SwiftUI Popover

popoversample

class PopupViewController:UIViewController{
	let frame:CGRect
	let content:AnyView
	
	required init?(coder: NSCoder) {
		fatalError("init(coder:) has not been implemented")
	}
	
	
	override func viewDidLoad() {
        super.viewDidLoad()

		createPopup()
    }
	
	func  createPopup(){
		let hostingViewController = UIHostingController(rootView: content)
		
		hostingViewController.modalPresentationStyle = .popover
		hostingViewController.popoverPresentationController?.delegate = self
		hostingViewController.popoverPresentationController?.sourceView = self.view
		hostingViewController.popoverPresentationController?.sourceRect = frame
		
		hostingViewController.view.backgroundColor = nil
		
		// need to manually set preferredContentSize for the popover
		// but thankfully we can use sizeThatFits(:) to force the SwiftUI view to size itself
		let popoverMaxSize = CGSize(width: 250, height: 500)
		hostingViewController.preferredContentSize = hostingViewController.sizeThatFits(in: popoverMaxSize)
	}
	
	init(frame:CGRect,content:AnyView) {
		self.frame = frame
		self.content = content
		super.init(nibName: nil, bundle:nil)
	}
}

extension PopupViewController: UIPopoverPresentationControllerDelegate {
	
    func adaptivePresentationStyle(for controller: UIPresentationController) -> UIModalPresentationStyle {
        return .none // this is what forces popovers on iPhone
    }
}

struct PopupRepresentation:UIViewControllerRepresentable{
	var frame:CGRect
	var view:AnyView
	
	func makeUIViewController(context: Context) -> UIViewController {
		let vc = PopupViewController(frame: frame, content:view)
		return vc
	}
	
	func updateUIViewController(_ uiViewController: UIViewController, context: Context) {
	print("update")
	}
	
	typealias UIViewControllerType = UIViewController

}

struct ContentView: View {
	typealias PopoverPresenter = (CGRect, AnyView) -> Void
	
	var showPopover: PopoverPresenter?
	
	var body: some View {
		VStack {
			Spacer()
			MeasuredButton(action: { frame in
				let view = PopoverView(text: "This popover has determined its size based on its content and appears to be presented from a SwiftUI button.")
				self.showPopover?(frame, AnyView(view))

			}) {
				Text("Show Popover")
			}
		}.padding()
	}
}


struct PopoverView: View {
	@State var text:String
	
	var body: some View {
		Text(text)
			.padding()
	}
}


struct ContentView_Previews: PreviewProvider {
	static var previews: some View {
		ContentView()
	}
}