Swift 3.0 Map Returns to Previous MapView

Question

I have a mapView with annotations with detail disclosure that when clicked on, moves to a new viewController. Then when the user selects to go back to the mapView from the detail disclosure, I want the mapView to have the same view that the user had before clicking on the detail disclosure. Below is the code I have set up so far, however, when the user clicks back from the detail disclosure, the map zooms out. I am not sure how to recreate the previous view.

Detail Disclosure VC:

// here by segueing, I want to communicate to the MapView VC that the map should remain the same  
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
    if (segue.identifier == "backButtonTapped" )
    {
        let destinationVC = segue.destination as! TabBarVC
        mapStatus = "wentBack"
        print("The value of mapStatus after seguing is \(mapStatus)")
        destinationVC.selectedIndex = 1

    }

}

MapView VC:

 override func viewDidAppear(_ animated: Bool) {
    // here if the mapStatus is not the correct value (the user never used the detail disclosure), the map will just snap onto the current location

    if mapStatus == "wentBack" {
       print("Do not update location")

       // assuming appropriate code is placed here but I am not sure what it is


    } else {
        print("Updated Current Location")
    let center = CLLocationCoordinate2D(latitude: self.lastLocation.coordinate.latitude, longitude: self.lastLocation.coordinate.longitude)
    let region = MKCoordinateRegion(center: center, span: MKCoordinateSpan(latitudeDelta: 0.01, longitudeDelta: 0.01))

    map.setRegion(region, animated: true)

        locationManager.delegate = self
        locationManager.desiredAccuracy = kCLLocationAccuracyBest
        if #available(iOS 8.0, *) {
            locationManager.requestAlwaysAuthorization()
        } else {
            // Fallback on earlier versions
        }
        let noLocation = CLLocationCoordinate2D()
        let viewRegion = MKCoordinateRegionMakeWithDistance(noLocation, 200, 200)
        map.setRegion(viewRegion, animated: false)

    }
    }

Answer 1

So it turns out that the map does not persist because viewDidLoad is being called when the user hits back on the detail disclosure (using a prepareForSegue). I used

@IBAction func backButtonTapped(_ sender: UIBarButtonItem) {
    self.dismiss(animated: true)
    mapStatus = "wentBack"

} 

In order to just dismiss the viewController, and only calling viewDidAppear and not viewDidLoad.