Update AndroidManifest to include foreground service permissions and implement tracking service in excursion screens. Refactor tracking logic to utilize TrackingService for better state management and streamline position updates.

android/app/src/main/AndroidManifest.xml

@@ -2,8 +2,8 @@
   <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
   <uses-permission android:name="android.permission.ACCESS_BACKGROUND_LOCATION" />
   <uses-permission android:name="android.permission.INTERNET"/>
-  <!-- <uses-permission android:name="android.permission.FOREGROUND_SERVICE" /> -->
-  <!-- <uses-permission android:name="android.permission.FOREGROUND_SERVICE_LOCATION" /> -->
+  <uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
+  <uses-permission android:name="android.permission.FOREGROUND_SERVICE_LOCATION" />
     <application
         android:label="LUPUS"
         android:name="${applicationName}"
@@ -37,11 +37,12 @@
             android:name="flutterEmbedding"
           android:value="2" />
 
-    <!-- <service -->
-    <!--     android:name="com.dexterous.flutterlocalnotifications.ForegroundService" -->
-    <!--     android:exported="false" -->
-    <!--     android:stopWithTask="false" -->
-    <!--     android:foregroundServiceType="<location>"> -->
+        <service
+            android:name=".TrackingService"
+            android:exported="false"
+            android:stopWithTask="false"
+            android:foregroundServiceType="location">
+        </service>
 
     </application>
     <!-- Required to query activities that can process text, see:

lib/screens/excursion/excursion_main.dart

@@ -19,6 +19,7 @@ import 'package:fforte/screens/sharedMethods/save_template.dart';
 import 'package:fforte/screens/sharedWidgets/datum.dart';
 import 'package:fforte/screens/sharedWidgets/var_text_field.dart';
 import 'package:fforte/l10n/app_localizations.dart';
+import 'package:fforte/services/tracking_service.dart';
 import 'package:flutter/material.dart';
 import 'package:geolocator/geolocator.dart';
 import 'package:shared_preferences/shared_preferences.dart';
@@ -147,7 +148,6 @@ class _ExcursionMainState extends State<ExcursionMain> {
       return currentPosition;
     });
 
-
     if (widget.existingData?.isNotEmpty ?? false) {
       for (var key in widget.existingData!.keys) {
         rmap[key]!["controller"]!.text =
@@ -188,268 +188,288 @@ class _ExcursionMainState extends State<ExcursionMain> {
   @override
   Widget build(BuildContext context) {
     List<Step> getSteps() => [
-      Step(
-        title: Text(AppLocalizations.of(context)!.dateandtime),
-        content: Column(
-          children: [
-            // ---------- Date
-            Datum(
-              initDatum: DateTime.now(),
-              onDateChanged: (date) {
-                rmap["Datum"]!["controller"]!.text = date.toString();
-              },
-              name: AppLocalizations.of(context)!.date,
-            ),
-            const SizedBox(height: 10),
-            // ---------- Pack
-            VarTextField(
-              textController: rmap["Rudel"]!["controller"]!,
-              localization: AppLocalizations.of(context)!.rudel,
-              dbName: "Rudel",
-              required: false,
-              dbDesignation: DatabasesEnum.excursion,
-            ),
-            const SizedBox(height: 10),
-            // ---------- Participants
-            VarTextField(
-              textController: rmap["Teilnehmer"]!["controller"]!,
-              localization: AppLocalizations.of(context)!.teilnehmer,
-              dbName: "Teilnehmer",
-              required: false,
-              dbDesignation: DatabasesEnum.excursion,
-            ),
-            const SizedBox(height: 10),
-            // ---------- Duration
-            VarTextField(
-              textController: rmap["Dauer"]!["controller"]!,
-              localization: AppLocalizations.of(context)!.dauer,
-              dbName: "Dauer",
-              required: false,
-              dbDesignation: DatabasesEnum.excursion,
-            ),
-            const SizedBox(height: 20),
-            // ---------- Dog(leash)
-            HundULeine(
-              mHund: rmap["MHund"]!["controller"]!,
-              mLeine: rmap["MLeine"]!["controller"]!,
-            ),
-            const SizedBox(height: 10),
-            // ---------- State
-            VarTextField(
-              textController: rmap["BLand"]!["controller"]!,
-              localization: AppLocalizations.of(context)!.bland,
-              dbName: "BLand",
-              required: false,
-              dbDesignation: DatabasesEnum.excursion,
-            ),
-            const SizedBox(height: 10),
-            // ---------- Country
-            VarTextField(
-              textController: rmap["Lkr"]!["controller"]!,
-              localization: AppLocalizations.of(context)!.lkr,
-              dbName: "Lkr",
-              required: false,
-              dbDesignation: DatabasesEnum.excursion,
-            ),
-            const SizedBox(height: 10),
-            // ---------- By State
-            VarTextField(
-              textController: rmap["BeiOrt"]!["controller"]!,
-              localization: AppLocalizations.of(context)!.beiort,
-              dbName: "BeiOrt",
-              required: false,
-              dbDesignation: DatabasesEnum.excursion,
-            ),
-            const SizedBox(height: 10),
-            // ---------- Bima number
-            const Divider(),
-            const SizedBox(height: 10),
-            ClipRRect(
-              borderRadius: BorderRadius.all(Radius.circular(10)),
-              child: ExpansionPanelList(
-                expansionCallback:
-                    ((int index, bool isExpanded) =>
+          Step(
+            title: Text(AppLocalizations.of(context)!.dateandtime),
+            content: Column(
+              children: [
+                // ---------- Date
+                Datum(
+                  initDatum: DateTime.now(),
+                  onDateChanged: (date) {
+                    rmap["Datum"]!["controller"]!.text = date.toString();
+                  },
+                  name: AppLocalizations.of(context)!.date,
+                ),
+                const SizedBox(height: 10),
+                // ---------- Pack
+                VarTextField(
+                  textController: rmap["Rudel"]!["controller"]!,
+                  localization: AppLocalizations.of(context)!.rudel,
+                  dbName: "Rudel",
+                  required: false,
+                  dbDesignation: DatabasesEnum.excursion,
+                ),
+                const SizedBox(height: 10),
+                // ---------- Participants
+                VarTextField(
+                  textController: rmap["Teilnehmer"]!["controller"]!,
+                  localization: AppLocalizations.of(context)!.teilnehmer,
+                  dbName: "Teilnehmer",
+                  required: false,
+                  dbDesignation: DatabasesEnum.excursion,
+                ),
+                const SizedBox(height: 10),
+                // ---------- Duration
+                VarTextField(
+                  textController: rmap["Dauer"]!["controller"]!,
+                  localization: AppLocalizations.of(context)!.dauer,
+                  dbName: "Dauer",
+                  required: false,
+                  dbDesignation: DatabasesEnum.excursion,
+                ),
+                const SizedBox(height: 20),
+                // ---------- Dog(leash)
+                HundULeine(
+                  mHund: rmap["MHund"]!["controller"]!,
+                  mLeine: rmap["MLeine"]!["controller"]!,
+                ),
+                const SizedBox(height: 10),
+                // ---------- State
+                VarTextField(
+                  textController: rmap["BLand"]!["controller"]!,
+                  localization: AppLocalizations.of(context)!.bland,
+                  dbName: "BLand",
+                  required: false,
+                  dbDesignation: DatabasesEnum.excursion,
+                ),
+                const SizedBox(height: 10),
+                // ---------- Country
+                VarTextField(
+                  textController: rmap["Lkr"]!["controller"]!,
+                  localization: AppLocalizations.of(context)!.lkr,
+                  dbName: "Lkr",
+                  required: false,
+                  dbDesignation: DatabasesEnum.excursion,
+                ),
+                const SizedBox(height: 10),
+                // ---------- By State
+                VarTextField(
+                  textController: rmap["BeiOrt"]!["controller"]!,
+                  localization: AppLocalizations.of(context)!.beiort,
+                  dbName: "BeiOrt",
+                  required: false,
+                  dbDesignation: DatabasesEnum.excursion,
+                ),
+                const SizedBox(height: 10),
+                // ---------- Bima number
+                const Divider(),
+                const SizedBox(height: 10),
+                ClipRRect(
+                  borderRadius: BorderRadius.all(Radius.circular(10)),
+                  child: ExpansionPanelList(
+                    expansionCallback: ((int index, bool isExpanded) =>
                         setState(() => bimaExtended = isExpanded)),
-                expandedHeaderPadding: EdgeInsets.all(0),
-                children: [
-                  ExpansionPanel(
-                    isExpanded: bimaExtended,
-                    canTapOnHeader: true,
-                    headerBuilder: (context, bool isOpen) => Padding(
-                      padding: const EdgeInsets.only(left: 15),
-                      child: Align(alignment: Alignment.centerLeft, child: Text("BImA", style: Theme.of(context).textTheme.bodyLarge,),),
-                    ),
-                    body: Padding(
-                      padding: const EdgeInsets.all(15),
-                      child: Column(
-                        children: [
-                          const SizedBox(height: 10),
-                          VarTextField(
-                            textController: rmap["BimaNr"]!["controller"]!,
-                            localization: AppLocalizations.of(context)!.bimaNr,
-                            dbName: "BimaNr",
-                            required: false,
-                            dbDesignation: DatabasesEnum.excursion,
+                    expandedHeaderPadding: EdgeInsets.all(0),
+                    children: [
+                      ExpansionPanel(
+                        isExpanded: bimaExtended,
+                        canTapOnHeader: true,
+                        headerBuilder: (context, bool isOpen) => Padding(
+                          padding: const EdgeInsets.only(left: 15),
+                          child: Align(
+                            alignment: Alignment.centerLeft,
+                            child: Text(
+                              "BImA",
+                              style: Theme.of(context).textTheme.bodyLarge,
+                            ),
                           ),
-                          const SizedBox(height: 10),
-                          // ---------- Bima name
-                          VarTextField(
-                            textController: rmap["BimaName"]!["controller"]!,
-                            localization: AppLocalizations.of(context)!.bimaName,
-                            dbName: "BimaName",
-                            required: false,
-                            dbDesignation: DatabasesEnum.excursion,
+                        ),
+                        body: Padding(
+                          padding: const EdgeInsets.all(15),
+                          child: Column(
+                            children: [
+                              const SizedBox(height: 10),
+                              VarTextField(
+                                textController: rmap["BimaNr"]!["controller"]!,
+                                localization:
+                                    AppLocalizations.of(context)!.bimaNr,
+                                dbName: "BimaNr",
+                                required: false,
+                                dbDesignation: DatabasesEnum.excursion,
+                              ),
+                              const SizedBox(height: 10),
+                              // ---------- Bima name
+                              VarTextField(
+                                textController:
+                                    rmap["BimaName"]!["controller"]!,
+                                localization:
+                                    AppLocalizations.of(context)!.bimaName,
+                                dbName: "BimaName",
+                                required: false,
+                                dbDesignation: DatabasesEnum.excursion,
+                              ),
+                              const SizedBox(height: 10),
+                              // ---------- Bima user
+                              BimaNutzer(
+                                onBimaNutzerChanged: (value) {
+                                  setState(() {
+                                    rmap["BimaNutzer"]!["controller"]!.text =
+                                        value;
+                                  });
+                                },
+                              ),
+                              const SizedBox(height: 10),
+                              // ---------- Bima AGV
+                              VarTextField(
+                                textController: rmap["BimaAGV"]!["controller"]!,
+                                localization:
+                                    AppLocalizations.of(context)!.bimaAGV,
+                                dbName: "BimaAGV",
+                                required: false,
+                                dbDesignation: DatabasesEnum.excursion,
+                              ),
+                            ],
                           ),
-                          const SizedBox(height: 10),
-                          // ---------- Bima user
-                          BimaNutzer(
-                            onBimaNutzerChanged: (value) {
-                              setState(() {
-                                rmap["BimaNutzer"]!["controller"]!.text = value;
-                              });
-                            },
-                          ),
-                          const SizedBox(height: 10),
-                          // ---------- Bima AGV
-                          VarTextField(
-                            textController: rmap["BimaAGV"]!["controller"]!,
-                            localization: AppLocalizations.of(context)!.bimaAGV,
-                            dbName: "BimaAGV",
-                            required: false,
-                            dbDesignation: DatabasesEnum.excursion,
-                          ),
-                        ],
+                        ),
                       ),
-                    ),
+                    ],
                   ),
-                ],
-              ),
+                ),
+              ],
             ),
-          ],
-        ),
-      ),
-      Step(
-        title: Text(AppLocalizations.of(context)!.umstaendeUndAktionen),
-        content: Column(
-          children: [
-            // ---------- Tracking
-            ElevatedButton(
-              onPressed:
-                  () => Navigator.push(
-                    context,
-                    MaterialPageRoute(
+          ),
+          Step(
+            title: Text(AppLocalizations.of(context)!.umstaendeUndAktionen),
+            content: Column(
+              children: [
+                // ---------- Tracking
+                ElevatedButton(
+                  onPressed: () async {
+                    await Navigator.push(context, MaterialPageRoute(
                       builder: (context) {
                         return Tracking(
                           weg: rmap["Weg"]!["controller"]!,
                           startPosition: currentPosition,
                         );
                       },
-                    ),
-                  ),
-              child: Text(AppLocalizations.of(context)!.trackingAnAusschalten),
-            ),
-            const SizedBox(height: 10),
+                    ));
+                    setState(() {});
+                  },
+                  child:
+                      Text(AppLocalizations.of(context)!.trackingAnAusschalten),
+                ),
+                const SizedBox(height: 10),
 
-            // ---------- Weather
-            VarTextField(
-              textController: rmap["Wetter"]!["controller"]!,
-              localization: AppLocalizations.of(context)!.wetter,
-              dbName: "Wetter",
-              required: false,
-              dbDesignation: DatabasesEnum.excursion,
+                // ---------- Weather
+                VarTextField(
+                  textController: rmap["Wetter"]!["controller"]!,
+                  localization: AppLocalizations.of(context)!.wetter,
+                  dbName: "Wetter",
+                  required: false,
+                  dbDesignation: DatabasesEnum.excursion,
+                ),
+                const SizedBox(height: 10),
+                // ---------- Temperature
+                VarTextField(
+                  textController: rmap["Temperat"]!["controller"]!,
+                  localization: AppLocalizations.of(context)!.temperatur,
+                  dbName: "Temperat",
+                  required: false,
+                  dbDesignation: DatabasesEnum.excursion,
+                ),
+                const SizedBox(height: 10),
+                // ---------- Last precipitation
+                LetzterNiederschlag(
+                    controller: rmap["RegenVor"]!["controller"]!),
+                const SizedBox(height: 20),
+                // ---------- Track conditions
+                StreckeUSpurbedingungen(
+                  kmAutoController: rmap["KmAuto"]!["controller"]!,
+                  kmFussController: rmap["KmFuss"]!["controller"]!,
+                  kmRadController: rmap["KmRad"]!["controller"]!,
+                  spGutController: rmap["SpGut"]!["controller"]!,
+                  spMittelController: rmap["SpMittel"]!["controller"]!,
+                  spSchlechtController: rmap["SpSchlecht"]!["controller"]!,
+                ),
+                const SizedBox(height: 20),
+                const Divider(),
+                // ---------- Track found
+                SpurGefunden(
+                  spurFund: rmap["SpurFund"]!["controller"]!,
+                  spurLang: rmap["SpurLang"]!["controller"]!,
+                  spurTiere: rmap["SpurTiere"]!["controller"]!,
+                  spSicher: rmap["SpSicher"]!["controller"]!,
+                  welpenSp: rmap["WelpenSp"]!["controller"]!,
+                  welpenAnz: rmap["WelpenAnz"]!["controller"]!,
+                  wpSicher: rmap["WpSicher"]!["controller"]!,
+                ),
+                const Divider(),
+                const SizedBox(height: 20),
+                // ---------- Counts
+                Anzahlen(
+                  losungAnz: rmap["LosungAnz"]!["controller"]!,
+                  losungGes: rmap["LosungGes"]!["controller"]!,
+                  losungGen: rmap["LosungGen"]!["controller"]!,
+                  urinAnz: rmap["UrinAnz"]!["controller"]!,
+                  urinGen: rmap["UrinGen"]!["controller"]!,
+                  oestrAnz: rmap["OestrAnz"]!["controller"]!,
+                  oestrGen: rmap["OestrGen"]!["controller"]!,
+                  haarAnz: rmap["HaarAnz"]!["controller"]!,
+                  haarGen: rmap["HaarGen"]!["controller"]!,
+                ),
+                const SizedBox(height: 20),
+                const Divider(),
+                const SizedBox(height: 20),
+                // ---------- Clues
+                Align(
+                  alignment: Alignment.bottomLeft,
+                  child: Text(
+                    AppLocalizations.of(context)!.hinweise,
+                    style: Theme.of(context).textTheme.titleMedium,
+                  ),
+                ),
+                Hinweise(hinweise: rmap["Hinweise"]!["controller"]!),
+              ],
             ),
-            const SizedBox(height: 10),
-            // ---------- Temperature
-            VarTextField(
-              textController: rmap["Temperat"]!["controller"]!,
-              localization: AppLocalizations.of(context)!.temperatur,
-              dbName: "Temperat",
-              required: false,
-              dbDesignation: DatabasesEnum.excursion,
+          ),
+          Step(
+            title: Text(AppLocalizations.of(context)!.intkomm),
+            content: Column(
+              children: [
+                // ---------- Remarks
+                VarTextField(
+                  textController: rmap["Bemerk"]!["controller"]!,
+                  localization: AppLocalizations.of(context)!.sonstbemerkungen,
+                  dbName: "Bemerk",
+                  required: false,
+                  dbDesignation: DatabasesEnum.excursion,
+                ),
+                const SizedBox(height: 20),
+                // ---------- Internal communication
+                VarTextField(
+                  textController: rmap["IntKomm"]!["controller"]!,
+                  localization: AppLocalizations.of(context)!.intkomm,
+                  dbName: "IntKomm",
+                  required: false,
+                  dbDesignation: DatabasesEnum.excursion,
+                ),
+              ],
             ),
-            const SizedBox(height: 10),
-            // ---------- Last precipitation
-            LetzterNiederschlag(controller: rmap["RegenVor"]!["controller"]!),
-            const SizedBox(height: 20),
-            // ---------- Track conditions
-            StreckeUSpurbedingungen(
-              kmAutoController: rmap["KmAuto"]!["controller"]!,
-              kmFussController: rmap["KmFuss"]!["controller"]!,
-              kmRadController: rmap["KmRad"]!["controller"]!,
-              spGutController: rmap["SpGut"]!["controller"]!,
-              spMittelController: rmap["SpMittel"]!["controller"]!,
-              spSchlechtController: rmap["SpSchlecht"]!["controller"]!,
-            ),
-            const SizedBox(height: 20),
-            const Divider(),
-            // ---------- Track found
-            SpurGefunden(
-              spurFund: rmap["SpurFund"]!["controller"]!,
-              spurLang: rmap["SpurLang"]!["controller"]!,
-              spurTiere: rmap["SpurTiere"]!["controller"]!,
-              spSicher: rmap["SpSicher"]!["controller"]!,
-              welpenSp: rmap["WelpenSp"]!["controller"]!,
-              welpenAnz: rmap["WelpenAnz"]!["controller"]!,
-              wpSicher: rmap["WpSicher"]!["controller"]!,
-            ),
-            const Divider(),
-            const SizedBox(height: 20),
-            // ---------- Counts
-            Anzahlen(
-              losungAnz: rmap["LosungAnz"]!["controller"]!,
-              losungGes: rmap["LosungGes"]!["controller"]!,
-              losungGen: rmap["LosungGen"]!["controller"]!,
-              urinAnz: rmap["UrinAnz"]!["controller"]!,
-              urinGen: rmap["UrinGen"]!["controller"]!,
-              oestrAnz: rmap["OestrAnz"]!["controller"]!,
-              oestrGen: rmap["OestrGen"]!["controller"]!,
-              haarAnz: rmap["HaarAnz"]!["controller"]!,
-              haarGen: rmap["HaarGen"]!["controller"]!,
-            ),
-            const SizedBox(height: 20),
-            const Divider(),
-            const SizedBox(height: 20),
-            // ---------- Clues
-            Align(
-              alignment: Alignment.bottomLeft,
-              child: Text(
-                AppLocalizations.of(context)!.hinweise,
-                style: Theme.of(context).textTheme.titleMedium,
-              ),
-            ),
-            Hinweise(hinweise: rmap["Hinweise"]!["controller"]!),
-          ],
-        ),
-      ),
-      Step(
-        title: Text(AppLocalizations.of(context)!.intkomm),
-        content: Column(
-          children: [
-            // ---------- Remarks
-            VarTextField(
-              textController: rmap["Bemerk"]!["controller"]!,
-              localization: AppLocalizations.of(context)!.sonstbemerkungen,
-              dbName: "Bemerk",
-              required: false,
-              dbDesignation: DatabasesEnum.excursion,
-            ),
-            const SizedBox(height: 20),
-            // ---------- Internal communication
-            VarTextField(
-              textController: rmap["IntKomm"]!["controller"]!,
-              localization: AppLocalizations.of(context)!.intkomm,
-              dbName: "IntKomm",
-              required: false,
-              dbDesignation: DatabasesEnum.excursion,
-            ),
-          ],
-        ),
-      ),
-    ];
+          ),
+        ];
 
     // Begin of widget tree
     return Scaffold(
-      appBar: AppBar(title: Text(AppLocalizations.of(context)!.excursion)),
+      appBar: AppBar(
+        title: Text(AppLocalizations.of(context)!.excursion),
+        actions: [
+          // Text(TrackingService().isTracking ? "Tracking" : "Not tracking")
+          Image.asset(
+            TrackingService().isTracking ? "assets/icons/tracking_on.png" : "assets/icons/tracking_off.png",
+            width: 40,
+            ),
+        ],
+      ),
       body: PageTransitionSwitcher(
         duration: const Duration(microseconds: 800),
         transitionBuilder: (

lib/screens/excursion/widgets/tracking.dart

@@ -1,11 +1,10 @@
 import 'dart:async';
-import 'dart:math';
 
 import 'package:fforte/l10n/app_localizations.dart';
 import 'package:fforte/screens/addCam/services/geolocator_service.dart';
 import 'package:fforte/screens/helper/add_entries_dialog_helper.dart';
 import 'package:fforte/screens/helper/snack_bar_helper.dart';
-import 'package:fforte/services/notification_service.dart';
+import 'package:fforte/services/tracking_service.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
 import 'package:flutter_map_location_marker/flutter_map_location_marker.dart';
@@ -22,20 +21,14 @@ class Tracking extends StatefulWidget {
 }
 
 class _TrackingState extends State<Tracking> {
-  List<LatLng> pathList = [];
-  StreamSubscription<Position>? positionStream;
+  final TrackingService _trackingService = TrackingService();
   LocationMarkerPosition? locationMarkerPosition;
-  bool positionStreamRunning = false;
   MapController mapController = MapController();
-
-  Random rand = Random();
+  StreamSubscription? _positionSubscription;
 
   @override
   void initState() {
-    // debugging (i guess)
-    // pathList.add(
-    //   LatLng(widget.startPosition.latitude, widget.startPosition.longitude),
-    // );
+    super.initState();
 
     if (widget.weg.text.isNotEmpty) {
       for (var element in widget.weg.text.split(";")) {
@@ -47,7 +40,7 @@ class _TrackingState extends State<Tracking> {
           // ignore because the double is short enough then
         }
 
-        pathList.add(
+        _trackingService.pathList.add(
           LatLng(double.parse(posSplit.first), double.parse(posSplit[1])),
         );
       }
@@ -59,7 +52,15 @@ class _TrackingState extends State<Tracking> {
       accuracy: widget.startPosition.accuracy,
     );
 
-    super.initState();
+    _positionSubscription = _trackingService.positionStream$.listen((position) {
+      setState(() {
+        locationMarkerPosition = LocationMarkerPosition(
+          latitude: position.latitude,
+          longitude: position.longitude,
+          accuracy: position.accuracy,
+        );
+      });
+    });
 
     GeolocatorService.alwaysPositionEnabled().then((value) {
       if (!value && mounted) {
@@ -71,101 +72,30 @@ class _TrackingState extends State<Tracking> {
 
   @override
   void dispose() {
-    if (positionStream != null) positionStream!.cancel();
-    bool isFirst = true;
-    if (pathList.isNotEmpty) {
-      for (var pos in pathList) {
-        if (!isFirst) {
-          widget.weg.text += ";";
-        } else {
-          isFirst = false;
-        }
-
-        widget.weg.text += "${pos.latitude},${pos.longitude}";
-      }
-    }
-    NotificationService().deleteNotification();
-
+    _positionSubscription?.cancel();
+    widget.weg.text = _trackingService.getPathAsString();
     super.dispose();
   }
 
-  final LocationSettings streamLocationSettings = LocationSettings(
-    accuracy: LocationAccuracy.high,
-    distanceFilter: 10,
-  );
-
-  void onTrackingStart() async {
-    // notification handling for tracking in background notification
-    await NotificationService().initNotification();
-
-    if (mounted) {
-      NotificationService().showNotification(
-        title: AppLocalizations.of(context)!.trackingRunningInBackground,
-      );
-    }
-
-    positionStream = Geolocator.getPositionStream(
-      locationSettings: AndroidSettings(
-        accuracy: LocationAccuracy.high,
-        distanceFilter: 0,
-        foregroundNotificationConfig:
-            mounted
-                ? ForegroundNotificationConfig(
-                  notificationTitle:
-                      AppLocalizations.of(context)!.trackingRunningInBackground,
-                  notificationText: "",
-                )
-                : null,
-
-      ),
-    ).listen((Position? position) {
-      if (position != null) {
-        setState(() {
-          pathList.add(LatLng(position.latitude, position.longitude));
-          // Random value for debugging
-          // pathList.add(LatLng(rand.nextInt(5) + 40, position.longitude));
-
-          locationMarkerPosition = LocationMarkerPosition(
-            latitude: position.latitude,
-            longitude: position.longitude,
-            accuracy: position.accuracy,
-          );
-        });
-      } else {
-        if (mounted) {
-          SnackBarHelper.showSnackBarMessage(
-            context,
-            AppLocalizations.of(context)!.couldntDeterminePosition,
-          );
-        }
-      }
-    });
-    positionStream!.onError((e) {
-      NotificationService().deleteNotification();
-      NotificationService().showNotification(title: "ERROR: $e");
-    });
-  }
-
   @override
   Widget build(BuildContext context) {
     return Scaffold(
       appBar: AppBar(
         title: Text(AppLocalizations.of(context)!.tracking),
-        leading: IconButton(onPressed: () {
-          Navigator.pop(context);
-        }, icon: Icon(Icons.arrow_back_rounded)),
+        leading: IconButton(
+          onPressed: () {
+            Navigator.pop(context);
+          },
+          icon: Icon(Icons.arrow_back_rounded)
+        ),
         actions: [
-          if (!positionStreamRunning)
+          if (!_trackingService.isTracking)
             IconButton(
               onPressed: () async {
-                bool delete =
-                    await AddEntriesDialogHelper.deleteCompleteRouteDialog(
-                      context,
-                    );
-
+                bool delete = await AddEntriesDialogHelper.deleteCompleteRouteDialog(context);
                 if (delete) {
                   setState(() {
-                    pathList = [];
+                    _trackingService.clearPath();
                   });
                 }
               },
@@ -174,32 +104,32 @@ class _TrackingState extends State<Tracking> {
                 color: Theme.of(context).colorScheme.errorContainer,
               ),
             ),
-          if (positionStreamRunning)
+          if (_trackingService.isTracking)
             TextButton(
               onPressed: () {
                 setState(() {
-                  positionStreamRunning = false;
-                  positionStream!.cancel();
-                  NotificationService().deleteNotification();
+                  _trackingService.stopTracking();
                 });
               },
               child: Text(AppLocalizations.of(context)!.trackingStop),
             ),
           TextButton(
             onPressed: () {
-              if (positionStreamRunning) {
-                positionStreamRunning = false;
-                positionStream?.pause();
-              } else {
-                positionStreamRunning = true;
-                onTrackingStart();
-              }
-              setState(() {});
+              setState(() {
+                if (_trackingService.isTracking) {
+                  _trackingService.pauseTracking();
+                } else {
+                  if (_trackingService.positionStream == null) {
+                    _trackingService.startTracking(context);
+                  } else {
+                    _trackingService.resumeTracking();
+                  }
+                }
+              });
             },
-            child:
-                positionStreamRunning
-                    ? Text(AppLocalizations.of(context)!.trackingPause)
-                    : Text(AppLocalizations.of(context)!.trackingStart)
+            child: _trackingService.isTracking
+                ? Text(AppLocalizations.of(context)!.trackingPause)
+                : Text(AppLocalizations.of(context)!.trackingStart),
           ),
         ],
       ),
@@ -219,8 +149,7 @@ class _TrackingState extends State<Tracking> {
         mapController: mapController,
         options: MapOptions(
           interactionOptions: const InteractionOptions(
-            flags:
-                InteractiveFlag.pinchZoom |
+            flags: InteractiveFlag.pinchZoom |
                 InteractiveFlag.drag |
                 InteractiveFlag.pinchMove,
           ),
@@ -235,22 +164,16 @@ class _TrackingState extends State<Tracking> {
             urlTemplate: 'https://tile.openstreetmap.org/{z}/{x}/{y}.png',
             userAgentPackageName: 'de.lupus.apps',
           ),
-          if (pathList.isNotEmpty)
+          if (_trackingService.pathList.isNotEmpty)
             PolylineLayer(
               polylines: [
-                Polyline(strokeWidth: 2.0, points: pathList, color: Colors.red),
+                Polyline(
+                  strokeWidth: 2.0,
+                  points: _trackingService.pathList,
+                  color: Colors.red
+                ),
               ],
             ),
-          // CircleLayer(
-          //   circles: [
-          //     CircleMarker(
-          //       color: Colors.blue,
-          //       point: pathList.isEmpty ? widget.startPosition : pathList.last,
-          //       radius: 5,
-          //       useRadiusInMeter: true,
-          //     ),
-          //   ],
-          // ),
           CurrentLocationLayer(),
         ],
       ),

lib/services/tracking_service.dart

@@ -0,0 +1,83 @@
+import 'dart:async';
+
+import 'package:fforte/l10n/app_localizations.dart';
+import 'package:fforte/services/notification_service.dart';
+import 'package:flutter/material.dart';
+import 'package:geolocator/geolocator.dart';
+import 'package:latlong2/latlong.dart';
+
+class TrackingService {
+  static final TrackingService _instance = TrackingService._internal();
+  factory TrackingService() => _instance;
+  TrackingService._internal();
+
+  List<LatLng> pathList = [];
+  StreamSubscription<Position>? positionStream;
+  bool isTracking = false;
+  final _positionController = StreamController<Position>.broadcast();
+
+  Stream<Position> get positionStream$ => _positionController.stream;
+
+  Future<void> startTracking(BuildContext context) async {
+    if (isTracking) return;
+
+    await NotificationService().initNotification();
+    if (context.mounted) {
+    NotificationService().showNotification(
+      title: AppLocalizations.of(context)!.trackingRunningInBackground,
+    );
+    }
+
+    positionStream = Geolocator.getPositionStream(
+      locationSettings: AndroidSettings(
+        accuracy: LocationAccuracy.high,
+        distanceFilter: 0,
+        foregroundNotificationConfig: ForegroundNotificationConfig(
+          notificationTitle: context.mounted ? AppLocalizations.of(context)!.trackingRunningInBackground : "Tracking",
+          notificationText: "",
+        ),
+      ),
+    ).listen((Position? position) {
+      if (position != null) {
+        pathList.add(LatLng(position.latitude, position.longitude));
+        _positionController.add(position);
+      }
+    });
+
+    positionStream!.onError((e) {
+      NotificationService().deleteNotification();
+      NotificationService().showNotification(title: "ERROR: $e");
+    });
+
+    isTracking = true;
+  }
+
+  void pauseTracking() {
+    positionStream?.pause();
+    isTracking = false;
+  }
+
+  void resumeTracking() {
+    positionStream?.resume();
+    isTracking = true;
+  }
+
+  void stopTracking() {
+    positionStream?.cancel();
+    NotificationService().deleteNotification();
+    isTracking = false;
+  }
+
+  void clearPath() {
+    pathList.clear();
+  }
+
+  String getPathAsString() {
+    return pathList.map((pos) => "${pos.latitude},${pos.longitude}").join(";");
+  }
+
+  void dispose() {
+    stopTracking();
+    _positionController.close();
+  }
+}