Get Latitude and longitude center of Google Map - ios

Question

I want to show full screen mapView, always get Latitude and longitude of center of mapView and show marker in this point.
func mapView(_ mapView: GMSMapView, didChange position: GMSCameraPosition) {
let lat = mapView.camera.target.latitude
print(lat)
let lon = mapView.camera.target.longitude
print(lon)
marker.position = CLLocationCoordinate2DMake(CLLocationDegrees(centerPoint.x) , CLLocationDegrees(centerPoint.y))
marker.map = self.mapView
returnPostionOfMapView(mapView: mapView)
}
func mapView(_ mapView: GMSMapView, idleAt position: GMSCameraPosition) {
print("idleAt")
//called when the map is idle
returnPostionOfMapView(mapView: mapView)
}
func returnPostionOfMapView(mapView:GMSMapView){
let geocoder = GMSGeocoder()
let latitute = mapView.camera.target.latitude
let longitude = mapView.camera.target.longitude
let position = CLLocationCoordinate2DMake(latitute, longitude)
geocoder.reverseGeocodeCoordinate(position) { response , error in
if error != nil {
print("GMSReverseGeocode Error: \(String(describing: error?.localizedDescription))")
}else {
let result = response?.results()?.first
let address = result?.lines?.reduce("") { $0 == "" ? $1 : $0 + ", " + $1 }
print(address)
// self.searchBar.text = address
}
}
}
i use this code in how can know Latitude and longitude that return in returnPostionOfMapView method is position of center mapView and show marker in this position?

Answer 1

You are doing it right to get the center of the map by using the google maps's func mapView(_ mapView: GMSMapView, didChange position: GMSCameraPosition) delegate.
Take a variable for center coordinates
var centerMapCoordinate:CLLocationCoordinate2D!
Implement this delegate to know the center position.
func mapView(_ mapView: GMSMapView, didChange position: GMSCameraPosition) {
let latitude = mapView.camera.target.latitude
let longitude = mapView.camera.target.longitude
centerMapCoordinate = CLLocationCoordinate2D(latitude: latitude, longitude: longitude)
self.placeMarkerOnCenter(centerMapCoordinate:centerMapCoordinate)
}
Function to place a marker on center point
func placeMarkerOnCenter(centerMapCoordinate:CLLocationCoordinate2D) {
let marker = GMSMarker()
marker.position = centerMapCoordinate
marker.map = self.mapView
}
In this case you will get a lot of markers. So keep a global hold of marker and check if it is already present, just change the position
var marker:GMSMarker!
func placeMarkerOnCenter(centerMapCoordinate:CLLocationCoordinate2D) {
if marker == nil {
marker = GMSMarker()
}
marker.position = centerMapCoordinate
marker.map = self.mapView
}