swift - how to delete google maps markers from previous session before app is opened again?
<p>What I am trying to accomplish:</p>

<pre><code>    open app to see a clear google map view
    place a marker on map
    if the app is navigated away from(i.e. pressing the home button or double pressing home button to go to different app)
        clear all markers on map
</code></pre>

<p>Right now the markers are being stored and saved until i open the app again, but i would like to have them cleared if the app is navigated away from.</p>

<pre><code>override func viewDidLoad() {
    super.viewDidLoad()

    //thought this could possibly clear any previous markers before app fully runs again
    self.googleMapView.clear()

    self.locationManager.requestAlwaysAuthorization()
    self.locationManager.requestWhenInUseAuthorization()

    if CLLocationManager.locationServicesEnabled() {
        locationManager.delegate = self
        locationManager.desiredAccuracy = kCLLocationAccuracyBest
        locationManager.startMonitoringSignificantLocationChanges()
    }

}

override func viewDidAppear(animated: Bool) {
    super.viewDidAppear(animated)
    self.googleMapView = GMSMapView(frame: self.mapViewContainer.frame)
    self.view.addSubview(self.googleMapView)

}
</code></pre>