Question

我已经提到了其他堆栈溢出问题，但似乎找不到适用于我的解决方案。我试图显示动态的谷歌地图，但是即使我已授予许可权，fetlocation（）方法也返回null，而且在consol中也没有看到我要打印的代码。这是代码：

 Future<bool> assignService(Location loc) async {
  bool servicestatus = await loc.serviceEnabled();
  print("Service status $servicestatus");
  return servicestatus;
}

Future<PermissionStatus> assignPermission(Location loc) async {
  var hasPermission = await loc.hasPermission();
  print("Permission status $hasPermission");
  return hasPermission;
}

Location location = Location();

var _serviceEnabled;
var _serve = assignService(location).then((value) => _serviceEnabled = value);

//var _permissionGranted = assignPermission(location);
var _permissionGranted;
var _permi = assignPermission(location).then((value) => _permissionGranted = value);

void startService(){
if (!_serviceEnabled) {
  _serviceEnabled = assignService(location);
  print("service disabled");
  if (!_serviceEnabled) {
    return;
  }
}

if (_permissionGranted == PermissionStatus.denied){
  _permissionGranted = assignPermission(location);
  print("permission denied");
  if (_permissionGranted != PermissionStatus.granted) {
    return;
  }
}
} 

var map;

final mapp = location.getLocation().then((value) => map = value);



class NearbyScreen extends StatelessWidget {

  @override
  //LocationHelper.mapviewpointer(latitude: )

  Widget build(BuildContext context) {
    return /* !_serviceEnabled ? Center(child:Text("Page cannot be viewed"),) :*/
        map == null
            ? Center(
                child: Text("Null response"),
              )
            : GoogleMap(
                initialCameraPosition: CameraPosition(
                    target: LatLng(map.latitude, map.longitude
/* double.parse(coordinates[0]), double.parse(coordinates[1]) */)),
                minMaxZoomPreference: MinMaxZoomPreference(10, 20),
                zoomControlsEnabled: true,
              );
  }
}

从flutter中的getlocation（）方法返回null？

0 个答案: