Location manager optimizations

lib/managers/location_manager.class.dart

@@ -52,42 +52,66 @@ class LocationManager {
   }
 
   LocationManager._internal() {
-    startLocationService();
+    init();
   }
 
   final int defaultUpdateIntervalMinutes = 15;
   final int alarmId = 34901199;
+  Duration _updateInterval;
+  bool _isEnabled;
 
-  void startLocationService() async {
+  void init() async {
     SharedPreferences prefs = await SharedPreferences.getInstance();
     await prefs.reload();
-    bool enabled = prefs.getBool("location-enabled") ?? false;
+    _updateInterval = Duration(minutes: prefs.getInt("location-interval") ??
-    if (enabled) {
-      Duration locationUpdateInterval = Duration(
-          minutes: prefs.getInt("location-interval") ??
         defaultUpdateIntervalMinutes);
-      Logger.d("Scheduling location update for every ${locationUpdateInterval
+    _isEnabled = prefs.getBool("location-enabled") ?? false;
+    if (_isEnabled) {
+      _startLocationService();
+    }
+  }
+
+  void setSettings(bool enabled, int interval) async {
+    SharedPreferences prefs = await SharedPreferences.getInstance();
+    if (interval != _updateInterval.inMinutes) {
+      prefs.setInt("location-interval", interval);
+      _updateInterval = Duration(minutes: interval);
+    }
+    if (enabled && !_isEnabled) {
+      Logger.d("Enabling location service");
+      SharedPreferences prefs = await SharedPreferences.getInstance();
+      prefs.setBool("location-enabled", enabled);
+      _isEnabled = true;
+      _startLocationService();
+      updateDeviceLocation();
+    } else if (!enabled && _isEnabled) {
+      Logger.d("Disabling location service");
+      SharedPreferences prefs = await SharedPreferences.getInstance();
+      prefs.setBool("location-enabled", enabled);
+      _isEnabled = false;
+      _stopLocationService();
+    }
+  }
+
+  void _startLocationService() async {
+    Logger.d("Scheduling location update for every ${_updateInterval
         .inMinutes} minutes...");
     await AndroidAlarmManager.periodic(
-          locationUpdateInterval,
+        _updateInterval,
         alarmId,
         LocationManager.updateDeviceLocationIsolate,
         wakeup: true,
         rescheduleOnReboot: true
     );
-    } else {
+  }
-      Logger.d("Location tracking is disabled");
+
+  void _stopLocationService() async {
     Logger.d("Canceling previous schedule if any...");
     await AndroidAlarmManager.cancel(alarmId);
   }
-  }
 
   void updateDeviceLocation() async {
-    print("[Location] started");
+    if (_isEnabled) {
-    SharedPreferences prefs = await SharedPreferences.getInstance();
-    await prefs.reload();
-    bool enabled = prefs.getBool("location-enabled") ?? false;
-    if (enabled) {
       if (ConnectionManager().webhookId != null &&
           ConnectionManager().webhookId.isNotEmpty) {
         String url = "${ConnectionManager()

lib/managers/startup_user_messages_manager.class.dart

@@ -35,12 +35,7 @@ class StartupUserMessagesManager {
       positiveText: "Enable now",
       negativeText: "Cancel",
       onPositive: () {
-        SharedPreferences.getInstance().then((prefs) {
+        LocationManager().setSettings(true, 15);
-          prefs.setBool("location-enabled", true);
-          prefs.setBool(_locationTrackingMessageKey, true);
-          LocationManager().startLocationService();
-          LocationManager().updateDeviceLocation();
-        });
       },
       onNegative: () {
         SharedPreferences.getInstance().then((prefs) {

lib/panels/config_panel_widget.dart

@@ -11,7 +11,6 @@ class _ConfigPanelWidgetState extends State<ConfigPanelWidget> {
 
   int _locationInterval = LocationManager().defaultUpdateIntervalMinutes;
   bool _locationTrackingEnabled = false;
-  bool _needToRestartLocationTracking = false;
 
   @override
   void initState() {
@@ -31,24 +30,18 @@ class _ConfigPanelWidgetState extends State<ConfigPanelWidget> {
   }
 
   void incLocationInterval() {
-    _needToRestartLocationTracking = true;
     if (_locationInterval < 720) {
       setState(() {
         _locationInterval = _locationInterval + 1;
       });
-      SharedPreferences.getInstance().then((prefs) => prefs.setInt("location-interval", _locationInterval));
     }
   }
 
   void decLocationInterval() {
-    _needToRestartLocationTracking = true;
     if (_locationInterval > 1) {
       setState(() {
         _locationInterval = _locationInterval - 1;
       });
-      SharedPreferences.getInstance().then((prefs) {
-        prefs.setInt("location-interval", _locationInterval);
-      });
     }
   }
 
@@ -142,7 +135,6 @@ class _ConfigPanelWidgetState extends State<ConfigPanelWidget> {
                         SharedPreferences.getInstance().then((prefs) => prefs.setBool("location-enabled", value));
                         setState(() {
                           _locationTrackingEnabled = value;
-                          _needToRestartLocationTracking = true;
                         });
                       },
                     ),
@@ -191,13 +183,7 @@ class _ConfigPanelWidgetState extends State<ConfigPanelWidget> {
 
   @override
   void dispose() {
-    if (_needToRestartLocationTracking) {
+    LocationManager().setSettings(_locationTrackingEnabled, _locationInterval);
-      Logger.d("Location tracking settings was changed. Restarting location service...");
-      LocationManager().startLocationService();
-      if (_locationTrackingEnabled) {
-        LocationManager().updateDeviceLocation();
-      }
-    }
     super.dispose();
   }
 }