.frame(width: 420, height: 600)
}.frame(width: 420,height: 600)
}
}
}