xib로 View를 만들었습니다.

기능 설명

 pod 'FSCalendar'

FSCalendar

import Foundation
import FSCalendar

class FSCalendarModel:UIViewController{

    let fsCalendar = FSCalendar()

    func createCalemdar(x: CGFloat, y: CGFloat, width: CGFloat, height: CGFloat, targetView:UIView){

        self.fsCalendar.frame = CGRect(x: x, y: y, width: width, height: height)

        targetView.addSubview(self.fsCalendar)

    }
}

보기

import Foundation
import UIKit

class ModalView:UIViewController{

    @IBOutlet weak var partsView: UIView!
    @IBOutlet weak var calendarView: UIView!

    let fsCalendarModel = FSCalendarModel()

    override func viewDidLoad() {
        super.viewDidLoad()

    }

    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)

        self.partsView.layer.cornerRadius = 22.0
        self.calendarView.layer.cornerRadius = 22.0

        self.fsCalendarModel.createCalemdar(x: 0, y: 0, width: self.calendarView.frame.size.width, height: self.calendarView.frame.size.height, targetView: self.calendarView)     

    }
}

컨트롤러

import UIKit

class ViewController: UIViewController, UIViewControllerTransitioningDelegate {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view.
    }

    @IBAction func show(_ sender: Any) {

        let modalView = ModalView()
        modalView.modalPresentationStyle = .automatic
        modalView.transitioningDelegate = self
        present(modalView, animated: true, completion: nil)

    }

}

끝