title: how to show mapkit blue dot(user's location) at desired location?
body: <p>I am using MapKit. I want to know how to get current user's location. The MapKit shows a blue dot at current user location.</p>
  
  <p>I want to do something like this: The user location is showed on the map. I have a button which, on clicking again, gets the current user location and shows the blue dot there.</p>
  
  <p>Do I need to use <code>locationManager</code> or just call the <code>mapView.showUserLocation=YES;</code> on the button's click event?</p>