#transition #swift

Customtransition.swift

//
//  MenuViewController.swift
//  Mullt
//
//  Created by Marik on 09.03.2020.
//  Copyright © 2020 Marik. All rights reserved.
//

import UIKit

class MenuViewController: UIViewController {
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)

        modalPresentationStyle = .custom
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
    }
 
    
        
    @IBAction func toModule1(_ sender: Any) {
        if let menuController = self.navigationController as? MenuNavigationController {
            let controller = UIStoryboard(name: "Module1", bundle: nil).instantiateInitialViewController()! as! UINavigationController
            menuController.presentNavigationController(controller, animated: false)
        }
    }
    
    
    @IBAction func toModule1Sub(_ sender: Any) {
        if let menuController = self.navigationController as? MenuNavigationController {
            let controller = UIStoryboard(name: "Module1", bundle: nil).instantiateInitialViewController()! as! UINavigationController
            menuController.presentNavigationController(controller, animated: true)
        }
    }
    
}

class MenuNavigationController: UINavigationController {
    var customTransitionDelegate = TransitionDelegate()
    
    weak var presentedController: UINavigationController?
    var interactiveTransition: UIPercentDrivenInteractiveTransition?
    
    
    func presentNavigationController(_ navController: UINavigationController, animated: Bool) {
        navController.modalPresentationStyle = .custom
        navController.transitioningDelegate = self.customTransitionDelegate
        if let firstController = navController.viewControllers.first {
            let panDown = UIPanGestureRecognizer(target: self, action: #selector(handleDissmiss(_:)))
            firstController.view.addGestureRecognizer(panDown)
        }
        self.present(navController, animated: animated) {
            self.presentedController = navController
        }
    }
    
    @objc func handleDissmiss(_ gesture: UIPanGestureRecognizer) {
        let translate = gesture.translation(in: gesture.view)
        let percent = translate.x / gesture.view!.bounds.size.width
        if gesture.state == .began {
            if gesture.location(in: gesture.view).x / gesture.view!.bounds.size.width < 0.3 {
                interactiveTransition = UIPercentDrivenInteractiveTransition()
                customTransitionDelegate.interactionController = interactiveTransition
                self.dismiss(animated: true, completion: nil)
            }
        } else if gesture.state == .changed {
            interactiveTransition?.update(percent)
        } else if gesture.state == .ended || gesture.state == .cancelled {
            let velocity = gesture.velocity(in: gesture.view)
            if percent > 0.5 || velocity.x > 500 {
                interactiveTransition?.finish()
            } else {
                interactiveTransition?.cancel()
            }
            interactiveTransition = nil
        }
    }
    
}