_CastError (Null check operator used on a null value) dart-CodePudding

                     onTap: () async {
                        final GoogleMapController controller = await _controller.future;
                        var lat = double.tryParse("-$detailCampus['latitude']")!;
                        var long = double.tryParse("$detailCampus['longitude']")!;
                        controller.animateCamera(
                          CameraUpdate.newCameraPosition(
                            CameraPosition(target: LatLng(lat, long), zoom: 18, tilt: 50, bearing: 45),
                          ),
                        );
                      },

my code has an error, i want to take latitude and longitude from my database. but i had problem double need null checker when i try to use null checker like this

var lat = double.tryParse("-$detailCampus['latitude']")!;
var long = double.tryParse("$detailCampus['longitude']")!;

then i try this one

CameraPosition(target: LatLng(lat!, long!), zoom: 18, tilt: 50, bearing: 45),

but still error.

CodePudding user response：

Try this:

var lat = double.tryParse("-${detailCampus['latitude']}") ?? 0;
var long = double.tryParse("${detailCampus['longitude']}") ?? 0;

Then

CameraPosition(target: LatLng(lat, long), zoom: 18, tilt: 50, bearing: 45),