main, handle variable state values a bit better.

lib/main.dart

@@ -121,13 +121,19 @@ class _HomeScreenState extends State<HomeScreen> {
   Future<void> _loadPrefs() async {
     final prefs = await SharedPreferences.getInstance();
     setState(() {
-      _latController.text = prefs.getDouble('lat').toString();
+      final lat = prefs.getDouble('lat').toString();
-      _lngController.text = prefs.getDouble('lng').toString();
+      final lng = prefs.getDouble('lng').toString();
-      _sunsetController.text = prefs.getString('sunset_time').toString();
+      final sun = prefs.getString('sunset_time');
-      _alarmEnabled = prefs.getBool('alarm_enabled') ?? false;
+      final plu = prefs.getString('plural');
+      _latController.text = (lat == "null") ? "" : lat;
+      _lngController.text = (lng == "null") ? "" : lng;
+      _sunsetController.text = sun ?? "";
+      _plural = plu ?? "";
+
       _minutesBefore = prefs.getInt('minutes_before') ?? 30;
       _minutesController.text = _minutesBefore.toString();
-      _plural = prefs.getString('plural').toString();
+
+      _alarmEnabled = prefs.getBool('alarm_enabled') ?? false;
       _validTime = prefs.getBool('valid_time') ?? false;
     });
     if (_alarmEnabled && _sunsetController.text.isNotEmpty) {
@@ -208,7 +214,10 @@ class _HomeScreenState extends State<HomeScreen> {
     } catch (e) {
       _showSnack('Network Error: $e');
     } finally {
-      setState(() => _loading = false);
+      setState(() {
+        _loading = false;
+        _validTime = true;
+      });
     }
 
     if (_alarmEnabled) {
@@ -377,7 +386,9 @@ class _HomeScreenState extends State<HomeScreen> {
   }
 
   String? _validateTime(String? value) {
-    _validTime = false;
+    setState(() {
+      _validTime = false;
+    });
     if (value == null || !RegExp(r'^\d{2}:\d{2}$').hasMatch(value)) {
       return 'Use HH:MM Format';
     }
@@ -385,7 +396,9 @@ class _HomeScreenState extends State<HomeScreen> {
     final m = int.parse(value.substring(3, 5));
     if (h > 23) return 'Hour Must Be 0–23';
     if (m > 59) return 'Minute Must Be 0–59';
-    _validTime = true;
+    setState(() {
+      _validTime = true;
+    });
     return null; // valid
   }