Added initial ask for gradesystem in gradeaverage

lib/storage/base/settingsProvider.dart

@@ -27,6 +27,8 @@ class SettingsProvider extends ChangeNotifier {
   void reset() async {
     _storage = await SharedPreferences.getInstance();
     _storage.remove(_fieldName);
+    _settings = DefaultSettings.get();
+    await update();
 
     notifyListeners();
   }
@@ -51,7 +53,7 @@ class SettingsProvider extends ChangeNotifier {
     notifyListeners();
   }
 
-  void update() async {
+  Future<void> update() async {
     await _storage.setString(_fieldName, jsonEncode(_settings.toJson()));
   }
 

lib/storage/gradeAverages/gradeAveragesSettings.dart

@@ -6,9 +6,10 @@ part 'gradeAveragesSettings.g.dart';
 @JsonSerializable()
 class GradeAveragesSettings {
   bool useGradeSystem;
+  bool askedForPreferredGradeSystem;
   List<int> inputs;
 
-  GradeAveragesSettings({required this.useGradeSystem, required this.inputs});
+  GradeAveragesSettings({required this.useGradeSystem, required this.askedForPreferredGradeSystem, required this.inputs});
 
   factory GradeAveragesSettings.fromJson(Map<String, dynamic> json) => _$GradeAveragesSettingsFromJson(json);
   Map<String, dynamic> toJson() => _$GradeAveragesSettingsToJson(this);

lib/storage/gradeAverages/gradeAveragesSettings.g.dart

@@ -10,6 +10,8 @@ GradeAveragesSettings _$GradeAveragesSettingsFromJson(
         Map<String, dynamic> json) =>
     GradeAveragesSettings(
       useGradeSystem: json['useGradeSystem'] as bool,
+      askedForPreferredGradeSystem:
+          json['askedForPreferredGradeSystem'] as bool,
       inputs: (json['inputs'] as List<dynamic>).map((e) => e as int).toList(),
     );
 
@@ -17,5 +19,6 @@ Map<String, dynamic> _$GradeAveragesSettingsToJson(
         GradeAveragesSettings instance) =>
     <String, dynamic>{
       'useGradeSystem': instance.useGradeSystem,
+      'askedForPreferredGradeSystem': instance.askedForPreferredGradeSystem,
       'inputs': instance.inputs,
     };

lib/view/pages/more/gradeAverages/gradeAverage.dart

@@ -30,12 +30,45 @@ class _GradeAverageState extends State<GradeAverage> {
     }
   }
 
+  void switchSystem(bool e) => setState(() {
+    grades.clear();
+    gradeSystem = e;
+    settings.val(write: true).gradeAveragesSettings.useGradeSystem = e;
+    _persistGrades();
+  });
+
   @override
   void initState() {
     super.initState();
     
     grades = settings.val().gradeAveragesSettings.inputs;
     gradeSystem = settings.val().gradeAveragesSettings.useGradeSystem;
+
+    WidgetsBinding.instance.addPostFrameCallback((timeStamp) {
+      if(!settings.val().gradeAveragesSettings.askedForPreferredGradeSystem) {
+        settings.val(write: true).gradeAveragesSettings.askedForPreferredGradeSystem = true;
+        showDialog(context: context, builder: (context) => AlertDialog(
+          title: const Text("Notensystem"),
+          content: const Text("Wähle dein bevorzugtes Schulnotensystem"),
+          actions: [
+            TextButton(
+              onPressed: () {
+                switchSystem(true);
+                Navigator.of(context).pop();
+              },
+              child: const Text("Realschule"),
+            ),
+            TextButton(
+              onPressed: () {
+                switchSystem(false);
+                Navigator.of(context).pop();
+              },
+              child: const Text("Oberstufe"),
+            ),
+          ],
+        ));
+      }
+    });
   }
 
   @override
@@ -82,12 +115,6 @@ class _GradeAverageState extends State<GradeAverage> {
             )).toList(),
 
             onSelected: (e) {
-              void switchSystem() => setState(() {
-                grades.clear();
-                gradeSystem = e;
-                settings.val(write: true).gradeAveragesSettings.useGradeSystem = e;
-                _persistGrades();
-              });
 
               if(grades.isNotEmpty) {
                 showDialog(
@@ -96,11 +123,11 @@ class _GradeAverageState extends State<GradeAverage> {
                     title: "Notensystem wechseln",
                     content: "Beim wechsel des Notensystems werden alle Einträge zurückgesetzt.",
                     confirmButton: "Fortfahren",
-                    onConfirm: () => switchSystem(),
+                    onConfirm: () => switchSystem(e),
                   ),
                 );
               } else {
-                switchSystem();
+                switchSystem(e);
               }
             },
           ),

lib/view/settings/defaultSettings.dart

@@ -19,6 +19,7 @@ class DefaultSettings {
       devToolsEnabled: false,
       gradeAveragesSettings: GradeAveragesSettings(
           useGradeSystem: true,
+          askedForPreferredGradeSystem: false,
           inputs: []
       ),
       timetableSettings: TimetableSettings(