added comments and refactored code

lib/pages/landing_page.dart

@@ -17,7 +17,7 @@ class LandingPage extends StatefulWidget {
 
 // uses mixin OverlayService to show loading overlay
 class _LandingPageState extends State<LandingPage> with OverlayService {
-  late FloodStationProvider floodStationProvider;
+  late FloodStationProvider _floodStationProvider;
 
   @override
   void dispose() {
@@ -27,7 +27,7 @@ class _LandingPageState extends State<LandingPage> with OverlayService {
 
   @override
   Widget build(BuildContext context) {
-    floodStationProvider = context.watch<FloodStationProvider>();
+    _floodStationProvider = context.watch<FloodStationProvider>();
     return Column(
       children: [
         StationFilter(
@@ -54,9 +54,9 @@ class _LandingPageState extends State<LandingPage> with OverlayService {
 
     return Expanded(
       child: FloodStationListView(
-        stations: floodStationProvider.filtered
-            ? floodStationProvider.filteredStations
-            : floodStationProvider.allStations,
+        stations: _floodStationProvider.filtered
+            ? _floodStationProvider.filteredStations
+            : _floodStationProvider.allStations,
         onItemTapped: _navigateToStationDetail,
       ),
     );
@@ -64,7 +64,7 @@ class _LandingPageState extends State<LandingPage> with OverlayService {
 
   void _handleFilterChange(String filterText) {
     if (filterText.isEmpty) {
-      floodStationProvider.filtered = false;
+      _floodStationProvider.filtered = false;
       setState(() {});
       return;
     }
@@ -73,14 +73,14 @@ class _LandingPageState extends State<LandingPage> with OverlayService {
       context: context,
       message: 'Loading',
       onDismiss: () {
-        floodStationProvider.cancelFilterLoading();
+        _floodStationProvider.cancelFilterLoading();
       },
     );
 
-    floodStationProvider.loadFilteredStations(filterText);
-    floodStationProvider.filteredStationsFuture
+    _floodStationProvider.loadFilteredStations(filterText);
+    _floodStationProvider.filteredStationsFuture
         ?.then((_) => removeLoadingNotifier());
-    floodStationProvider.filtered = true;
+    _floodStationProvider.filtered = true;
   }
 
   void _handleLoadAllStations() {
@@ -88,27 +88,27 @@ class _LandingPageState extends State<LandingPage> with OverlayService {
       context: context,
       message: 'Loading',
       onDismiss: () {
-        floodStationProvider.cancelFilterLoading();
+        _floodStationProvider.cancelFilterLoading();
       },
     );
 
-    floodStationProvider
+    _floodStationProvider
         .loadAllStations()
         .whenComplete(() => removeLoadingNotifier());
   }
 
   void _navigateToStationDetail(FloodStation station) {
-    floodStationProvider.selectedStation = station;
+    _floodStationProvider.selectedStation = station;
     Navigator.of(context).pushNamed(FloodStationPage.routeName);
   }
 
   // returns boolean to decide whether the list of stations should be shown
   // if the list of stations is empty and is not filtered either, the function returns false
   bool get _shouldShowList {
-    if (!floodStationProvider.filtered &&
-        floodStationProvider.allStations.isNotEmpty) {
+    if (!_floodStationProvider.filtered &&
+        _floodStationProvider.allStations.isNotEmpty) {
       return true;
     }
-    return floodStationProvider.filtered;
+    return _floodStationProvider.filtered;
   }
 }