viewController Present when I dismissed it - ios

Question

I have a viewcontroller which is segue to a tableViewController and I want to present it with transition and as a sideMenu from top I find some code and it's working fine but i cant understand the part when i dismiss the ViewController it present itself
//
// ViewController.swift
// ProTansition
//
// Created by Teodik Abrami on 11/1/18.
// Copyright © 2018 Teodik Abrami. All rights reserved.
//
import UIKit
class ViewController: UIViewController, MenuTransitionManagerDelegate {
func dismiss() {
dismiss(animated: true, completion: nil)
print("dismiss run")
}
var menuTransition = MenuTransitionManager()
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewDidAppear(_ animated: Bool) {
print("ViewController Appear")
}
override func viewDidDisappear(_ animated: Bool) {
print("viewcontroller disapear")
}
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
let destinaion = segue.destination
destinaion.transitioningDelegate = menuTransition
menuTransition.delegate = self
}
}
tableView is a normal tableview with 5 rows and no special code in it
and the transition
//
// MenuTransitionManager.swift
// ProTansition
//
// Created by Teodik Abrami on 11/1/18.
// Copyright © 2018 Teodik Abrami. All rights reserved.
//
import Foundation
import UIKit
#objc protocol MenuTransitionManagerDelegate {
func dismiss()
}
class MenuTransitionManager: NSObject, UIViewControllerAnimatedTransitioning, UIViewControllerTransitioningDelegate {
let duration = 2.0
var isPresenting = false
var delegate: MenuTransitionManagerDelegate?
var snapShot: UIView? {
didSet {
if let delegate = delegate {
let tap = UITapGestureRecognizer(target: delegate, action: #selector(delegate.dismiss))
snapShot?.addGestureRecognizer(tap)
}
}
}
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return duration
}
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
guard let fromView = transitionContext.view(forKey: UITransitionContextViewKey.from) else {
return
}
guard let toView = transitionContext.view(forKey: UITransitionContextViewKey.to) else {
return
}
let container = transitionContext.containerView
let moveDown = CGAffineTransform.init(translationX: 0, y: container.frame.height - 150)
if isPresenting {
container.addSubview(toView)
snapShot = fromView.snapshotView(afterScreenUpdates: true)
container.addSubview(snapShot!)
}
UIView.animateKeyframes(withDuration: duration, delay: 0, options: [], animations: {
if self.isPresenting {
self.snapShot?.transform = moveDown
} else {
self.snapShot?.transform = CGAffineTransform.identity
}
}) { (finished) in
transitionContext.completeTransition(true)
if !self.isPresenting {
self.snapShot?.removeFromSuperview()
}
}
}
func animationController(forPresented presented: UIViewController, presenting: UIViewController, source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
isPresenting = true
return self
}
func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
isPresenting = false
return self
}
}
I add tapgesture to snapshot and when its tapped protocol works and dismiss in viewcontroller works and the viewController appears I dont understand why and even why codes run on a controller that are not presented
this is the view controller that i cant figured out why it present when i dismiss it
this happend when menuButton pressed

Answer 1

Your whole strategy of setting isPresenting = true or isPresenting = false is doomed to failure, as both pieces of code will run on both occasions. You have to distinguish presentation from dismissal by using two different animationController objects (instead of returning self both times) or by looking to see which view controller is the from view controller and which is the to view controller.