Fix: Passt das Verhalten der InputFelder an, dass sich diese wirklich verändern

lib/Pages/Misc/InputFields/date_range_picker.dart

@@ -1,5 +1,6 @@
 import 'package:flutter/material.dart';
 
+import '../../../Services/date_service.dart';
 import '../../Dialog/dialog_action.dart';
 import '../../Dialog/dialog_input_field.dart';
 import '../../Dialog/dialog_input_field_type_enum.dart';
@@ -9,16 +10,13 @@ import '../../Dialog/dynamic_dialog.dart';
 class DateRangePicker extends StatefulWidget {
   /// Initialisiert eine neue Instanz dieser Klasse
   const DateRangePicker({
+    this.controller,
     this.autofocus = false,
     super.key,
     this.decoration,
-    this.initialValue,
     this.onChanged,
   });
 
-  /// Der Initiale Wert des Input-Feldes
-  final DateTimeRange? initialValue;
-
   /// Ob das Feld automatisch ausgewählt werden soll
   final bool autofocus;
 
@@ -28,42 +26,39 @@ class DateRangePicker extends StatefulWidget {
   /// Die Dekoration, wie das Feld aussehen soll
   final InputDecoration? decoration;
 
+  /// Der Controller über den der Wert des Inputfeldes gesetzt
+  /// und ausgelesen werden kann
+  final TextEditingController? controller;
+
   @override
   State<StatefulWidget> createState() => _DateRangePicker();
 }
 
 class _DateRangePicker extends State<DateRangePicker> {
-  final ValueNotifier<DateTimeRange?> _value = ValueNotifier(null);
+  final TextEditingController _valueController = TextEditingController();
 
   @override
-  void initState() {
-    super.initState();
+  void dispose() {
+    _valueController.dispose();
 
-    _value.value = widget.initialValue;
-    _value.addListener(() {
-      widget.onChanged?.call(_value.value);
-    });
+    super.dispose();
   }
 
   @override
   Widget build(final BuildContext context) => TextField(
     readOnly: true,
-    controller: TextEditingController(
-      text: widget.initialValue != null
-          ? '${widget.initialValue!.start.day}'
-                '.${widget.initialValue!.start.month}'
-                '.${widget.initialValue!.start.year}'
-                ' - '
-                '${widget.initialValue!.end.day}'
-                '.${widget.initialValue!.end.month}'
-                '.${widget.initialValue!.end.year}'
-          : null,
-    ),
+    controller: widget.controller ?? _valueController,
     decoration: widget.decoration,
     onTap: _pickDateRange,
   );
 
   Future<void> _pickDateRange() async {
+    final TextEditingController controller =
+        widget.controller ?? _valueController;
+
+    final DateTimeRange<DateTime>? dateTimeRange =
+        DateService.stringToDateTimeRange(controller.text);
+
     await DynamicDialog(
       title: 'Zeitraum auswählen',
       inputFields: [
@@ -72,14 +67,14 @@ class _DateRangePicker extends State<DateRangePicker> {
           label: 'Startdatum',
           keyboardType: TextInputType.datetime,
           inputType: DialogInputFieldTypeEnum.date,
-          initialValue: _value.value?.start,
+          initialValue: dateTimeRange?.start,
         ),
         DialogInputField(
           id: 'dateTo',
           label: 'Enddatum',
           keyboardType: TextInputType.datetime,
           inputType: DialogInputFieldTypeEnum.date,
-          initialValue: _value.value?.end,
+          initialValue: dateTimeRange?.end,
         ),
       ],
       actions: [
@@ -87,7 +82,8 @@ class _DateRangePicker extends State<DateRangePicker> {
         DialogAction(
           label: 'Leeren',
           onPressed: (_) {
-            _value.value = null;
+            controller.text = '';
+            widget.onChanged?.call(null);
           },
         ),
         DialogAction(
@@ -98,10 +94,13 @@ class _DateRangePicker extends State<DateRangePicker> {
                 values['dateFrom'] is DateTime &&
                 values['dateTo'] != null &&
                 values['dateTo'] is DateTime) {
-              _value.value = DateTimeRange(
+              final DateTimeRange<DateTime> timeRange = DateTimeRange(
                 start: values['dateFrom'],
                 end: values['dateTo'],
               );
+
+              controller.text = DateService.dateTimeRangeToString(timeRange)!;
+              widget.onChanged?.call(timeRange);
             }
           },
         ),

lib/Pages/Misc/InputFields/dynamic_date_time_field.dart

@@ -1,6 +1,7 @@
 import 'package:date_field/date_field.dart';
 import 'package:flutter/material.dart';
-import 'package:intl/intl.dart';
+
+import '../../../Services/date_service.dart';
 
 /// Ein Feld mit Popup über welches man Datumsfelder auswählen kann
 class DynamicDateTimeField extends StatefulWidget {
@@ -45,7 +46,7 @@ class _DynamicDateTimeFieldState extends State<DynamicDateTimeField> {
   @override
   Widget build(final BuildContext context) => DateTimeField(
     initialPickerDateTime: widget.initialValue,
-    dateFormat: DateFormat('d.M.y'),
+    dateFormat: DateService.dateFormat,
     value: _value,
     mode: widget.mode,
     autofocus: widget.autofocus,