如何在 google_maps_flutter 中获取当前的纬度和经度？

Question

How can I get the LatLng of user's current location when using google_maps_flutter plugin?

I wish there had been something like:

GoogleMap(
  onLocationChanged: (latLng) {
    // Something like this callback ...
  }
)

PS: I don't wish to use any other plugin.

Answer 1

Flutter is a framework which allows you to create UI easily. But behind this technology actually we don't have any native functionality. To bring these functionalities to flutter we have "Method Channel" or "Dart:FFI".

If you look at the source code of plugin which brings native functions to flutter they mostly use "Method Channel".

Google Maps plugin allows you to use google maps api, but however if you want to use or get client location, you must have some native code.

Some 3rd party apps already offer this functionality for you, but if you want to develop it for yourself, you have to write your own code for Android & iOS. Then you need to link it with the flutter. To do this you need to use method channel .

Answer 2

Maybe what you need is the location package from Flutter dev.

With that you can just listen for location changes, and maybe update your current location variable.

Something like:

location.onLocationChanged().listen((LocationData newLoc) {
  currentLocation = newLoc;
});

Answer 3

There is no way to get current location from google_maps_flutter plugin, but you can get displaying location either by

GoogleMap(
   onCameraMove: (LatLng displayingLocation){
      // do operations here
   }
)

or by using map controller

mapController.getLatLng(ScreenCoordinate(
        x: MediaQuery.of(context).size.width, 
        y: MediaQuery.of(context).size.height))