Unhandled Exception: Invalid argument: is a regular instance: Instance of 'LocationDto' - flutter

Question

currently I am us this plugin to get the background location of a user, works great with ios but fails on android after recent updates and the plugin progress stalled, I am now faced with the issue below
so, in my main class i have this
#override
void initState() {
super.initState();
WidgetsBinding.instance.addObserver(this);
// onLineStatus = UserSimplePreferences.getUsername() ?? ''
onLineStatus = UserSimplePrefences.getButtonStatus() ?? false;
displayToastMessage(onLineStatus.toString(), context);
osmController = MapController(
initMapWithUserPosition: true,
//initPosition: initPosition,
);
osmController.addObserver(this);
scaffoldKey = GlobalKey<ScaffoldState>();
if (IsolateNameServer.lookupPortByName(
LocationServiceRepository.isolateName) !=
null) {
IsolateNameServer.removePortNameMapping(
LocationServiceRepository.isolateName);
}
IsolateNameServer.registerPortWithName(
port.sendPort, LocationServiceRepository.isolateName);
port.listen(
(dynamic data) async {
if (data != null) await updateUI(data);
},
);
initPlatformState();
}
Future<void> updateUI(LocationDto data) async {
await _updateNotificationText(data);
}
Future<void> _updateNotificationText(LocationDto data) async {
await BackgroundLocator.updateNotificationText(
title: "Your location is updated",
msg: "${DateTime.now()}",
bigMsg: "${data.latitude}, ${data.longitude}");
}
Future<void> initPlatformState() async {
print('Initializing...');
await BackgroundLocator.initialize();
await BackgroundLocator.isServiceRunning();
}
Future<void> _startLocator() async {
Map<String, dynamic> data = {'countInit': 1};
return await BackgroundLocator.registerLocationUpdate(
LocationCallbackHandler.callback,
initCallback: LocationCallbackHandler.initCallback,
initDataCallback: data,
disposeCallback: LocationCallbackHandler.disposeCallback,
iosSettings: IOSSettings(
accuracy: LocationAccuracy.NAVIGATION,
distanceFilter: 0,
stopWithTerminate: true),
autoStop: false,
androidSettings: AndroidSettings(
accuracy: LocationAccuracy.NAVIGATION,
interval: 5,
distanceFilter: 0,
client: LocationClient.google,
androidNotificationSettings: AndroidNotificationSettings(
notificationChannelName: 'Location tracking',
notificationTitle: 'Start Location Tracking',
notificationMsg: 'Track location in background',
notificationBigMsg:
'Background location is on to keep the app up-tp-date with your location. This is required for main features to work properly when the app is not running.',
notificationIconColor: Colors.grey,
notificationTapCallback:
LocationCallbackHandler.notificationCallback)));
}
This is the LocationRepositoryClass
class LocationServiceRepository {
static LocationServiceRepository _instance = LocationServiceRepository._();
LocationServiceRepository._();
factory LocationServiceRepository() {
return _instance;
}
static const String isolateName = 'LocatorIsolate';
int _count = -1;
Future<void> init(Map<dynamic, dynamic> params) async {
//TODO change logs
print("***********Init callback handler");
if (params.containsKey('countInit')) {
dynamic tmpCount = params['countInit'];
if (tmpCount is double) {
_count = tmpCount.toInt();
} else if (tmpCount is String) {
_count = int.parse(tmpCount);
} else if (tmpCount is int) {
_count = tmpCount;
} else {
_count = -2;
}
} else {
_count = 0;
}
print("$_count");
await setLogLabel("start");
final SendPort? send = IsolateNameServer.lookupPortByName(isolateName);
send?.send(null);
}
Future<void> dispose() async {
print("***********Dispose callback handler");
print("$_count");
await setLogLabel("end");
final SendPort? send = IsolateNameServer.lookupPortByName(isolateName);
send?.send(null);
}
#pragma('vm:entry-point')
Future<void> callback(LocationDto locationDto) async {
print('$_count location in dart: ${locationDto.toString()}');
await setLogPosition(_count, locationDto);
final SendPort? send = IsolateNameServer.lookupPortByName(isolateName);
send?.send(locationDto);//error here
_count++;
}
static Future<void> setLogLabel(String label) async {
final date = DateTime.now();
// await FileManager.writeToLogFile(
// '------------\n$label: ${formatDateLog(date)}\n------------\n');
}
static Future<void> setLogPosition(int count, LocationDto data) async {
final date = DateTime.now();
// await FileManager.writeToLogFile(
// '$count : ${formatDateLog(date)} --> ${formatLog(data)} --- isMocked: ${data.isMocked}\n');
}
static double dp(double val, int places) {
num mod = pow(10.0, places);
return ((val * mod).round().toDouble() / mod);
}
static String formatDateLog(DateTime date) {
return date.hour.toString() +
":" +
date.minute.toString() +
":" +
date.second.toString();
}
static String formatLog(LocationDto locationDto) {
return dp(locationDto.latitude, 4).toString() +
" " +
dp(locationDto.longitude, 4).toString();
}
}
and this is the locationCallbackHandler class
class LocationCallbackHandler {
static Future<void> initCallback(Map<dynamic, dynamic> params) async {
LocationServiceRepository myLocationCallbackRepository =
LocationServiceRepository();
await myLocationCallbackRepository.init(params);
}
static Future<void> disposeCallback() async {
LocationServiceRepository myLocationCallbackRepository =
LocationServiceRepository();
await myLocationCallbackRepository.dispose();
}
#pragma('vm:entry-point')
static void callback(LocationDto locationDto) async {
LocationServiceRepository myLocationCallbackRepository =
LocationServiceRepository();
await myLocationCallbackRepository.callback(locationDto);
}
static Future<void> notificationCallback() async {
print('***notificationCallback');
}
}
Everthing was working fine until this update with flutter and kotlin, Now i have the error
[ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: Invalid argument: is a regular instance: Instance of 'LocationDto'
E/flutter (26006): #0 _SendPort._sendInternal (dart:isolate-patch/isolate_patch.dart:249:43)
E/flutter (26006): #1 _SendPort.send (dart:isolate-patch/isolate_patch.dart:230:5)
E/flutter (26006): #2 LocationServiceRepository.callback
package:drivers_app/tabPages/location_service_reposirtory.dart:59
The error points to this code
#pragma('vm:entry-point')
Future<void> callback(LocationDto locationDto) async {
print('$_count location in dart: ${locationDto.toString()}');
await setLogPosition(_count, locationDto);
final SendPort? send = IsolateNameServer.lookupPortByName(isolateName);
send?.send(locationDto); //error here
_count++;
}
There is no reply from the plugin developer, Any help would be appreciated.

Answer 1

https://github.com/Yukams/background_locator_fixed/pull/53
There were some errors after updating flutter to version 3, If you run into this error then please visit the above website for the fix.