【Xcode/Swift】How to use UICalendarView in UIKit

It’s available from iOS16.

UIKit

import UIKit

class HomeViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        configureCalenderView()
    }

    private func configureCalenderView() {
        view.backgroundColor = .white
        let selection = UICalendarSelectionSingleDate(delegate: self)
        let calendarView = UICalendarView()
        calendarView.frame = view.bounds
        calendarView.delegate = self
        calendarView.selectionBehavior = selection
        view.addSubview(calendarView)
    }

}

extension HomeViewController: UICalendarViewDelegate {}

extension HomeViewController: UICalendarSelectionSingleDateDelegate {
    func dateSelection(_ selection: UICalendarSelectionSingleDate, didSelectDate dateComponents: DateComponents?) {
        guard let dateComponents = dateComponents,
              let year = dateComponents.year,
              let month = dateComponents.month,
              let day = dateComponents.day else {
            return
        }
        print("Year: \(year), Month: \(month), Day: \(day)")
    }
}

SwiftUI

CalendarView

import SwiftUI

struct CalendarView: UIViewRepresentable {
    let didSelectDate: (_ dateComponents: DateComponents) -> Void

    final public class Coordinator: NSObject, UICalendarSelectionSingleDateDelegate {
        let didSelectDate: (_ dateComponents: DateComponents) -> Void

        init(
            didSelectDate: @escaping (_ dateComponents: DateComponents) -> Void
        ) {
            self.didSelectDate = didSelectDate
        }

        public func dateSelection(_ selection: UICalendarSelectionSingleDate, didSelectDate dateComponents: DateComponents?) {
            guard let dateComponents = dateComponents else {
                return
            }
            didSelectDate(dateComponents)
        }
    }

    public func makeCoordinator() -> Coordinator {
        Coordinator(didSelectDate: didSelectDate)
    }

    func makeUIView(context: Context) -> some UIView {
        let selection = UICalendarSelectionSingleDate(delegate: context.coordinator)

        let calendarView = UICalendarView()
        calendarView.selectionBehavior = selection
        return calendarView
    }

    func updateUIView(_ uiView: UIViewType, context: Context) {}
}

struct CalendarView_Previews: PreviewProvider {
    static var previews: some View {
        CalendarView { dateComponents in
        }
    }
}

HomeView

import SwiftUI

struct HomeView: View {
    var body: some View {
        CalendarView { dateComponents in
            guard let year = dateComponents.year,
                  let month = dateComponents.month,
                  let day = dateComponents.day else {
                return
            }
            print("Year: \(year), Month: \(month), Day: \(day)")
        }
    }
}

struct HomeView_Previews: PreviewProvider {
    static var previews: some View {
        HomeView()
    }
}

Reference