ios - User Tracking Mode Missing Animation, Swift -

i have code here including usertrackingmode = .follow , works great pops onto userlocation instead of animating map go user location ...which want . can tell me hot add animation making map change onto user location animation , not pop onto ( if makes sense )

import uikit import mapkit import corelocation  class mapviewcontroller: uiviewcontroller,mkmapviewdelegate, cllocationmanagerdelegate{      @iboutlet weak var mapview: mkmapview!      @ibaction func usertrackingmode(sender: anyobject) {          mapview.usertrackingmode = .follow     } 

you can call setusertrackingmode:animated in order animate transition:

@ibaction func usertrackingmode(sender: anyobject) {      mapview.setusertrackingmode(.follow, animated:true) }