Calculate travel time CLLocation Swift
<p>I want to find travel time of moving object using swift 2.2 when user start  tracking the object. I wrote locationManager function to track the moving object location and travel distance but I need to find travel time?</p>

<pre><code>func locationManager(manager: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
    userLocations.append(locations[0] as CLLocation)

    if startLocation == nil {
        startLocation = locations.first! as CLLocation
    } else {
        let distance = startLocation.distanceFromLocation(locations.last! as CLLocation) / 1000
        let lastDistance = lastLocation.distanceFromLocation(locations.last! as CLLocation) / 1000;

        vartraveledDistance += lastDistance
        print( "\(startLocation)")
        print( "\(locations.last!)")
        print("FULL DISTANCE: \(traveledDistance)")

        print("STRAIGHT DISTANCE: \(distance)")
    }
    lastLocation = locations.last! as CLLocation
}


@IBAction func StartTrip(sender: AnyObject) {
    print("Start Trip")
    locationManager.startUpdatingLocation()
}

@IBAction func StopTrip(sender: AnyObject) {
    print("End Trip")
    locationManager.stopUpdatingLocation()
    traveledDistance.text = String(format:"%f km", self.vartraveledDistance)
}
</code></pre>