Get latitude and longitude of icon place in google map - google-maps

Question

In my flutter app. I am using google_maps_plugin . The link is https://github.com/flutter/plugins/tree/master/packages/google_maps_flutter .
I want to fix the marker in center of map without moving of icon after drag the map. I successfully done by using stack . But my question is how to get the longitude and latitude of icon I placed in stack .
I want it likes http://jsfiddle.net/UuDA6/
The code is shown below.
class MyApp extends StatelessWidget {
MyApp();
#override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'Title',
theme: new ThemeData(
primarySwatch: Colors.blue,
),
home: new AppPage(title: 'Augr'),
);
}
}
class AppState extends InheritedWidget {
const AppState({
Key key,
this.mode,
Widget child,
}) : assert(mode != null),
assert(child != null),
super(key: key, child: child);
final Geocoding mode;
static AppState of(BuildContext context) {
return context.inheritFromWidgetOfExactType(AppState);
}
#override
bool updateShouldNotify(AppState old) => mode != old.mode;
}
class AppPage extends StatefulWidget{
AppPage() : super(key: key);
#override
_AppPageState createState() => new _AppPageState();
}
class _AppPagePageState extends State<MyApp> {
_AppPagePageState();
List<Address> results = [];
String address;
String googleMapsApiKey = 'APIKEY';
GoogleMapController mapController;
Position position;
#override
Widget build(BuildContext context){
return new Scaffold(
appBar: null,
body: Padding(
padding: EdgeInsets.only(top: 25.0),
child:Column(
children: <Widget>[
SizedBox(
width: 200,
height: 300,
child: Stack(
children: <Widget>[
GoogleMap(
onMapCreated: _onMapCreated,
),
InfoView()
],
),
),],
)
),
);
}
void initState() {
super.initState();
}
void _onMapCreated(GoogleMapController controller) {
setState(() {
mapController = controller;
mapController.animateCamera(CameraUpdate.newCameraPosition(
CameraPosition(
bearing: 270.0,
target: LatLng(lattitude, longitude),
tilt: 30.0,
zoom: 17.0,
),
));
});
}
}
class InfoView extends StatelessWidget {
const InfoView({
Key key,
}) : super(key: key);
#override
Widget build(BuildContext context) {
return new Align(
alignment: Alignment.center,
child: new Icon(Icons.person_pin_circle, size: 40.0), //This the icon showing in google map .
);
}
}
The infoView() is defined the icon to show overlap in google map. I want to fetch the latitude and longitude of the icon place in map.
If any one have the idea about it please share it.